Consider a claim that 60% of the mice in a region have parasitic infections. We can use an χ² goodness-of-fit test to test whether the proportion is indeed 60%. Consider a study in which we collect a random sample of 50 mice and 36 have infections. What is the χ²value we would obtain?

Question

Quizplus · Accepted Answer

The chi-square value is calculated using the formula: $\chi^2 = \sum \frac{(O - E)^2}{E}$, where $O$ is the observed frequency and $E$ is the expected frequency. For the given problem, we expect 60% of the 50 mice to have infections, which is 30 mice. The observed number is 36. Plugging into the formula gives: $\chi^2 = \frac{(36-30)^2}{30} + \frac{(14-20)^2}{20} = 3.000$.

Consider a Claim That 60% of the Mice in a Region