Modeling the Developmental Process of Depth Perception of Elementary Students

1. Modeling the Developmental Processof Depth Perception of Elementary Students Naoko Yoshii, Masami Takata, Kazuki Joe Graduate School of Humanity and Science Nara Women’s University

2. Outline of presentation • Introduction Background and objectives • Short review Recognition of two dimensional images • Experiment • Modeling • Conclusions

3. Background • H.A.Witkin: Spatial cognition → men's sense of direction is better than that of women • Infants’ depth perception

4. Objectives • To make the developmental differences in depth perception of two dimensional images between boys and girls clear. • To construct a developmental model of depth perception of each image by gender.

5. Outline of presentation • Introduction Background and objectives • Short review Recognition of two dimensional images • Experiment • Modeling • Conclusions

6. Short review Hock：two-stage model manipulation of schema Second stage ・Can manipulate and understand schema creation of schema First stage ・ Create schema ・ Can not manipulate schema

7. Short review Piaget : developmental stages ・7,8 ~ 11 years old -- development of ability to manipulate and understand schema ・2 ~7 years old -- Create schema -- No manipulation of schema

8. Short review Hock：two-stage model Piaget No distinctions by gender. Boys Girls We analyzed the experimentaldata of each image by gender. edge images color images gray scale images

9. Outline of presentation • Introduction Background and objectives • Short review Recognition of two dimensional image • Experiment • Modeling • Conclusions

10. Experiment • Depth perception of two dimensional images --edge , gray scale, color • In the order of edge, gray scale and color • 85 children ( 7 – 11 years old ) • The method of paired comparison ・ “ I do not understand ”　→　 mistake ・ “ They are the same ” →　 mistake Table 1. Object child

11. Experiment • 18 images : 6 photos, each one rendered 3 different ways (edge, gray scale, and color) • 20 questions about the 6 photos • Images size are 89㎜× 127㎜

12. Experiment

13. Experiment

14. Outline of presentation • Introduction Background and objectives • Short review Recognition of two dimensional images • Experiment&Results • Modeling • Conclusions

15. Experiment results • Result of each image Figure 7. Girl’s graph Figure 6. Boy’s graph

16. Experiment results • Accuracy by image type --edge images are low, color images are high • Boys’ accuracy and girls’ accuracy • Most accurate age • 9 ~ 10 year old girls rapid development

17. Results & discussions Figure 8. The indoor image of a kindergarten school (Q2_4) “Which is farther away, this (the eaves outside the room ) or this (the glass door in room)?’’ edge of eaves outside the room glass door in room Correct answer rate of the color image; --seven years old ; 61.11% (boys 88.89％，girls 33.33％） --eight years old ; 94.44％ (boys 100％，girls 87.50％）

18. Experiment results Experiment result The differences in development Construction of a developmental model

19. Outline of presentation • Introduction Background and objectives • Short review Recognition of two dimension images • Experiment • Modeling • Conclusions

20. Modeling • Regression equation : y=a/x+b • Obtaining constant a and constant b to minimize the following expression. (1) • Partial differentiation for constants aand b • Simultaneous equation

21. Modeling • Edge image: Boy‘s developmental model ： ｙ＝ -1.0281／ｘ＋0.8896　 （2） Girl’s developmental model ： ｙ＝ -2.0460／ｘ＋1.0578 （3） • Gray scale image： Boy’s developmental model： ｙ＝ -1.7732／ｘ＋1.0333 （4） Girl’s developmental model ： ｙ＝ -1.7210／ｘ＋1.0211 （5） • Color image： Boy’s developmental model ： ｙ＝ -1.3522／ｘ＋1.0034 （6） Girl’s developmental model ： ｙ＝ -0.8196／ｘ＋0.9297 （7） 　（ , ｘ：age, ｙ：correct answer rate）

22. Conclusions • Our experiment results make it clear that there is a difference in the development of depth perception of two dimensional images among boys and girls. • In the near future, using the results of this research of age and sex,we hope to develop an effective instructional strategy for the field of education.

23. That’s all for my presentation. Thank you very much.