Inferential Statistical Tests

Question 1

Nonparametric tests are used for ______________ and _____________ data, while Parametric tests are preferable for __________________ and ________________ data.

Answer 1

• Nominal and Ordinal
• Interval and Ratio

Question 2

Both Parametric and Nonparametric tests assume that observations are ___________________, which means that a subject’s participation in the study or performance on the DV is not affected by or related to the participation or performance of any other subject.

Answer 2

Independent.

Question 3

____________________ tests (e.g., T-test, ANOVA) are used to evaluate hypotheses about population means, variances, and other parameters.

Answer 3

Parametric tests.

Question 4

Two assumptions of Parametric tests are:

• That the value of interest is ____________________ in the population
• When a study includes more than one group, there is _____________________ - that is, the variances of the populations that the different groups represent are equal.

However, Parametric tests are still rather robust with regard to violation of their assumptions.

Answer 4

• Normally distributed
• Homoscedasticity

Question 5

The most effective way to maximize the robustness of a parametric test is to have an _________________ of subjects in each group; robustness is also increased by having a ______________ sample size and setting alpha at a __________ level.

Answer 5

• Equal number
• Large
• Lower

Question 6

_____________________ are used to analyze data collected on variables that have been measured on a nominal or ordinal scale, and are referred to as “distribution-free” tests. They are used to evaluate hypotheses about the shape of a distribution rather than the distribution’s mean, variance, or other parameter. They are less powerful than Parametric tests.

Answer 6

Nonparametric.

Question 7

The magnitude of the critical value (which divides the sampling distribution into rejection and retention regions) is determined by _____________ and the ___________________.

Answer 7

• Alpha
• Degrees of Freedom

Question 8

____________________ are the number of values or categories in a distribution that are “free to vary” given that certain values or categories are known or fixed.

Answer 8

Degrees of Freedom.

Question 9

The method used to calculate the DF depends on the statistical test; for the t-test for a single sample, the sampling distribution is based on the sample size, and the degrees of freedom are derived from the total number of subjects (__ - __). When using a single-sample Chi-square test, the sampling distribution is based on the number of categories (levels) of the variable, and the DF are derived from the total number of categories (__ - __).

Answer 9

• (N - 1)
• (C - 1)