t-test

The p-value was .23 for an independent t-test that compared two means. What does this p-value indicate?

• The two means are different from each other.

• The two means are no different from each other.

• The magnitude of the effect was small.

The independent t-test can be used for outcome variables that are... (select all that apply)

• Interval

• Ratio

• Ordinal

• Nominal

The magnitude of an effect is estimated by the...

• p-value

• 95% confidence interval

• Cohen's d

• Levene's test

The assumption of homoscedasticity is checked by...

• Creating a histogram for the outcome variable

• Creating a histogram for the outcome variable for each predictor category.

• Running a Levene's test

When is it important to take the weighted average of the variances between groups?

• When you have unequal sample (group) sizes

• When you have equal sample (group) sizes

• You can always take the weighted average

True or False. Wider confidence intervals indicate that our results our precise or trustworthy. Narrow confidence intervals suggest our estimates may be inaccurate.

• True

• False