Exam 7: T Tests and Analysis of Variance

When do researchers use t distributions and the family of t tests to seek support for a relationship between variables rather than simply computing confidence intervals based on the normal distribution (as described in Chapter 5)?

A social worker wishes to examine the effectiveness of an innovative method for the treatment of people with a diagnosis of pedophilia. She suspects that it may improve symptoms among some clients, but may make them worse among others. However, she would like to learn if the intervention makes a statistically significant difference in client behaviors. What statistical test should she use?

The two sample dependent t test should be used when two samples consist of the same people or objects measured "before" and "after" some event occurs, or when two samples consist of

If the problem being addressed (the dependent variable) in the previous question can be measured at only the ordinal level, what would be an appropriate statistical test to use?

Using a measurement scale believed to produce interval level measurement, an instructor wishes to learn if the variable "attitude toward statistics" will show improvement over the course of a semester in her class. She administers the scale the first and last days of the class and compares the pairs of scores for every student. What test should she use to learn if there is statistical support for her hypothesis that students will show improved attitudes following her course?

The parametric test designed to examine the relationship among one dichotomous independent variable and a set of interval or ratio level dependent variables is:

Which statistical test is sometimes used to determine if a research sample is sufficiently representative in relation to some potentially confounding variable?

Simple ANOVA is described as "an omnibus test." What does this mean?

The independent t test is often well-suited for comparing the effectiveness of two methods of treatment intervention for addressing some problem such as substance abuse because:

Two sample t tests are designed to learn if there is support for a relationship between variables when:

If the instructor in the previous question had wished to learn instead whether there was a statistically significant difference in attitudes toward statisics among the three sections of the course that she teaches following completion of it, what statistical test should she use?

The non-parametric test that requires at least ordinal level data and that examines the entire distribution of a variable within two samples (and identifies the point at which the two samples differ the most) is:

A non-parametric alternative to the one sample t test is:

The degrees of freedom for the one sample t test are:

Multifactor ANOVA is appropriate for use when there are: