Exam 13: Bivariate Statistical Analysis: Tests of Differences

A packaged-goods company wishes to know which of the three packaging types is most effective for consumers in control group vs uncontrolled group setting. This can be measured through paired samples t-test.

To examine changes in attitudes among an experimental group in a pretest-post-test design, an independent samples t-test would be appropriate.

In an analysis of variance, the variability of the group means about a grand mean is calculated by:

If the F-value is large, the results are likely to be insignificant.

In an analysis of variance, the F-ratio is calculated by:

When the sample size is large, the Z-test is a close approximation to the t-test.

Red Cross Blood Service hypothesise that men make, on average, a higher number of donor visits per year than women. To examine this hypothesis, an appropriate statistical test would be a(n):

Given the limitation of group heterogeneity in experimental designs, researchers may wish to use some kind of pre-test posttest design.

In comparing the difference of the means between two groups, the null hypothesis can be stated as:

If dependent variable is a ranking data, then which of the following test is applied?

In the independent samples t-test, the variances are assumed to be equal for the two samples when the significant value of the 'Levene's test for equality of variances' is significant.

An ANOVA is applied on one metric variable and one non-metric variable with two groups.

In an analysis of variance, the systematic variation of scores between the groups is due to individual differences.

To test differences in means between two or more groups, we need to ensure that the variable we are taking the mean of is ordinal-scaled.

The t-test is used when the number of observations (sample size) in one or both groups is ______ and the population standard deviation is ___________.

Suppose you used a 9-point rating scale to compare men who had an annual income over $50 000 (Group 1) with men who had an annual income less than or equal to $50 000 (Group 2) on their liking of a new product. If you studied 40 men in Group 1 and they had a mean of 7 and a standard deviation of 2.5, while the 35 men in Group 2 had a mean of 5 and a standard deviation of 1.4, what is the approximate value of using the t-test?

T-tests are useful when more than four groups are analysed.

Suppose a researcher wished to determine whether sales had improved since a recent promotions campaign by comparing the sales averages before and after the campaign to evaluate its effectiveness. Which of the following statistical tests would you suggest?

A brand manager would like to determine if males are more frequent purchasers of the company's product than females. Which of the following statistical tests is appropriate?

A t-test is used when the sample size in both groups is relatively large and the population standard deviation is known.