Change search
Refine search result
1234567 101 - 150 of 337
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 101.
    Ek, Josefin
    Jönköping University, School of Education and Communication.
    Tvådimensionella och tredimensionella figurer som undervisningsinnehåll i geometriundervisning på lågstadiet: En jämförelseanalys av hur lärare organiserar och genomför geometriundervisning i årskurs 1-3 i relation till van Hiele ́s teori2018Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The subject area for this study in mathematics, specified geometry. The purpose of the study is to investigate how teachers describe how they work with the mathematical field of geometry to enable and develop students' geometric skills. The underline theory is socio-cultural perspective, since social interaction can result in geometric concept understanding. The study was conducted through interviews with five teachers with varied long professional experience. Analysis of material was done through qualitative content analysis and teacher reasoning against each other in order to distinguish similarities and differences in the organization of teaching and working methods. Teachers' reasoning is also made in relation to Van Hiele's theory, in order to distinguish similarities and differences of empirical and theory. The result showed that geometry education is a recurring area at the lower stage and therefore should not take too much time. Teaching is based on teaching materials and its structure is monitored throughout the work area. Implementation of teaching is preferred to do in smaller student groups and concrete materials and digital tools are included as support for pupils' knowledge development regarding two- dimensional and three-dimensional figures'. Previous content is discussed in relation to Van Hiele's theory, socio-cultural perspective and curriculum.

  • 102.
    Ekdahl, Anna-Lena
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Differences in pre-school teachers' ways of handling a part-part-whole activity2018Conference paper (Refereed)
    Abstract [en]

    The data in this paper draws from an eight-month intervention study based on the idea that children need to discern the first ten natural numbers as relations of parts and whole to develop their arithmetic skills. In order to implement educational activities according to this conjecture, a group of Swedish preschool teachers worked closely with a research team, planning, enacting and analyzing activities. In this paper I describe how nine pre-school teachers, across 67 video-recorded films, handled one of these activities, called the ‘snake game’ with their groups of 5-year-old children. Using analysis based on variation theory, the results point to differences in the enactment of the ‘snakegame’ in terms of if and how the teachers foregrounded the structural aspects of numbers embedded in the activity.

  • 103.
    Ekdahl, Anna-Lena
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Different learning possibilities from the same activity - Swedish preschool teachers’ enactment of a number relation activityManuscript (preprint) (Other academic)
  • 104.
    Ekdahl, Anna-Lena
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Teaching for the learning of additive part-whole relations: The power of variation and connections2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, results from four empirical studies and a re-analysis are synthesized with what can constitute a structural approach to teaching and learning additive part-whole relations among learners aged four to eight years. In line with a structural approach to additive relations, the relations of parts and whole are in focus from the outset and are seen as the basis for addition and subtraction (Davydov 1982; Neuman, 1987). This approach was introduced by the researches in two intervention studies across different contexts. The researches collaborated with teachers in planning part-whole activities, teachers teaching them in their own settings, and then reflecting on them together with the research team. The empirical material consists of video-recorded lessons (Grade 3), small-group teaching (preschool) and individual video-recorded task-based learner interviews (with preschoolers). The teaching episodes and interviews were analyzed on a micro-level, using analytical tools and concepts from variation theory (Marton, 2015). To deepen the knowledge, a re-analysis was also conducted with the purpose of identifying qualitative differences in teachers’ enactments of mathematical ideas and principles associated with a structural approach to additive relations.

    Looking at the articles and the re-analysis, the results suggest that, for learning, it matters which representations are offered to the children. Some representations seem to facilitate the discernment of the parts and whole, and their relations. The results suggest that it matters which examples are offered. A systematic sequence of examples has the potential to bring to the fore relations between different part-whole examples, which offer the children opportunity to learn mathematical principles such as commutativity. Furthermore, the results indicate that what is made possible to learn about additive part-whole relations is associated with what aspects are opened up as dimensions of variation (Marton, 2015). Foremost, though, the results reveal the importance of making connections to highlight number relations and key features associated with the structural approach to additive relations. The results suggest that how variation is offered, and whether and how the teacher explicitly (verbally and gesturally) draws attention to relations, ideas and aspects, is crucial for the learning of additive part-whole relations. Moreover, through the separate articles and the re-analysis, the outcomes indicate that the structural approach to additive part-whole relations and conjectures from variation theory are possible to implement in different contexts and for different ages of children.

  • 105.
    Ekdahl, Anna-Lena
    et al.
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Björklund, Camilla
    Göteborgs universitet.
    ”10-masken” och förskolebarns lärande i målstyrda processer2018Conference paper (Other (popular science, discussion, etc.))
    Abstract [sv]

    I forskningsprojektet FASETT (VR-UVK 2014-1791) undersöker vi 5-åringars taluppfattning och aritmetikfärdigheter och möjligheterna att genom målorienterade processer stötta barn i att utveckla framgångsrika strategier för aritmetisk problemlösning. I två kommuner har vi tillsammans med förskollärare prövat ut aktiviteter i syfte att utveckla särskilda förmågor som förmodas vara nödvändiga för framgångsrik problemlösning i aritmetik, såsom att urskilja tals del-helhets-struktur, fingertal samt representationer av tal. Barnens (N= 65) taluppfattning och hur deras förskollärare arbetat med förmågorna på ett systematiskt sätt presenteras i föreläsningen, med tyngdpunkt på vad som görs möjligt att lära i aktiviteterna och effekter för barnens utveckling av talförståelse och aritmetikfärdigheter. Aktiviteter som prövats ut i projektet är teoretiskt grundade i Variationsteorin (Marton, 2015). I projektet uppmuntrar vi användning av fingrarna som redskap för att strukturera tal och operera med tal. Flera av aktiviteterna påminner om bekanta lekar och spel från förskolan, till exempel tärningsspel, ”10-masken” och enklare räknesagor. I föreläsningen presenterar vi en fördjupad analys av aktiviteten ”10-masken”, hur förskollärarna iscensatt aktiviteten på olika sätt och vilken betydelse det har haft för barnens lärandemöjligheter. ”10-masken” består av ett snöre med tio pärlor, där ett antal pärlor göms i handen och resten förblir synliga. Uppgiften är att ta reda på hur många pärlor som är gömda. Detta är inte en ny aktivitet i förskolan. Däremot, indikerar vår analys, spelar det roll hur en aktivitet med så många matematiska idéer introduceras och tas om hand av förskolläraren i mötet med barnen. Baserat på resultatet kan vi se att ”10-masken” erbjuder en potential av viktiga matematiska idéer, som är av stor pedagogisk betydelse för barns matematiklärande, men det spelar en avgörande roll hur förskolläraren gör i aktiviteten.

  • 106.
    Ekdahl, Anna-Lena
    et al.
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research. Wits School of Education, University of the Witwatersrand, Johannesburg, South Africa.
    Björklund, Camilla
    University of Gothenburg, Sweden.
    Runesson Kempe, Ulla
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research. Wits School of Education, University of the Witwatersrand, Johannesburg, South Africa.
    Teaching to change ways of experiencing numbers – An intervention program for arithmetic learning in preschool2019In: Proceedings of the 43rd Annual Meeting of the International Group for the Psychology of Mathematics Education: Volume 2: Research Reports (A-K) / [ed] Mellony Graven, Hamsa Venkat, Anthony A. Essien & Pamela Vale, Pretoria, South Africa: PME , 2019, p. 209-216Conference paper (Refereed)
    Abstract [en]

    This paper reports on an eight months long intervention program with eight five-year-olds in Swedish preschool. Four main activities were designed to enable the children to discern part-part-whole relations of the first ten numbers. The aim of this paper is to present how progress in children’s arithmetical skills are associated with the activities they have encountered in the intervention program. Learning outcomes based on pre-, post- and delayed interviews show that the participating children made distinct progress in the way they experience numbers, with long-term effects on their arithmetic skills. In this paper we discuss the analysis of what was taught and what was learnt incommensurable terms.

  • 107.
    Ekdahl, Anna-Lena
    et al.
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Kullberg, Angelika
    University of Gothenburg, Sweden.
    Different learning possibilities in preschool mathematics from the same task2018Conference paper (Refereed)
    Abstract [en]

    In this paper one specific task in a series of tasks focusing on part-part-whole relations of the ten first natural numbers and finger patterns for structure number relations, is presented and discussed. The tasks were designed, planned and enacted in an intervention program conducted in Swedish preschool during an eight-month period. In the program nine preschool teachers worked in close collaboration with the research team in planning how to enact tasks with their 5-year-old children, in an iterative process. The specific task, called the ‘snake game’, consists of five or ten beads on a string, some of the beads where to be hidden and the children would find out the hidden part by using structured finger patterns. The task was designed in accordance with the variation theory assumptions that certain aspects need to be discerned as dimensions of variations. The aim of the paper is to examine which dimensions of variations that were opened up by the teachers and what was made possible for the children to learn from the enactment of the ‘snake game task’. The data set includes 67 video observations from the teacher’s enactment of the task. The results suggest that what seems to be a ‘non-complex task’ (five/ ten beads on a string) offers rich mathematical experiences and has potential to bring fore important aspects of numbers and number relations. However, depending on which dimensions of variations that were opened up reveals different learning possibilities.

  • 108.
    Ekdahl, Anna-Lena
    et al.
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Lundberg, Birgitta
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Keerekes, Klara
    Matematik i förskoleklassen VA-MER: Ett samverkansprojekt mellan Vaggeryds kommun och Mathematics Education Research2019Conference paper (Other academic)
    Abstract [sv]

    De senaste åren har en rad förändringar gällande förskoleklassen genomförts. Den 1 juli 2016 fick förskoleklassen en egen del i läroplanen och från och med läsåret 2018/19 blev förskoleklassen obligatorisk och omfattas nu av skolplikten. Det förändrade uppdraget i förskoleklassen samt det obligatoriska kartläggningsmaterialet, har ökat lärares behov av att möta uppdraget. Kartläggningsmaterialet i matematiskt tänkande ska hjälpa lärare att tidigt identifiera elever som visar en indikation på att inte nå de kunskapskrav som sen ska uppnås i årskurs 3 i grundskolan. Däremot saknas direkta implikationer för undervisning som stimulerar alla elevers möjlighet att utveckla sina förmågor i matematik.

    I ett nystartat samverkansprojekt mellan Vaggeryds kommun och Högskolan för Lärande och Kommunikation kommer kommunens alla lärare i förskoleklass att arbeta tillsammans med forskare tillhörande forskargruppen i matematik (MER-gruppen), i syfte att stärka likvärdighet i utbildningen inom Vaggeryd kommun.

    Syftet med projektet är att se hur en pedagogisk verksamhet i samverkan med forskare kan bidra till att lärarna:

    • utvecklar förmågan att diskutera ämnesinnehåll i matematikundervisningen,
    • utvecklar förmågan att utifrån kartläggningsmaterialet diskutera didaktiska implikationerna för undervisning,
    • gemensamt bygger ett fundament i matematikundervisningen, med stöd av aktuell forskning, i syfte att utveckla alla elevers förmågor i matematik.

    Erfarenheter från ett nyligen avslutat forskningsprojekt där lärare och forskare i tätt samarbete genomförde och reflekterade över undervisningsaktiviteter, visar att detta verkade vara en framgångsrik modell för att utveckla undervisning. Därför väljs ett liknande upplägg i detta samverkansprojekt.

    I den inledande fasen av projektet träffas lärargruppen och forskarna en gång per månad. Träffarna förläggs på kommunens skolor. De påbörjade samtalen mellan deltagarna i samverkansprojektet visar att det finns ett stort behov av att diskutera matematikundervisning och att utveckla ett målinriktat arbete som främjar alla elevers möjligheter att lära matematik.

  • 109.
    Englund Eriksson, Cathrine
    Jönköping University, School of Education and Communication.
    Associativitet: Grundskoleelever urskiljer den associativa lagen2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The fundamental properties of arithmetic is a central aspect for students´ understanding of algebra. Therefore, it is important that students get the opportunity to discern and understand these properties. In this qualitative study based on interviews I examine how 16 students in grades 2-5, reason, make generalizations and use the associative property of addition when working on a pre-designed sequence of instructions. The study shows that many students do discern the associative property of addition when working on the sequence of instructions, but only a few of them apply this property when calculating. The study also shows that several of the students are making generalizations about the associative property by relating it to addition or subtraction. The conclusion of the study is that a sequence of instructions that offers systematic variation and a reccurance of expressions based on the same structures, makes it possible for students to discern and describe associativity. The discernment is also made possible by prompting the students to view the expressions from different perspectives and describing the expressions in terms of similarities and differences.

  • 110.
    Engström, Klara
    Jönköping University, School of Education and Communication.
    Språket möjliggör elevers lärande: En studie om språkutvecklande arbete i matematik2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The gap between the underperforming and the high performing Swedish pupils in mathematics is growing and the differences appear mainly between the pupils with different language and social backgrounds (Skolverket, 2016). Pupils’ linguistic skills are considered most important in the Swedish school system (Skolverket, 2018) and therefore are all teachers obliged to work with language development in their subjects. The purpose with the study is to contribute with knowledge of how working with the development of language in mathematics is enabled in grade 3 and 6. Mathematics teachers for pupils in grade 3 and 6 were interviewed to fulfill that purpose. The study is based on the socio-cultural theory where the focus is on that the teacher together with the pupils creates an education where the language develops in social interaction. The result of the study reveals that mathematics teachers in grade 3 and 6 are working with development of language in mathematics and utilize methods such as individual support, mathematical texts, textbook, and challenging assignments for individuals. It was  revealed how teachers view  their task to develop pupils’ language and there are multiple factors that affect the quality of teaching. The conclusion of the study shows that the language development in mathematics is enabled through the teachers who believe they have an important role if they have the opportunities that are necessary and use favorable ways to work with.

  • 111. Engström, Klara
    et al.
    Krusell, Natalie
    Språk + matematik = sant?: En litteraturöversikt om språk- och kunskapsutvecklande arbetssätt i matematikundervisningen2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Dagens skola blir mer och mer mångkulturell. Det ställer krav på lärare och undervisning att möta alla elevers språk- och kunskapsnivåer i alla ämnen, inklusive matematikämnet. Syftet med studien är att uppmärksamma språkets betydelse i matematikundervisningen genom att beskriva olika arbetssätt där språket främjas i undervisningen. Den nationella och internationella forskningen som granskats i den här litteraturöversikten framhåller vikten av ett språk- och kunskapsutvecklande arbetssätt i matematikundervisningen. Artiklar har sökts från olika söktjänster och genomgått ett urval med bestämda kriterier. Ett språk- och kunskapsutvecklande arbetssätt i matematiken präglas av många tillfällen till interaktion och elevdelaktighet. Viktigt är också de olika sätt lärare kan använda för att på olika sätt stötta elever samt deras planering för kognitivt utmanade uppgifter, vilket framgår av studiens resultat. Även att arbeta med matematiska texter, begrepp och understryka språkets betydelse och syfte i undervisningen visar sig vara gynnsamt för elevers lärande och utveckling. Vidare diskuteras även studiens relevans för lärare i matematikämnet samt huruvida ett språk- och kunskapsutvecklande arbetssätt ställs i kontrast till styrdokumenten.

  • 112. Engsund, Maja
    Individualisering i matematikklassrummet: En kvalitativ studie om lärares syn på individualisering i matematikundervisningen2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 113. Faag, Julia
    Helt programmerad: På vilka sätt kan programmering uppfattas av lärare?2018Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 114.
    Faag, Julia
    et al.
    Jönköping University, School of Education and Communication, HLK, School Based Research, Mathematics Education Research.
    Faag, Louise
    Jönköping University, School of Education and Communication, HLK, School Based Research, Mathematics Education Research.
    Programmering som matematisk lärandemiljö: Kan programmering bidra till att utveckla matematiska förmågor?2017Student paper other, 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Finns det matematik i programmering? Den svenska regeringen och Skolverket verkar ha den uppfattningen. Det finns dock åsikter som pekar på motsatsen.

    På grund av samhällets ökade digitalisering gav regeringen Skolverket i uppdrag att ta fram ett förslag på Nationella it- strategier för skolväsendet (2016). Förslaget godtogs av regeringen den 9 mars 2017. Avsikten med förslaget är att utveckla elevers digitala kompetens genom att bland annat införa programmering i läroplanen, främst i kursplanen för matematik. Den vetenskapliga grunden för förslaget har däremot ifrågasatts. Denna litteraturstudie syftar därför till att undersöka förhållandet mellan programmering och matematik gällande vilka förmågor som kan utvecklas. De förmågor som programmering i forskning beskrivs kunna utveckla, jämförs med de fem förmågorna i kursplanen för matematik. Studiens slutsats är att forskning visar att programmering kan utveckla flera förmågor som kan anses vara matematiska, exempelvis problemlösningsförmåga, kreativ förmåga och samarbetsförmåga.

  • 115. Faag, Louise
    Programmering genom de lärandes ögon: Hur uppfattar elever matematiska aspekter av programmering?2018Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 116.
    Flarup, Andrea
    Jönköping University, School of Education and Communication, HLK, School Based Research, Mathematics Education Research.
    Hur elever i årskurs 1 förstår likhetstecknet2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study aims to analyze the understanding of the equal sign among students in first grade and to identify critical aspects in their descriptions of the equal sign. Data were collected from a classroom observation.  Also interviews with five students from the observed class were made.  The students were interviewed about their understanding of the equal sign and about their perceptions of mathematical tasks with focus on the equal sign.  There are elements in the study of Phenomenography and Variation Theory. The results of the study show that students have both relational and instrumental understanding of the equal sign. The result also show that different students have identified different critical aspects of the equal sign during their descriptions. The conclusion is that students’ ability to identify a critical aspect depends on the structure of the task.

  • 117.
    Flarup, Andrea
    et al.
    Jönköping University, School of Education and Communication, HLK, School Based Research, Mathematics Education Research.
    Abramsson, Matilda
    Jönköping University, School of Education and Communication, HLK, School Based Research, Mathematics Education Research.
    Ett plus ett blir två: Introduktion av likhetstecknet i förskoleklass och årskurs 12015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 118.
    Fredriksson, Pär
    Jönköping University, School of Education and Communication.
    Varför mönster?: En kvalitativ studie om matematiklärares uppfattningar2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Matematik är uppbyggt av olika områden som alla hänger samman. Ett av de viktigaste områdena är algebra som ofta inleds med mönster och talföljder. Algebra har varit, och är fortfarande, svenska elevers svagaste område visar resultat från internationella jämförelser. Det som påverkar elevers kunskaper är till stor del undervisningen i skolan. Undervisning påverkas av lärare som i sin tur påverkas av läroplanen. Studiens syfte är att ta reda på hur matematiklärare tolkar det som står i läroplanen om mönster, vad de ser för syfte själva med att undervisa om mönster och vad området innebär för dem. Eftersom svenska läroplanen till skillnad från andra länders läroplaner inte är så detaljstyrande kan innehållet uppfattas på olika sätt. För att undersöka lärares uppfattningar har studien inspirerats av fenomenografi. I resultatet presenteras nio olika kategorier som ämnar besvara studiens tre forskningsfrågor: ”Hur beskriver lärare mönster inom matematik?”, ”Vad uppfattar lärare för syfte med att undervisa om mönster?” och ”Hur tolkar lärare innehållet om mönster i läroplanen?”. Kategorierna är presenterade efter skillnader och likheter. Resultatet visar bland annat att lärare tolkar läroplanen som otydlig och att förståelsen för mönster kan vara en medfödd talang. Det har även framkommit att lärare ser flera syften med att undervisa om mönster. Det uppfattas vara positivt för både algebra, problemlösning och logiskt tänkande. I diskussionen vägs resultatet mot tidigare forskning och ett resonemang om styrdokument och läromedel förs. Avslutningsvis ges förslag på vidare forskning.

  • 119.
    Fredriksson, Pär
    et al.
    Jönköping University.
    Hyltén, Ola
    Jönköping University.
    Elever och den explicita formeln: En litteraturöversikt om elevers lärande relaterad till växande geometriska mönster och explicit formel.2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Matematik är ett ämne som elever över hela världen behöver lära sig. I de senare årskurserna bygger ämnet på att elever ska kunna behärska algebra. Vi har valt att fokusera på mönster vilket många anser vara inkörsporten till algebra. För att lärare ska kunna erbjuda elever en rättvis utbildning bör de ha kunskap om elevers svårigheter och lärande. Vår litteraturstudie har riktat in sig på att försöka svara på vad forskning säger om elevers lärande till växande geometriska mönster och explicit formel. I de elva studier som valts ut har vi kommit fram till att några gemensamma slutsatser finns men även sådana som skiljer sig åt. Att elever behöver utveckla sitt språk och få förståelse för innebörden av bokstavssymboler i matematiken är en viktig slutsats för lärande relaterad till mönster. Studierna har dessutom visat en stark relevans i att samordna olika delar till en helhet. Svenska elevers resultat i internationella undersökningar problematiseras och vad som kan tänkas vara orsaken till att de presterar sämre i mönsterrelaterade uppgifter än vad de gör i övriga delar i matematiken. Vårt resultat är till stor del överensstämmande med hur de svenska styrdokumenten förhåller sig till ämnet. Trots det har svenska elever svårigheter med att uttrycka en explicit formel till ett växande geometriskt mönster. Just den explicita formeln är viktig för elevers helhetsförståelse av mönster och tidig algebra.

  • 120.
    Friggeråker, Erik
    et al.
    Jönköping University, School of Education and Communication.
    Wallin, Emil
    Jönköping University, School of Education and Communication.
    IKT i matematikundervisningen: En litteraturstudie om användningen av IKT i matematikundervisning i grundskolan2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Digitaliseringen av skolan är i ständig utveckling och därför är det viktigt att lärare vet hur de använder sig av digital teknik i sin undervisning. EU har beslutat att digital kompetens är en av åtta nyckelkompetenser för ett livslångt lärande. Det innebär att tekniken kan användas på fritiden och i arbetslivet. Syftet med studien är att i matematikdidaktisk forskning undersöka hur IKT påverkar undervisning inom matematik i grundskolan. Syftet besvaras genom frågorna: Möjligheter och hinder med IKT i matematikundervisning, möjligheter och hinder för elevers lärande genom användandet av IKT samt vilka faktorer som påverkar användandet av IKT i skolan.  

    Litteraturen samlades in via sökningar i databaser. Resultaten som framgick var av stor del internationell och skriven på engelska. Vid analys av det material som samlats in användes en översiktsmatris samt innehållskriterier för att avgöra texternas relevans till studien. Resultatet visade att IKT kan vara både ett hinder eller en möjlighet inom matematikundervisning. Faktorer som påverkade var bland annat en välplanerad undervisning, den digitala infrastrukturen samt elevers motivation till lärande genom IKT. IKT i matematikundervisning är något som kräver fortsatt utveckling. Många lärare anser att det inte är lika kompatibelt med IKT i matematikundervisning jämfört med IKT inom språkämnen.  

  • 121.
    Gegerfelt, Gideon
    et al.
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Johansson, Alexander
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Surfplattor - ett kompletterande verktyg i matematikundervisningen: En litteraturstudie om surfplattors användning i matematikundervisningen för att utveckla elevers kunskaper i aritmetik2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 122. Gegerfelt, Stina
    Digitala läromedel i matematik: En intervjustudie om lärares uppfattningar om digitala läromedel i matematik2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The digitalization of Swedish schools has developed over the recent years and the use of digital educational materials is more common today. The aim of this study is therefore to increase our understanding of teachers’ conceptions about digital educational materials in mathematics. This will be done by means of four questions: which opportunities and difficulties do teachers perceive with the use of digital educational materials in mathematics? How do teachers perceive pupils’ learning when they work with digital educational materials in mathematics and how do teachers perceive the difference, if there is one, between analogue and digital educational materials in mathematics?

     

    The study is based on conceptions and they are in focus. When collecting different conceptions semi-structured interviews were used and five teachers have been interviewed to find out their conceptions about digital educational materials. The material has been transcribed and analyzed, in order to present a correct result. The result shows that teachers’ conceptions of digital educational material can be divided into two categories; that digital educational materials are a complement to analogue educational materials and that digital educational materials are equivalent analogue educational materials. Opportunities that teachers see with digital educational materials are that they provide quick feedback and they motivate pupils. Difficulties that teachers perceive are that certain parts are more difficult to do digital and there might be bugs in the digital educational materials.

  • 123.
    Gol Mohammadi, Nazanin
    et al.
    Jönköping University, School of Education and Communication, HLK, School Based Research, Mathematics Education Research.
    Zhang, Ying
    Jönköping University, School of Education and Communication, HLK, School Based Research, Mathematics Education Research.
    Matematik på svenska och kinesiska: en komparativ studie mellan svenska och kinesiska läroböcker inom området andragradsekvationer2011Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med den här studien är att 1) jämföra upplägget av läromedel i Sverige och i Kina (Shanghai), 2) jämföra de lösningsmetoder som presenteras i läromedlen samt 3) undersöka hur läromedlen präglats av den matematiska kulturen i respektive land. Vår studie bygger på APOS-teorin (kompletterat med PCK), en teori som bland annat beskriver processen av matematikinlärning i olika steg. Studien har vidare gått till så att vi gjort en textanalys och studerat de valda läromedlen, Matematik år 8 (Liu, 2006) för Kina och Exponent B Röd (Gennow m.fl., 2004) för Sverige, för att hitta såväl likheter som skillnader mellan läromedlen. Resultatet av studien sammanfattas till att läromedlen till största delen tar upp samma metoder inom det studerade området. Den upptäckta skillnaden ligger i de övningsuppgifter som presenterats. Exponent B Röd (Gennow m.fl., 2004) innehåller betydligt fler övningsuppgifter som dessutom i många fall har en tillämpande karaktär, medan uppgifterna i Matematik år 8 (Liu, 2006) innehåller färre uppgifter, som oftast är abstrakta och aritmetiska. Detta har vi tolkat som ett resultat av den rådande kulturen i respektive land. Den kinesiska skolan har en starkare betoning på prov och har därför läroboken som en förberedelse inför kommande provtillfällen. Den svenska skolan däremot använder termer som förståelse och lustfyllt lärande, vilket medför att även läroboken försöker spegla detta genom vardagsnära kopplingar, främst i form av övningsuppgifter.

  • 124.
    Gradin, Lovisa
    et al.
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Lennartsson, Emilia
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Eye-tracking och elevers lärande i matematik: En litteraturstudie2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med den här studien är att sammanställa och problematisera forskning kring hur eye-tracking som metod kan användas för att synliggöra elevers förståelse för matematik. Eye-tracking är en metod där människors ögonrörelser studeras för att undersöka den visuella uppmärksamheten utifrån fixeringar och sackader. En eye-tracker är en apparat som används för att mäta ögonrörelser.  Studiernas undersökningar utgår från en hypotes om att det finns ett samband mellan ögonrörelser och kognitiva processer. Sammanställningen har sitt ursprung i en litteraturstudie där artiklar har funnits genom sökningar i olika databaser. Tolv vetenskapliga studier valdes ut baserat på inklusions- och exklusionskriterier, och analyserades i detalj. Dessa studier pekar på att eye-tracking kan visa skillnader mellan vilka strategier eleverna använder, skillnader mellan hög- och lågpresterande elever samt skillnader i kognitiv belastning. Studierna visar också att det finns flera möjligheter med eye-tracking som metod men lyfter också fram begränsningar. En möjlighet är att eye-tracking i vissa fall är mer objektiv än andra metoder och en annan är att eye-tracking kan visa strategier som eleven själv inte kan verbalisera. Begränsningar är att den kognitiva uppmärksamheten inte alltid stämmer överens med deltagarens visuella fokus samt att resultatet kan vara svårt att urskilja vid emotionella reaktioner.  Eye-tracking jämförs ofta med olika sorters intervjuer och flera studier förespråkar att kombinera eye-tracking med andra metoder för att samla in kompletterande data. I slutet av texten lyfts de etiska dilemman fram som kan uppstå vid eye-tracking.

  • 125.
    Grieder, Jessica
    Jönköping University, School of Education and Communication.
    Hitta en väg till programmering: Hur kan programmering utgöra en del av matematikundervisningen?2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since autumn 2018, programming is a part of the algebra content in the Swedish curriculum. Due to an insecurity many teachers feel towards mathematic teaching about programming, there is a need to know what such teaching can look like. This design research study creates an understanding of how mathematical programming lessons can be designed to develop students spatial reasoning and understanding of how distinct step-by- step instructions can be created and improved. Design research builds on developing interventions (lessons), and testing and adjusting them in a systematic way.

    Important aspects for being able to learn how to program are spatial reasoning and an understanding of instructions. This design research focuses on the development of design principles that will lead to an understanding of the important aspects of learning how to program and the construction of rewarding teaching activities. The activities are unplugged, meaning that there are no digital tools involved.

    The most important finding of this study is the importance of four design principles; variation of the objects starting point; mixing of instructions; testing and 2D/3D as well as two teaching activities and a worksheet that seem to lead to a development of spatial reasoning and an understanding of instructions.

  • 126.
    Grieder, Jessica
    Jönköping University, School of Education and Communication.
    Programmering i skolan: Kan undervisning med hjälp av programmering bidra till att utveckla problemlösningsförmågan?2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Kan undervisning med hjälp av programmering utveckla den matematiska problemlösningsförmågan? Olika studier besvarar den frågan med ja. För ett mer noggrant svar på den här frågan har olika studier analyserats för att kartlägga sambandet mellan programmering och problemlösning.

    Genom en litteraturstudie, där information systematiskt har samlats in från olika forskningsprojekt och sedan jämförts, har det lyfts fram vilka olika förmågor, med speciellt fokus på problemlösningsförmågan, som kan utvecklas genom undervisning i programmering samt hur denna undervisning bör se ut. Förmågorna har sedan jämförts med de olika faser som vi genomgår när vi löser problem. Vidare diskuteras om förmågorna, som elever kan utveckla genom undervisning med hjälp av programmering, även kan överföras till problem i andra kontexter.

    Slutsatsen från studien är att problemlösningsförmågan verkar kunna utvecklas genom undervisning med hjälp av programmering, framförallt om den kompletteras med problemlösningsinstruktioner.

  • 127.
    Gundstedt, Mikael
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Svensson, Rikard
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Analys av Itabs lösfot och stolpe2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    What is the most important aspect when shelves are being sold, manufactured and used? Well they must be user-friendly which means they should be easy to assemble, carry and modify. They should also be easy to ship, weight aspect and not ungainly. Most importantly it must be worth its price or just cheap, to accomplish this one should keep the amount of material to a minimum whilst the manufacturing must be easy.

    These were some of the questions at issue that this work has started from and they have more or less thoroughly been penetrated.

    In an effort to acquire some answers the possibility to reduce the thickness of the poles to the shelves from 2,5 mm to 2,0 mm, this would present partial solutions to both weight and material issues but before all the price issue though the material contributes to a large piece of the cost. This suggestion appeared when the poles were investigated and calculated from different angels to determine if they would hold out to this kind of change. The angels that were investigated are bending of the pole, the holes in the pole will be sheared (ripped like can opener-effect) by the hooks on the shelf consol and the detachable foot. The result that emerged are that some sizes of the poles can endure the change without any thought whilst the smaller poles requires some further testing and pondering before implementing. The aspect that was found to be norm setting was the bending of the pole.

    The fact that the user friendliness always can be improved a helper was designed. The helper is meant for the user is so he/she easily can see how much merchandise (weight) a shelf and pole can withstand. In other words to make sure that the shelf/pole is not overloaded and risk a breakdown.

    To declare where Itabs system is in regards to its competitor on these important questions a competitor analysis was conducted. The primary test-issues were stability, easy to assemble and if there are any apparent hazardous areas on the stand. Unfortunately there were some difficulties in retrieving the stands from some of the competitors or more importantly the stand from Itab themselves. So a comparison was not possible although they who were interested in testing their stands and had sent them in were to be pleased so a test was conducted. The issue regarding the price was not compared though this report is not meant for the users in the stores.

  • 128.
    Gunnarsdotter, Ylva
    Jönköping University, School of Education and Communication, HLK, School Based Research, Other School Based Research.
    Appar i matematikundervisningen: En intervjustudie om lärares användning av appar i matematikundervisningen2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Tablets and apps are more and more often used in math teaching. An app is a software program used for tablet computers.

    The purpose of this study is to create knowledge about how teachers in classes 1–3 teach math with help of different apps. The study was made through qualitative interviews with six teachers who work continuously with applications in math teaching. The result shows that if apps are to be used in teaching there should be a clear goal and purpose of the use. It should also be possible to relate to the curriculum and the course book. Furthermore, the study reveals that there are different ways and purposes of using apps. The apps are mainly described as complementary tools and as an asset in order to introduce a mathematical area. The teachers’ purposes were, for example, to increase the amount of practice, individualization, or to create a higher accomplishment rate. Other purposes of using apps were to produce direct feedback, increase student motivation, or for evaluation and follow-up. The selections of apps which were used for teaching varied and were chosen in three different ways; through free choice, via an ICT responsible, or via an IT office.

  • 129.
    Gunnarsson, Robert
    et al.
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Albinsson, Malin
    Järfälla barn- och elevhälsa, Järfälla kommun, och Department of Special Education, Stockholm University.
    A phenomenographic analysis of students’ use of base-ten material2020Conference paper (Refereed)
    Abstract [en]

    Previous research indicates that manipulatives, like base-ten blocks, not necessarily strengthen students’ understanding of numerical place-value and the decimal numeral system. This study takes its starting point in the hypothesis that to create functional teaching situations with base-ten blocks, it is necessary to first know students’ prior understanding of such manipulatives. Therefore, here we present a phenomenographic analysis of students’ understanding how such manipulative material can be used to represent multidigit numbers. The data was collected from individual interviews with 58 students in grade 1 (6-7 years old).We identify six qualitatively different categories of students’ understanding, and, based on these, suggest implications for the design of teaching situations.

  • 130.
    Gunnarsson, Robert
    et al.
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Papadopoulos, I.
    Pairing numbers: An unconventional way of evaluating arithmetic expressions2019Conference paper (Refereed)
  • 131.
    Gunnarsson, Robert
    et al.
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Papadopoulos, Ioannis
    Aristotle University, Thessaloniki, Greece.
    The impact of number pairing on students' ideas on how to evaluate numerical expressions2018In: Proceedings of the 42nd Conference of the International Group for the Psychology of Mathematics Education: Vol. 5 / [ed] E. Bergqvist, M. Österholm, C. Granberg & L. Sumpter, Umeå: PME , 2018, p. 238-238Conference paper (Refereed)
  • 132.
    Gunnarsson, Robert
    et al.
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Runesson, Ulla
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research.
    Håkansson, Per
    Jönköping University, School of Education and Communication, HLK, Praktiknära utbildningsforskning (PUF), Mathematics Education Research. Vasaskolan, Skövde.
    Identifying what is critical for learning ‘rate if change’: Experiences from a learning study in Sweden2019In: Theory and practice of lesson study in mathematics: An international perspective / [ed] R. Huang, A. Takahashi & J. P. da Ponte, Cham: Springer, 2019, p. 441-456Chapter in book (Refereed)
    Abstract [en]

    Learning study is an adapted version of lesson study developed in Hong Kong and Sweden. It has commonalities with lesson study but is framed within a specific pedagogical learning theory – variation theory. Central in variation theory is the object of learning and what is critical for students’ learning. Hence, as with lesson study, it is a collective and iterative work where teachers explore how they can make the object of learning available to students, but what characterises learning study is the use of a specific learning theory. In this process, special attention is paid to the critical aspects of the object of learning. We argue that to identify the aspects that are critical, the aspects need to be verified and refined in classrooms. In this chapter, we demonstrate how teachers gain knowledge about such critical aspects. Particularly, we show how these critical aspects cannot be extracted only from the mathematical content or the students pre-understanding alone, but evolve during the learning study cycles. For this we use a learning study about the mathematical topic of rate of change in grade 9 in Sweden as an illustration. We describe how an analysis of how students solved tasks in pre- and post-test and during the lessons, as well as how the mathematical content was presented in lessons, helped the teachers identify what was critical for learning to understand and express the rate of change for a dynamic situation.

  • 133.
    Habimana, Olivier
    Jönköping University, Jönköping International Business School, JIBS, Economics. Department of Applied Statistics, College of Business and Economics, University of Rwanda, Kigali, Rwanda.
    Asymmetric nonlinear mean reversion in real effective exchange rates: A Fisher-type panel unit root test applied to Sub-Saharan Africa2016In: Journal of Economic Asymmetries, ISSN 1703-4949, Vol. 14, p. 189-198Article in journal (Refereed)
    Abstract [en]

    This study investigates the nonlinear data generating processes of real effective exchange rates in a panel of Sub-Saharan African countries; the region with the highest transportation costs, trade barriers in international arbitrage and frequent central bank intervention in the foreign exchange market, which are plausible main sources of nonlinear and asymmetric deviations from purchasing power parity. By means of Monte Carlo simulations, we use the empirical distributions of the exponential smooth transition autoregressive (ESTAR), and the asymmetric ESTAR data generating processes to test for mean reversion in monthly real effective exchange rates. We then apply Fisher's inverse chi-square test that combines the observed significance levels of independent univariate unit root tests to test for panel unit roots. The findings suggest that once nonlinearities and asymmetries are taken into account, there is more evidence in favor of the purchasing power parity hypothesis. 

  • 134.
    Habimana, Olivier
    Jönköping University, Jönköping International Business School, JIBS, Economics. Department of Applied Statistics, College of Business and Economics, University of Rwanda, Kigali, Rwanda.
    Asymmetric Nonlinear Mean Reversion in Real Effective Exchange Rates: Evidence from Sub-Saharan AfricaManuscript (preprint) (Other academic)
    Abstract [en]

    This paper evaluates the purchasing power parity (PPP) theory in a panel of Sub-Saharan African (SSA) countries. The study applies unit root tests that are based on exponential smooth transition autoregressive (ESTAR) models to account for nonlinearities and asymmetries in real exchange rate adjustment towards its equilibrium (mean) value. Nonlinearities and asymmetries are very relevant for these countries and are potentially due to transaction costs, trade barriers and other market frictions, and frequent official interventions in the foreign exchange market. Results indicate that once nonlinearities and asymmetries are taken into account there is more empirical support for the PPP theory in SSA.

  • 135.
    Habimana, Olivier
    Jönköping University, Jönköping International Business School, JIBS, Economics.
    Asymmetry and multiscale dynamics in macroeconomic time series analysis2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis consists of three independent articles preceded by an introductory chapter. The first two articles focus on exchange rate dynamics in emerging market and developing economies, taking into account nonlinearities and asymmetries which are relevant for these countries and are potentially due to (i) transaction costs and other market frictions, and (ii) official intervention in the foreign exchange market. The third article is devoted to the analysis of the effects of monetary policy at different time horizons.

    The first article evaluates the purchasing power parity (PPP) theory in a panel of Sub-Saharan African countries. Unit root tests that are based on exponential smooth transition autoregressive (ESTAR) models are applied to account for nonlinearities and asymmetries in real exchange rate adjustment towards its equilibrium (mean) value. The results indicate empirical support for the PPP theory.

    The second article examines the relationship between current account adjustment and exchange rate flexibility in a panel of emerging market and developing economies. The purpose of this article is to (i) obtain a measure of exchange rate flexibility that considers autoregressive conditional heteroscedasticity and possible asymmetric responses of the exchange rate to shocks, and (ii) apply suitable dynamic panel data estimators to investigate this relationship. The results indicate that more flexible exchange rates are associated with faster current account adjustment.

    By means of wavelets the third article investigates the liquidity effect and the long-run neutrality of money at detailed timescales using time series data for Sweden and the US. The results indicate a significant liquidity effect at horizons of one to four years, but there is no evidence of monetary neutrality.

  • 136.
    Habimana, Olivier
    Jönköping University, Jönköping International Business School, JIBS, Economics. Department of Applied Statistics, College of Business and Economics, University of Rwanda, Kigali, Rwanda.
    Do flexible exchange rates facilitate external adjustment? A dynamic approach with time-varying and asymmetric volatilityManuscript (preprint) (Other academic)
    Abstract [en]

    This paper revisits the claim that flexible exchange rates facilitate external adjustments, in a panel of emerging market and developing economies. In contrast to previous studies which mainly use the exchange rate regime classification as a proxy for exchange rate flexibility, the present study estimates a measure of exchange rate flexibility that considers autoregressive conditional heteroskedasticity (ARCH) effects and possible asymmetric responses of the exchange rate to shocks. Generalized method of moments (GMM) estimators are employed to estimate the dynamic relationship between exchange rate flexibility and the speed of current account adjustment. The results suggest that more flexible exchange rates are associated with faster adjustment of current account imbalances, and when the possibility of an asymmetric response of exchange rate to shocks is taken into account, the estimated speed of adjustment is even higher.

  • 137.
    Habimana, Olivier
    Jönköping University, Jönköping International Business School, JIBS, Economics. Department of Applied Statistics, College of Business and Economics, University of Rwanda, Kigali, Rwanda.
    Wavelet multiresolution analysis of the liquidity effect and monetary neutralityManuscript (preprint) (Other academic)
    Abstract [en]

    This paper employs wavelets to examine the relationship between money, interest and output on a scale-by-scale basis using data for the US and Sweden during 1985-2017. First, series are decomposed into orthogonal timescale components using the discrete wavelet transform (DWT) together with the Daubechies least asymmetric wavelet filter, and then causality analysis (in the Granger sense) is performed at each scale of variations. The dynamics at the finest scale of one-year movements indicate that interest rate and real output respond to movements in the quantity of money. At horizons of four years and above, there is a feedback mechanism. This pattern is very similar in both countries at the mentioned scales and suggests that monetary disturbances have significant real effects and these effects last longer than is assumed in pure real-business cycle models. Further, a locally weighted regression analysis suggests that not only are the direction and strength of the relationship among these variables scale-dependent but also the shape of the relationship may change from one scale to another. This method suggests a negative relationship between money and the short-term interest rate, as predicted by the liquidity preference theory, at cycles of one to four-year periods. Overall, these findings highlight the relevance of timescale decomposition in macroeconomic analysis.

  • 138.
    Habimana, Olivier
    Jönköping University, Jönköping International Business School, JIBS, Economics. Department of Applied Statistics, College of Business and Economics, University of Rwanda, Kigali, Rwanda.
    Wavelet multiresolution analysis of the liquidity effect and monetary neutrality2019In: Computational Economics, ISSN 0927-7099, E-ISSN 1572-9974, Vol. 53, no 1, p. 85-110Article in journal (Refereed)
    Abstract [en]

    This paper employs the maximum overlap discrete wavelet transform to obtain timescale decompositions of monetary aggregates, short-term interest rates and output to investigate two propositions in monetary economics: the liquidity effect and the long-run neutrality of money. Evidence from correlation and Granger causality over five timescales suggests that the liquidity effect is statistically significant in both the US and Sweden’s economies, with a shorter time horizon in the US than in Sweden. There is no evidence of monetary neutrality in both economies; at finest timescales, output Granger causes money in Sweden, whereas it is the other way around in the US. At long time horizons, there is a feedback between money and output in both economies. Key to our findings is that monetary disturbances have significant real effects and these effects last longer than it is assumed in real business cycle models.

  • 139.
    Habimana, Olivier
    et al.
    Jönköping University, Jönköping International Business School, JIBS, Economics. Department of Applied Statistics, College of Business and Economics, University of Rwanda, Kigali, Rwanda.
    Månsson, Kristofer
    Jönköping University, Jönköping International Business School, JIBS, Statistics.
    Sjölander, Pär
    Jönköping University, Jönköping International Business School, JIBS, Statistics.
    Testing for nonlinear unit roots in the presence of a structural break2015In: Festschrift in honor of Professor Ghazi Shukur on the occasion of his 60th birthday / [ed] Thomas Holgersson, Växjö: Linnaeus University Press , 2015Chapter in book (Other academic)
  • 140.
    Habimana, Olivier
    et al.
    Jönköping University, Jönköping International Business School, JIBS, Economics. Department of Applied Statistics, College of Business and Economics, University of Rwanda, Kigali, Rwanda.
    Månsson, Kristofer
    Jönköping University, Jönköping International Business School, JIBS, Statistics.
    Sjölander, Pär
    Jönköping University, Jönköping International Business School, JIBS, Statistics.
    Testing for nonlinear unit roots in the presence of a structural break with an application to the qualified PPP during the 1997 Asian financial crisis2018In: International journal of finance and economics, ISSN 1076-9307, E-ISSN 1099-1158, Vol. 23, no 3, p. 221-232Article in journal (Refereed)
    Abstract [en]

    This paper applies Monte Carlo simulations to evaluate the size and power properties in the presence of a structural break, for the standard Augmented Dickey-Fuller (ADF) test versus nonlinear exponential smooth transition autoregressive unit root tests. The break causes the tests to be undersized, and the statistical power considerably decreases. Moreover, the effect is intensified in small samples and very much increased for more persistent nonlinear series. As a remedy, we modify the standard ADF and exponential smooth transition autoregressive unit root tests in order to adjust for a structural break. This improves both the power and the size considerably, even though the empirical size still is lower than the nominal one. More persistent series are more affected by structural breaks, and the new tests are most powerful under the existence of a rather persistent nonlinear data generating process (which is an empirically relevant and common type of data generating process). The proposed tests are applied to investigate mean reversion in the real effective exchange rates of 5 East and Southeast Asian countries, taking into account the structural change in exchange rate regime brought about by the 1997 Asian financial crisis. The empirical findings corroborate our simulation results; the modified more powerful tests are able to reject the unit root in all 5 countries, whereas the tests that do not consider the structural break could only reject in one of these cases.

  • 141.
    Hacker, R. Scott
    et al.
    Jönköping University, Jönköping International Business School, JIBS, Economics, Finance and Statistics.
    Hatemi-J, Abdulnasser
    UAE University, Department of Economics and Finance.
    A bootstrap test for causality with endogenous lag length choice: theory and application in finance2012In: Journal of economic studies, ISSN 0144-3585, E-ISSN 1758-7387, Vol. 39, no 2, p. 144-160Article in journal (Refereed)
    Abstract [en]

    Purpose – In all existing theoretical papers on causality it is assumed that the lag length is known a priori. However, in applied research the lag length has to be selected before testing for causality. The purpose of this paper is to suggest that in investigating the effectiveness of various Granger causality testing methodologies, including those using bootstrapping, the lag length choice should be endogenized, by which we mean the data-driven preselection of lag length should be taken into account.

    Design/methodology/approach – The size and power of a bootstrap test with endogenized lag-length choice are investigated by simulation methods. A statistical software component is produced to implement the test, which is available online.

    Findings – The simulation results show that this test performs well. An application of the test provides empirical support for the hypothesis that the UAE financial market is integrated with the US market.

    Social implications – The empirical results based on this test are expected to be more precise.

    Originality/value – This paper considers a bootstrap test for causality with endogenous lag order. This test has superior properties compared to existing causality tests in terms of size, with similar if not better power and it is robust to ARCH effects that usually characterize financial data. Practitioners interested in causal inference based on time series data might find the test valuable.

  • 142.
    Hacker, R. Scott
    et al.
    Jönköping University, Jönköping International Business School, JIBS, Economics, Finance and Statistics.
    Hatemi-J, Abdulnasser
    United Arab Emirates University.
    Properties of Procedures Dealing with Uncertainty about Intercept and Deterministic Trend in Unit Root Testing2014In: Empirical Economics Review, ISSN 2222-9736, Vol. 3, no 1, p. 83-97Article in journal (Refereed)
    Abstract [en]

    The classic Dickey-Fuller unit-root test can be applied using three different equations, depending upon the inclusion of a constant and/or a time trend in the regression equation. This paper investigates the size and power properties of a unit-root testing strategy outlined in Enders (2004), which allows for repeated testing of the unit root with the three equations depending on the significance of various parameters in the equations. This strategy is similar to strategies suggested by others for unit root testing. Our Monte Carlo simulation experiments show that serious mass significance problems prevail when using the strategy suggested by Enders. Excluding the possibility of unrealistic outcomes and using a priori information on whether there is a trend in the underlying time series, as suggested by Elder and Kennedy (2001), reduces the mass significance problem for the unit root test and improves power for that test. Subsequent testing for whether a trend exists is seriously affected by testing for the unit root first, however.

  • 143.
    Hammarsten, Maria
    Jönköping University, School of Education and Communication, HLK, Learning Practices inside and outside School (LPS), Sustainability Education Research (SER).
    Det utvidgade matematiklärandet i särskolan2013Conference paper (Other academic)
  • 144. Hansbo, Anita
    Error estimates for the numerical solution of a time-periodic linear parabolic problem1991In: BIT Numerical Mathematics, ISSN 0006-3835, E-ISSN 1572-9125, Vol. 31, no 4, p. 664-685Article in journal (Refereed)
    Abstract [en]

    In this paper we consider the numerical solution of a time-periodic linear parabolic problem. We derive optimal order error estimates in Lz(f2) for approximate solutions obtained by discretizing in space by a Galerkin finite-element method and in time by single-step finite difference methods, using known estimates for the associated initial value problem. We generalize this approach and obtain error estimates for more general discretization methods in the norm of a Banach space B c L2(Ω), e.g., B = H10(Ω) or L(Ω). Finally, we consider some computational aspects and give a numerical example.

  • 145.
    Hansbo, Anita
    Jönköping University.
    Strong stability and non-smooth data error estimates for discretizations of linear parabolic problems2002In: BIT Numerical Mathematics, ISSN 0006-3835, E-ISSN 1572-9125, Vol. 42, no 2, p. 351-379Article in journal (Refereed)
    Abstract [en]

    We study smoothing properties of discretizations of a linear parabolic initial boundary value problem with a possibly non-selfadjoint elliptic operator. The solution at time t > 0 of this problem, as well as its time derivatives, are in Lr for initial values in Ls even when r > s. We show that similar strong stability results hold for discrete solutions obtained by discretizing in space by linear finite elements and in time by a class of A(Ξ)-stable implicit rational multistep methods (including single step methods as a special case) with good smoothing properties, as well as for certain combinations of single step methods. Most of our results are derived from the corresponding L2-bounds, shown by semigroup techniques, together with a discrete Gagliardo-Nirenberg inequality, and generalize previously known estimates with respect to admissible problems and time discretization methods. Our techniques make it possible to obtain, e.g., supremum norm error estimates for initial data which are only required to be in L1.

  • 146. Hansbo, Anita
    et al.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    An unfitted finite element method, based on Nitsche's method, for elliptic interface problems2002In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 191, no 47-48, p. 5537-5552Article in journal (Refereed)
    Abstract [en]

    In this paper we propose a method for the finite element solution of elliptic interface problem, using an approach due to Nitsche. The method allows for discontinuities, internal to the elements, in the approximation across the interface. We show that optimal order of convergence holds without restrictions on the location of the interface relative to the mesh. Further, we derive a posteriori error estimates for the purpose of controlling functionals of the error and present some numerical examples.

  • 147. Hansbo, Anita
    et al.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats G
    A finite element method on composite grids based on Nitsche's method2003In: Mathematical Modelling and Numerical Analysis, ISSN 0764-583X, E-ISSN 1290-3841, Vol. 37, no 3, p. 495-514Article in journal (Refereed)
    Abstract [en]

    In this paper we propose a finite element method for the approximation of second order elliptic problems on composite grids. The method is based on continuous piecewise polynomial approximation on each grid and weak enforcement of the proper continuity at an artificial interface defined by edges (or faces) of one the grids. We prove optimal order a priori and energy type a posteriori error estimates in 2 and 3 space dimensions, and present some numerical examples.

  • 148. Hansbo, Anita
    et al.
    Nylén, Per
    Models for the simulation of spray deposition and robot motion optimization in thermal spraying of rotating objects1999In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 122, no 2-3, p. 191-201Article in journal (Refereed)
    Abstract [en]

    In this paper we consider methods to simulate deposit build-up in thermal spraying and to optimize the robot motion so as to obtain the desired layer thickness. We derive a simplified mathematical model for spray deposition on a rotating large object with a smooth, rotationally symmetric, curved surface, yet allowing varying spray distance and direction. Further, we discuss how to obtain and incorporate an empirically determined deposit rate model. In particular, the simplified spray deposition model is chosen to make possible a reasonably cheap method to approximate a deposit rate from the results of layer thickness measurements. We also propose an iterative method to obtain good initial values for robot feed optimization. Numerical examples are presented. © 1999 Elsevier Science S.A.

  • 149.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    A mixed method for elasticity with the curl of displacements as a drilling degree of freedomManuscript (preprint) (Other academic)
    Abstract [en]

    We present a mixed method for the linearized elasticity equations with independent approximation of the curl of the displacements.The curl can be seen as a drilling degree of freedom allowing for coupling with rotating objects and the direct application of moments of force.

  • 150.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Nonconforming rotated Q1 tetrahedral element with explicit time stepping for elastodynamics2012In: International Journal for Numerical Methods in Engineering, ISSN 0029-5981, E-ISSN 1097-0207, Vol. 91, no 10, p. 1105-1114Article in journal (Refereed)
    Abstract [en]

    In this paper, we apply a rotated bilinear tetrahedral element to elastodynamics in R3. This element performs superior to the constant strain element in bending and, unlike the conforming linear strain tetrahedron, allows for row-sum lumping of the mass matrix. We study the effect of different choices of approximation (point- wise continuity versus edge average continuity) as well as lumping versus consistent mass in the setting of eigenvibrations. We also use the element in combination with the leapfrog method for time domain com- putations and make numerical comparisons with the constant strain and linear strain tetrahedra. 

1234567 101 - 150 of 337
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf