Sorry, no chi-square We would prefer to learn from teachers who know their subject. Perhaps even pre-school children are affected by how knowledgeable they think teachers are. Assign 48three- 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:

The researchers report that children taught by the teacher who claimed to be knowledgeable did significantly better χ2=20.24,P<0.05. Explain why this result isn't valid.

Short Answer

Expert verified

There are 6 cells which have expected count less than 5.

Step by step solution

01

Given Information

The observed number of counts in four tries is as follows

χ2=20.24

P<0.05.

02

Explanation

Concept used:

For chi square test to be used, in each cell the expected count should be more than or equal to 5.

Formula used:

Expected count =row total×column totaltotal of all rown or columns

Calculation:

The expected count will be

Using the concept aforementioned, there are 6cells which have expected count less than 5.

Hence, the result isn't valid because chi square can't be used.

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