Thinking about Influences on Number Skills and Simple Arithmetic for Children Aged 4-8 Dr Silke Göbel & Dr Anuradha J. Bakshi INTRODUCTIONS YORK, England Frankfurt, Germany FRANKFURT, Germany MUMBAI, India BANGALORE, India ٣ 23 + 65 百 427 不可思议 Typical development From Butterworth (2010) Overview • • • • • • • Preverbal number skills Counting Number Symbols Arithmetic Working memory Cross-cultural differences Struggling with math PREVERBAL NUMBER SKILLS from Dehaene (1999) Subitizing Counting Subitizing from Dehaene (1999) Human Infants Human Infants Xu & Spelke (2000) • 6-month-old infants discriminate 8 from 16 6-month-old Infant Numerical Discrimination Ratios they could do Ratios they could not do 4 vs 8 4 vs. 6 8 vs 16 8 vs. 12 16 vs 32 16 vs. 24 1: 2 YES 2:3 NO From Brannon (2005) Development of Number Sense Acuity Halberda & Feigenson (2008) • 3, 4, 5, 6 year olds & adults Development of number sense acuity Halberda & Feigenson (2008) • 3, 4,5, 6 year olds & adults Weber Fraction • Equal to the difference between the two numbers divided by the smaller number • The closer the number is to zero the better the number discrimination • Example: – ratio 7:8 – Weber fraction (8-7/7) = 0.14 Predictors of math performance: Weber fraction Halberda et al. (2008) COUNTING Group Activity USE YOUR FINGERS! HOW DO YOU COUNT? Finger Counting • Mundurucu finger counting WHICH HAND FIRST? from Lindemann et al. (2011) A Small Survey of Counting Up To 10 Using Fingers/Hands in India (n=54) • • • • Children, young adults & older adults Both female and male Grown up in villages and cities Grown up in different parts of India (e.g., Delhi, Chandigarh, W. Bengal, Rajasthan, Gujarat, Mumbai, Chennai) • From different communities WHICH HAND FIRST? • Handedness? • Orthography? • Yet, fewer count starting with the left hand; most start with their right hand. Right-starters outnumber the left-starters (40 out of 54). • ―Finger counting habits are related to eye scanning habits in visual perception outside of reading‖ (Lindemann et al., 2011, p. 574). WHICH FINGER FIRST? • Thumb? • Index finger? • Little finger? • Smallest finger heuristic more representative of the Indian participants (39 out of 54 participants). SOME REPEATED TYPES OF COUNTING UP TO 10 USING FINGERS/HANDS SOME REPEATED TYPES OF COUNTING UP TO 10 USING FINGERS/HANDS SOME REPEATED TYPES OF COUNTING UP TO 10 USING FINGERS/HANDS SOME REPEATED TYPES OF COUNTING UP TO 10 USING FINGERS/HANDS One-third of the participants counted using phalanges (n= 18). Eight participants counted using 4 subdivisions/finger. Counting • Children typically learn to count before they go to school • Gelman & Gallistel’s how to count principles: – 1-1 principle (count each thing once) – Stable order principle (use count words in fixed order) – Cardinality principle (last count word represents number of things counted) – Abstraction principle (any collection of objects can be counted) – Order irrelevance principle (order of counting objects doesn’t affect outcome) • Counting skills form the basis of early arithmetic skills Counting principles Counting direction Counting direction Percentage of adults 100 left starting right starting 80 60 40 20 0 Left to right Right to left Mixed Illiterate Reading Experience from Shaki, Fischer & Göbel (submitted) Counting direction Reading Direction 100 Left to right Mixed Right to left left starting right starting Percentage of children 80 60 40 20 0 pre-school school pre-school school pre-school school from Shaki, Fischer & Göbel (submitted) COUNTING DIRECTION: INDIA NUMBER SYMBOLS LEFT OR RIGHT? WHICH NUMBER IS LARGER? 2 8 7 1 9 3 8 9 When is it easier to identify the larger number? Symbolic Distance Effect from Butterworth (1999) Predictors of Math Performance: Numerical Distance Effect De Smedt et al. (2009): N = 42 6-year-olds, tested again after 1 year 2 8 7 3 1 9 Was is it easy to identify the larger number? Was there any distraction? Size Congruity Effect • In the numerical comparison task: size congruency effect at all ages • In the physical comparison task: incongruency only affected older children and adults • Automatization of number processing develops gradually Butterworth (1999) ARITHMETIC 2+ 5=? Problem Size Effect - Addition from Ashcraft (1995) The Development of Arithmetic Skills • At school children master single addition first, followed by subtraction, multiplication and division (going on to multi-digit numbers and problems associated with place value) Single digit addition may be solved in a number of (increasingly sophisticated) ways 2 +5 = ? Could you share what are some of the ways in which a child may add this? How do you add this? – Count all strategy (2+3 –> 1, 2 …3, 4, 5) – Count on strategy (2+3 –> 2 …3, 4, 5) – Min strategy (2+3 –> 3 … 4, 5) – and this involves the commutativity principle (order or addends irrelevant) – Finally with practice problems are solved by direct retrieval from LTM (number fact knowledge) Strategies and Problem size Siegler & Shrager (1984) Addition in 4- and 5 year old children • Use a variety of strategies: – – – – 64% of the time: retrieval 15% counting on fingers 8% counting without finger use 13% using fingers without counting Strategies and Problem size Siegler (1987) Addition in 6- and 8-year-old children • Use a variety of strategies: – – – – – 35% of the time: retrieval 36% counting with minimum addend 8% counting with all digits 7% decomposition into simpler problems 14% guessed or failed to answer WORKING MEMORY Baddeley & Hitch’s Working Memory Model (1974) Articulatory loop Central Executive Visuo-spatial Sketch-pad B&H Working memory model • The model distinguishes between two modality specific stores (the phonological loop and the visuo-spatial sketch pad) and an amodal attentional control system (the Central Executive) • Deficits in any of these components might affect the development of arithmetic skills Predictors of math performance: working memory In most studies (e.g. Passolunghi et al., 2007) the central executive was a unique predictor of later mathematics achievement Age-related differences with regard to the contribution of the slave systems to mathematics performance have been suggested (De Smedt et al. ,2009) CROSS-CULTURAL DIFFERENCES Cross-cultural differences in math performance • Children from Japan, Korea and China outperform American and European children on tests of math ability • East Asian subjects produce smaller problem-size effects than do North Americans (Campbell & Xue, 2001) • The Hindu-Arabic base-10 system is the foundation of modern arithmetic, and knowledge of base-10 is critical to children’s math competence: East Asian students tend to have a better grasp of the base-10 system (Geary, 2006) Cross-cultural differences in math performance What do you think are the possible reasons explaining these differences? Possible factors: – Cultural influences – Linguistic influences Cultural Influences • Influence of pre-school education • Quantity and quality of math teaching (Perry et al., 1993) • Strategies used in problem solving problems (Fuson & Kwon, 1999) • Attitudes of teachers, parents and children Group Activity 1. MATH TEACHING 2. ATTITUDES OF TEACHERS, PARENTS & CHILDREN Linguistic Influences • Number Words Activity in small groups NUMBER WORDS IN YOUR LANGUAGE S??? Cultures differ in the number of number words! • Smallest number word in the languages you know? • Largest number word in the languages you know? English Short Scale Long Scale (US & Modern British) (Continental Europe & Older British) Sextillion 1024 1036 Octillion 1027 1048 Centillion 10303 10600 ० शन् ू य shoonya १,००० १,००,००० १,००,००,००० १,००,००,००,००० १,००,००,००,००,००० हजार ऱाख करोड़ अरब खरब hajaara laakh karod arab kharab A few large numbers used in India by about 5th century BCE (Ifrah) • • • • • • • • ahaha (अहाहा) —1070 ababa (अबाबा). —1077 atata (अटाटा) —1084 soganghika (सोगान्घीका) —1091 uppala (उप्पाऱा) —1098 matsya (मत्स्य) —10600infinities dasavatara (दशावतारा) —1010000infinities jyotiba (ज्योततबा) —1080000infinities Cultures differ in the number of number words! • Two tribes in the Amazonian area of Brazil have very small lexica of number words: – the Pirahã (Frank, Everett, Fedorenko, Gibson, 2008; Gordon, 2004) – the Mundurucu (Dehaene, Izard, Spelke, & Pica, 2008; Pica et al., 2004). Number Vocabulary Size & Numerical Cognition • The Pirahã have only three number words: – ―hói‖ (one) – ―hoí‖ (two) – ―aibaagi‖/―aibai‖ (many). • When the Pirahã were tested in number discrimination and reproduction tasks, their performance with quantities larger than three was poor. Numeral 1 2 3 4 5 6 7 8 9 10 Modern English Old English/ Medieval English (masculine; feminine) German Hindi one ān; forma eins ek two twēgen, twā, tū; ōðer zwei do three þrīe, þrēo; þridda drei teen four fēower; fēorða vier chaar five fīf; fīfta fünf panch six six; sixta sechs cheh seven seofon; seofoða sieben saat eight eahta; eahtoða acht aath nine nigon; nigoða neun non ten tīene; tēoða zehn das Numeral 11 12 13 14 Modern English eleven Old English/ Medieval English (masculine; feminine) endleofan; endleofta German Hindi elf gyaarah twelve twelf; twelfta zwölf baarah thirteen þrēotīene; þrēotēoða dreizehn terah fourteen fēowertīene; fēowertēoða vierzehn choudah 15 fifteen 16 sixteen 17 seventeen fīftīene; fīftēoða fünfzehn pandarah sixtīene; sixtēoða sechzehn solah seofontīene; seofontēoða siebzehn satrah 18 eighteen 19 nineteen 20 twenty eahtatīene; eahtatēoða achtzehn atharah nigontīene; nigontēoða neunzehn unnees twentig; twentigoða zwanzig bees Numeral Modern English 20 twenty 21 twenty-one Old English/ Medieval English (masculine; feminine) twentig; twentigoða German Hindi zwanzig bees ān and twentiġ (masculine einundzwanzig ikkees form) 22 23 24 39 40 43 55 56 twenty-two twēgen and twentiġ zweiundzwanzig baiees twenty-three þrīe and twentiġ dreiundzwanzig thaiees twenty-four fēower and twentiġ vierundzwanzig chaubees thirty-nine nigon and þrītig neununddreißig unnchalis forty fēowertig vierzig chalis forty-three þrīe and fēowertig dreiundvierzig tetalis fifty-five fīf and fīftig fünfundfünfzig pachpann fifty-six six and fīftig sechsundfünfzig chhappan Regularity of the number system English French Japanese One Un/une Ichi Two Deux Ni Three Trois San Four Quatre Shi Ten Dix Juu Eleven Onze Juu-ichi Twelve Douze Juu-ni Twenty Vingt Ni-juu Twenty-one Vingt-et-un Ni-juu-ichi From Towse & Saxton (1998) WHAT DIFFERENCES DO YOU OBSERVE IN THE NUMBER WORDS ACROSS THE DIFFERENT LANGUAGES? • For example, in saying 43—what are the differences across the languages? • In your opinion, which way is a better system? • Why? Number Words 43 In English: ‘Forty-three’ In German: ‘Dreiundvierzig’ Number Words 43 In English: ‘Forty-three’ In German: ‘Dreiundvierzig’ Number Words 43 In English: ‘Forty-three’ In German: ‘Dreiundvierzig’ Number Words consistent 43 In English: ‘Forty-three’ In German: ‘Dreiundvierzig’ Number Words inconsistent 43 In English: ‘Forty-three’ In German: ‘Dreiundvierzig’ Number Words inconsistent 43 In English: ‘Forty-three’ In German: ‘Dreiundvierzig’ Number Words inconsistent 43 In English: ‘Forty-three’ In German: ‘Dreiundvierzig’ Number Words • Consistent or inconsistent? • The consistency or inconsistency of a numberword is a matter of perspective. Number Words • More errors in transcoding when inconsistent • More mistakes in number comparison • Decade distance (DD): • Unit-decade compatibility compatible incompatible 32 37 62 57 small large 32 32 87 47 Inversion for Austrians From Pixner et al. (2011) Summary of Linguistic influences that may be relevant (cf. Dowker, 2005): • Whether the language includes number words at all and if there is an upper limit • Whether there is a written number system • The regularity of the spoken number system • The degree and consistency of mapping between the spoken and the written number system NUMBER GAMES? Which number games or games involving numbers did you play as a child? Games Involving Numbers Played by Children in India Board Games Board Games Card Games Traditional Indian Number Games : Pallanguli Traditional Indian Number Games 7-Tiles (Pithoo; Saat Pathar; Lagori): Other Games/Play Involving Numbers • • • • Counting while skipping Hopscotch (Stapu, Pandee) Gittak (8 pebbles) Maintaining a score in many outdoor games such as badminton STRUGGLING WITH MATH Group Activity WHAT ARE THE CHILDREN STRUGGLING WITH ? What is Mathematics Disorder? Slow, limited or otherwise faulty development of number processing, counting and/or calculation in children who do not otherwise give evidence of gross neurological or psychiatric disability. A case study Claire • 8 years old, second grade • average cognitive skills, good motivation and attention • struggles in math in school • developmental lag in counting, understanding of place value • difficulties in addition and subtraction of one digit numbers – about 80% and 40 % accurate, using finger counting An adult case Mathematical Disorder DSM-IV Diagnostic Criteria Discrepancy definition: ―mathematical ability, as measured by individually administered standardized tests is substantially below that expected given the person’s chronological age, measured intelligence and ageappropriate education‖ Prevalence of MD • Lewis, Hitch & Walker (1994) – 9 and 10 year old children (N = 1206) – Criterion : Standard score in math less than 85 – Normal nonverbal IQ – Reading at or above standard score of 90 • 1.3 % specific difficulty in maths • 2.3 % reading and maths problems • Total of 3.6 % mathematics disorder Thus comorbidity between MD and RD is common. MD/RD children tend to have more severe problems with Math. Prevalence of MD • Share, Moffitt & Silva (1988) in New Zealand: 11.2% • Large US study by Baker & Cantwell (1985): 6% • In Israel, Gross-Tsur, Manor & Shalev (1996): 6.5% Mathematics Disorder • What is there to explain? – – – – Inaccurate calculations Counting errors Slow on number fact retrieval Usage of immature strategies for calculation (finger counting) Cognitive Deficits in MD • Four main ideas: – Number (magnitude) representation problems: • Basic difficulties in representing numbers – Counting problems – Number fact storage problems: • Difficulties in learning and storing the solutions to problems – Attentional control and working memory problems • Problems in executing the process required to solve a problem Cognitive Deficits in MD • Four main ideas: – Number (magnitude) representation problems: • Basic difficulties in representing numbers – Counting problems Number Sense Deficit – Number fact storage problems: • Difficulties in learning and storing the solutions to problems – Attentional control and working memory problems • Problems in executing the process required to solve a problem Cognitive Deficits in MD • Four main ideas: – Number (magnitude) representation problems: • Basic difficulties in representing numbers – Counting problems Number Sense Deficit – Number fact storage problems: • Difficulties in learning and storing the solutions to problems – Attentional control and working memory problems • Problems in executing the process required to solve a problem Working Memory Deficit Other Influences: Math Anxiety (Dowker, 2005; Geary, 2006) • Rate your math anxiety on a 10-point scale • What explains your rating? Other Influences: Math Related Self-Conceptions of Learners (de Corte & Verschaffel, 2006) • Share some of the math-related selfconceptions you have? • How do these impact math performance? ―These beliefs exert a powerful influence on students’ evaluation of their own ability, on their willingness to engage in mathematical tasks, and on their ultimate mathematical disposition‖ (in de Corte & Verschaffel, 2006, p. 121) Summary 1 Preverbal infants can already possess an ability to discriminate numerosities (ratio-dependent) This ability gets better with age Counting lays the foundations for arithmetic Summary 2 Arabic numerals have to be learned ―We learn number processing, and in particular arithmetic and higher mathematical skills, through formal instruction (Goebel, Shaki, & Fischer, 2011, p. 544)‖. Research into longitudinal predictors of math skills is in its infancy A comprehensive developmental model of number processing is missing