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In Exercises 7.1 to \(7.4,\) find the expected counts in each category using the given sample size and null hypothesis. $$ \begin{aligned} &\mathbf{7 . 3} \quad H_{0}: p_{A}=0.50, p_{B}=0.25, p_{C}=0.25 ;\\\ &n=200 \end{aligned} $$

Short Answer

Expert verified
The expected counts for categories A, B, and C are 100, 50, and 50, respectively.

Step by step solution

01

Find Expected Count for Category A

To find out the expected count for category A, multiply its proportion given by the null hypothesis (\(p_A=0.50\)) by the total size of the sample (\(n=200\)). Therefore, the expected count for category A is \(n*p_A = 200*0.50 = 100\)
02

Find Expected Count for Category B

To get the expected count for category B, multiply its proportion given by the null hypothesis (\(p_B=0.25\)) by the total size of the sample (\(n=200\)). Therefore, the expected count for category B is \(n*p_B = 200*0.25 = 50\)
03

Find Expected Count for Category C

To obtain the expected count for category C, multiply its proportion given by the null hypothesis (\(p_C=0.25\)) by the total size of the sample (\(n=200\)). Therefore, the expected count for category C is \(n*p_C = 200*0.25 = 50\)

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Most popular questions from this chapter

Give a two-way table and specify a particular cell for that table. In each case find the expected count for that cell and the contribution to the chi- square statistic for that cell. \((\mathrm{B}, \mathrm{E})\) cell $$ \begin{array}{l|rrrr|r} \hline & \text { D } & \text { E } & \text { F } & \text { G } & \text { Total } \\ \hline \text { A } & 39 & 34 & 43 & 34 & 150 \\ \text { B } & 78 & 89 & 70 & 93 & 330 \\ \text { C } & 23 & 37 & 27 & 33 & 120 \\ \hline \text { Total } & 140 & 160 & 140 & 160 & 600 \\ \hline \end{array} $$

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