Question

Does it appear that the pattern of AIDS cases in Santa Clara County corresponds to the distribution of ethnic groups in this county? Why or why not?

Short answer

No, the hypothesis test revealed that the ethnicity of AIDS cases in Santa Clara County does not match that of the overall population.

Step-by-step solution

Given Information

The following data are real. The cumulative number of AIDS cases reported for Santa Clara County is broken down by ethnicity as in Table 11.29.

$\begin{array}{|ll|}\hline \text{Ethnicity}& \text{Number of Cases}\\ \text{White}& 2,229\\ \text{Hispanic}& 1,157\\ \text{Black/African-American}& 457\\ \text{Asian, Pacific Islander}& 232\\ & \text{Total}=4,075\\ \hline\end{array}$

The percentage of each ethnic group in Santa Clara County is as in Table 11.30.

$\begin{array}{|lll|}\hline \text{Ethnicity}& \begin{array}{l}\text{Percentage of total county}\\ \text{population}\end{array}& \begin{array}{l}\text{Number expected (round to two}\\ \text{decimal places)}\end{array}\\ \text{White}& 42.9\%& 1748.18\\ \text{Hispanic}& 26.7\%& \\ \begin{array}{l}\text{BlacklAfrican-}\\ \text{American}\end{array}& 2.6\%& \\ \begin{array}{l}\text{Asian, Pacific}\\ \text{Islander}\end{array}& 27.8\%& \\ & \text{Total}=100\%& \\ \hline\end{array}$

Explanation

The graph below shows the relationship between ethnicity and the number of AIDS cases.

The graph below depicts the relationship between ethnicity and total population proportions.