Question 1

If we wanted to know if there was a statistically significant difference between males and females on the average number of soft drinks they consumed during a week and our test calculated a z of 6.43,this would mean there was no difference in the average number of drinks consumed between the two groups.

Accepted Answer

A z score of 6.43 indicates a very large difference between the two groups, and is unlikely to be due to chance. Therefore, it suggests that there is a statistically significant difference in the average number of drinks consumed between males and females.

Question 2

When testing the difference between the percentages of two groups,XL Data Analyst performs this task by the command: Compare-4+ Group Percents.

Accepted Answer

This command does not exist in XL Data Analyst. There are various functions and tools in Excel that can be used to calculate the difference between two percentages, but there is no specific command called Compare-4+ Group Percents.

Question 3

When comparing differences between the percentages of two groups and our z is 1.98 at the 95% level of confidence,we may conclude the two percentages are significantly different.

Accepted Answer

At a 95% level of confidence, a z score of 1.98 falls beyond the critical value of 1.96 (which is the z value for 95% confidence level), indicating that the differences between the percentages of the two groups are statistically significant. Therefore, the answer is A, true.

Question 4

The output for ANOVA in your XL Data Analyst software provides a table that shows you group averages and which are significantly different if ANOVA finds the null hypothesis is not supported.

Accepted Answer

The output for ANOVA in XL Data Analyst does provide a table that shows group averages and indicates which groups are significantly different if the null hypothesis is rejected.

Question 5

If the XL Data Analyst has reported that the hypothesis of equal percents (the null hypothesis)is "not supported," then there is a true difference between the two group percentages.

Accepted Answer

The answer of If the XL Data Analyst has reported...

Question 6

When we test for the differences between percentages for two groups the null hypothesis is that the difference in the two group's population parameters is over 30.

Accepted Answer

The statement is not correct. The null hypothesis is usually that there is no significant difference between the percentages in the two groups, and it is the alternative hypothesis that suggests there is a difference beyond chance variation. Additionally, the value of 30 has no relevance to this hypothesis test.

Question 7

Statistical significance is the same thing as practical significance.

Accepted Answer

Statistical significance refers to the probability of obtaining a result by chance, while practical significance refers to the importance or relevance of the result in real-world applications. They are not the same thing.

Question 8

Analysis of variance is used to test the difference between percentages between more than two groups.

Accepted Answer

Analysis of variance (ANOVA) is used to test the difference between means among more than two groups, not percentages.

Question 9

The word "variance" in the name "analysis of variance" is misleading.

Accepted Answer

Although "variance" is used in the name, the actual purpose of the analysis is to compare means rather than variances.

Question 10

ANOVA is not an analysis of the standard deviations of the groups.

Accepted Answer

ANOVA (Analysis of Variance) is primarily focused on comparing the means of three or more groups, not their standard deviations.

Question 11

When the difference is deemed to be important and useful to the marketing manager,then it has practical significance.

Accepted Answer

Practical significance refers to the level of importance or usefulness of a difference or result to a particular decision or action. If the difference is determined to be significant enough to impact marketing decisions, then it has practical significance. Therefore, the statement is true.

Question 12

The apex of the sampling distribution of the difference between two percents is zero to represent the null hypothesis.

Accepted Answer

The apex (highest point) of the sampling distribution of the difference between two percents is indeed zero to represent the null hypothesis, which states that there is no significant difference between the two percentages being compared. This means that if we were to plot a histogram or bell curve of all possible sample differences between two percents assuming the null hypothesis, the center or peak of the curve would fall on 0.

Question 13

The proper command sequence to run ANOVA using your XL Data Analyst software is: COMPARE-3+ GROUP AVERAGES.

Accepted Answer

This is the correct command sequence to run ANOVA using XL Data Analyst software.

Question 14

The formula for comparing differences between the percentages of two groups uses the percentages from each group in the numerator.

Accepted Answer

The formula for comparing differences between the percentages of two groups indeed uses the percentages from each group in the numerator, typically in a format similar to (Percentage1 - Percentage2) to calculate the difference.

Question 15

If we wanted to know if there was a statistically significant difference between males and females on the average number of soft drinks they consumed during a week we would be testing for the difference between averages for two groups.

Accepted Answer

Testing for the difference between averages for two groups is a typical scenario for a two-sample t-test, which can be used to determine if there is a statistically significant difference between the means of two groups. In this case, we have two groups (males and females) and we want to compare the average number of soft drinks they consumed during a week, so a two-sample t-test would be appropriate.

Question 16

There is an appropriate test to compare two averages when there are no groups such as male v.female.The test calculates differences between the averages of two different variables.

Accepted Answer

The paired samples t-test (also known as the dependent samples t-test) is used to compare the means of two related groups or conditions, effectively handling situations where there are not distinct groups like male vs. female but rather two variables for the same group.

Question 17

When testing the difference between the averages of two groups,XL Data Analyst performs this task by the command: Compare-2 Group Averages.

Accepted Answer

XL Data Analyst performs this task by the command: Compare-2 Group Averages.

Question 18

Because we have two samples when testing the significance of the difference between two percentages instead of the one that we worked with for a hypothesis test,the standard error term is calculated differently,called the standard error of the difference between two percentages.

Accepted Answer

The standard error term is indeed calculated differently for two samples when testing the significance of the difference between two percentages, and it is called the standard error of the difference between two percentages.

Question 19

Directional hypotheses are NOT feasible in the case of tests of statistically significant differences.

Accepted Answer

Directional hypotheses are feasible and often used in tests of statistically significant differences, as they predict the direction of the expected difference between groups or conditions.

Question 20

When testing the difference between the percentages of two groups,XL Data Analyst requires users to enter both the grouping variable and the target variable.

Accepted Answer

XL Data Analyst requires users to enter both the grouping variable and the target variable when testing the difference between the percentages of two groups.

Quiz 13: Finding Differences