Sorry, no chi-square We would prefer to learn from

Chapter , Problem R11.2

(choose chapter or problem)

Sorry, no chi-square We would prefer to learn from teachers who know their subject. Perhaps even preschool children are affected by how knowledgeable they think teachers are. Assign 48 three- and four-year-olds at random to be taught the name of a new toy by either an adult who claims to know about the toy or an adult who claims not to know about it. Then ask the children to pick out a picture of the new toy in a set of pictures of other toys and say its name. The response variable is the count of right answers in four tries. Here are the data:35 Correct Answers 01 2 3 4 Knowledgeable teacher 5 1639 Ignorant teacher 20 0301 The researchers report that children taught by the teacher who claimed to be knowledgeable did signifi- cantly better (C2 ? 20.24, P ? 0.05). Explain why this result isnt valid. s Use a chi-square test for homogeneity to determine whether the distribution of a categorical variable differs for several populations or treatments.