Stats30 Essay Example | Topics and Well Written Essays - 1500 words

Stats30 - Essay Example Answer True False   Question 4    If the data for a chi-square test for independence form a 2?2 matrix, then the value obtained for the chi-square statistic will be influenced by the sample size, but the value for the phi-coefficient will not. Answer True False   Question 5    In general, a large value for the chi-square statistic indicates that the null hypothesis is correct. Answer True False   Question 6    The phi-coefficient can be used to measure effect size for a chi-square test for independence provided there are exactly two categories for each of the two variables. Answer True False   Question 7    Which of the following is a characteristic of a nonparametric test? Answer a. A numerical score is required for each individual. b. The hypotheses concern population means and variances. c. The test requires assumptions about the population means or variances. d. none of the above   Question 8    The null hypothesis for the chi-square test for goodness of fit s pecifies ____. Answer a. proportions for the entire population b. proportions for the sample c. frequencies for the entire population d. frequencies for the sample   Question 9    Which of the following accurately describes the observed and expected frequencies in a chi-square test? Answer a. Both the observed and expected frequencies will always be whole numbers. b. The observed frequencies are always whole numbers but the expected frequencies may be decimals or fractions. c. The expected frequencies are always whole numbers but the observed frequencies may be decimals or fractions. d. Both the observed and expected frequencies may be decimals or fractions.   Question 10    A researcher obtains a value of ?8.50 for a chi-square statistic. What can you conclude because the value is negative? Answer a. The observed frequencies are consistently larger than the expected frequencies. b. The expected frequencies are consistently larger than the observed frequencies. c. There are large differences between the observed and expected frequencies. d. The researcher made a mistake. The value of chi-square cannot be negative.   Question 11    A chi-square test for independence is used to evaluate the relationship between two variables. If one variable is classified into four categories and the other variable is classified into two categories, then the chi-square statistic will have ____. Answer a. df = 3 b. df = 7 c. df = 8 d. cannot determine the value of df from the information provided   Question 12    The chi-square test for goodness of fit will produce a large value for chi-square when ____. Answer a. the sample proportions match the hypothesized population proportions b. the sample proportions are much different than the hypothesized population proportions c. the sample mean is close to the population mean d. there is a large difference between the sample mean and the population mean   Question 13    The sample data for a chi-square test are call ed ____. Answer a. expected frequencies b. observed frequencies c. expected proportions d. observed proportions   Question 14    A researcher would like to test the claim that 9 out of 10 doctors prefer Brand X. A sample of 60 doctors is obtained and each is asked to compare Brand X with another leading brand. The data show that 48 of the doctors picked Brand X. If these data are evaluated using a chi-square test f