01758nas a2200217   4500008004100000245006600041210006500107260000900172300001400181490000600195520108700201653002401288653001501312653002401327653001401351100001301365700001501378700001301393700001701406856011701423       2010                        eng d00aExtraction of children's friend relations from activity level0 aExtraction of childrens friend relations from activity level  c2010  a270 - 2750 v83 aThis paper proposes the method to extract the friendship relations of children by using motion sensors. Children learn to fit into society through living in a group, and it's greatly influenced by their friend relations. Although preschool teachers need to observe them to assist in the growth of children's social progress and support the development each child's personality, only experienced teachers can watch over children while providing high-quality guidance. To resolve the problem, this paper proposes a mathematical and objective method that assists teachers with observation. It uses numerical data of activity level recorded by pedometers, and the authors make tree diagram called dendrogram based on hierarchical clustering with recorded activity level. Also, the authors calculate children's "breadth" and "depth" of friend relations by using more than one dendrogram. When the authors record children's activity level in a certain kindergarten for two months and evaluated the proposed method, the results usually coincide with remarks of teachers about the children.10aAcceleration sensor10aClustering10aFriendship relation10aPedometer1 aHaga, H.1 aKaneda, S.1 aKono, A.1 aShintani, K.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-79960659287&partnerID=40&md5=0f94aed0a83203638341b37b6cb7cc8b