91Ó°ÊÓ

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 $48$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:

The researchers report that children taught by the teacher who claimed to be knowledgeable did significantly better $\left({\mathrm{χ}}^2=20.24,P<0.05\right)$. Explain why this result isn't valid.

Step by step solution

01

Given Information

The observed number of counts in four tries is as follows

${\mathrm{χ}}^2=20.24$

$P<0.05$.

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 $=\frac{\text{row total}×\text{column total}}{\text{total of all rown or columns}}$

Calculation:

The expected count will be

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

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

Unlock Step-by-Step Solutions & Ace Your Exams!

• Full Textbook Solutions

  Get detailed explanations and key concepts

• Unlimited Al creation

  Al flashcards, explanations, exams and more...

• Ads-free access

  To over 500 millions flashcards

• Money-back guarantee

  We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!