SOLVED

21) When a computed z value (for a test for differences between two percentages), 4.21, is larger than the standard z value, 1.96, then this amounts to: A) support for the null hypothesis; the two percentages are differen.t B) no support for the null hypothesis; the two percentages are NOT different. C) support for the null hypothesis; the two percentages are NOT different. D) no support for the null hypothesis; the two percentages are different. E) having to recalculate as the z value is not utilized for testing the differences between two percentages. 22) Which of the following is NOT true of a differences test? A) With the null hypothesis, the arithmetic difference between one parameter and another is 0. B) With both hypotheses, it is impossible to “guess” differences before testing. C) With the null hypothesis, the statistical test begins with the assumption that the two percentages (or means) are exactly the same value. D) The alternative hypothesis is that the two percentages (or means) are not the same value. E) With the alternative hypothesis, the difference between parameters is not 0. 23) Which of the following commands would be used to test for the significant differences between two percentages using XL Data Analyst? A) “Summarize,” “2 Group Percents,” select two target variables, then select one grouping variable, and “OK” B) “Compare,” “2 Group Percents,” select two grouping variables, and “OK” C) “Compare,” “2 Group Percents,” select two target variables, and “OK” D) “Summarize,” “2 Group Percents,” select two grouping variables, then select one target variable, and “OK” E) “Compare,” “2 Group Percents,” select two grouping variables, then select one target variable, and “OK” 24) The only difference in the procedure for testing the significance of the difference between two averages versus testing the significance between two percentages is: A) testing for averages looks for differences in a metric variable and percentages looks for differences in a categorical variable. B) testing averages require using the z value and percentages require using the p value. C) testing averages requires a 99% level of confidence whereas a level of 95% is sufficient for testing percentages. D) when testing for 95% level of confidence with averages the z value is 1.96 and for percentages it is 1.64. E) testing averages requires two more steps than the testing with percentages. 25) Which of the following commands would be used to test for the significant differences between two percentages using XL Data Analyst? A) “Summarize,” “2 Group Averages,” select two target variables, then select one grouping variable, and “OK” B) “Compare,” “2 Group Averages,” select two grouping variables, and “OK” C) “Compare,” “2 Group Averages,” select two target variables, and “OK” D) “Summarize,” “2 Group Averages,” select two grouping variables, then select one target variable, and “OK” E) “Compare,” “2 Group Averages,” select two grouping variables, then select one target variable, and “OK” 26) Directional hypotheses are also feasible in the case of tests of statistically significant differences. The only difference is: A) ignore the sign of the z value because we are only looking for a significant difference; the size of the z value. B) that the z value for 95% is 1.64 and for 99% is 2.33. C) we need to not only look at the z value but the sign to ensure the direction. D) that the alternative hypothesis is called the directional hypothesis. E) the null hypothesis states the opposite direction of difference to what the directional hypothesis is proposing. 27) The standard error of a difference curve has a mean of: A) 1. B) 0. C) 1.96 D) 2.58 E) -1. 28) Assume you have two questions of the same format, a 5-point scale measuring importance level. One question measures the importance of prices in the selection of a restaurant and the other measures the importance of food quality. If you want to know if the two mean scores of each question are significantly different, you would use: A) a z test of the differences between two percentages. B) the procedure for testing the significance of the difference between two means from two different groups. C) an independent samples t test. D) a two mean comparison z test. E) a two question, mean comparison test. 29) Let’s say we wanted to see if there was a significant difference between your class’s GPA when you were all freshmen and your class’s GPA today. What is the proper test for differences? A) differences between percentages of 2 groups B) differences between percentages of 2 variables in one group C) differences between 2 research projects D) differences between averages of 2 variables in one group E) differences between averages of 2 groups 30) Let’s assume there are freshman, seniors, and graduate students in your class and we want to know if their average GPAs differ. What is the proper statistical test? A) t test B) Means differences test C) Summarization of means test D) ANOVA E) z test