In Professor John's Three-Week Experiment, the Control Group Has Realized

question 15

Multiple Choice

In Professor John's three-week experiment, the control group has realized that the experimental group is being exposed to lavish lunches as part of the experiment, while they are stuck with plain microwaved meals. In protest, they have decided to stop full participation. Which form of internal invalidity does Professor John have to worry about?

• A)Maturation
• B)Demoralization
• C)Selection biases
• D)Experimental mortality
• E)Statistical regression

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Definitions:

Registered Democrats

People who are officially enrolled as Democratic Party members with voting rights in the United States.

Registered Republicans

Individuals officially registered to vote as members of the Republican Party in the United States.

Pooled Variance T-test

A statistical test that combines the variances of two samples to test the hypothesis that the means of two populations are equal under the assumption of equal variances.

Degrees Of Freedom

The number of independent pieces of information in a dataset available for estimating parameters or calculating a statistic, usually defined as the number of observations minus the number of parameters being estimated.