Give the 36 descriptions of studies in this link (http://psych.athabascau.ca/html/Validity/frames.html) that may or may not have a problem with internal validity. Your task is to determine whether or not the study has a problem. If it does not have a problem, select "this experiment is internally valid." If it does have a problem, select the appropriate threat to internal validity from the provided list.
Out of the 36 descriptions, how accurate were you in identifying whether there was a problem or not? Did this exercise help you in determining if there was a problem? Did the exercise help you in determining what the problem was?
Provided is give you the eight classic "threats" to internal validity to help understand the given question.
Internal validity is exclusively about your causes and effects. It deals with your causes producing false effects. These eight threats all interfere with this basic problem. As you read through the descriptions, check and see which possible threats might harm the research. It can be subtle, but these are basic enough so as to allow you to grasp the threats as they come up.
This is a good summary:
Let's list the basic eight:
1. Confounding: This is a matter of basic causal problems. You are measuring two variables, but the changes in your independent variable might come from other sources than what you are measuring. Say you think that stress leads to paranoia (for example). You are measuring paranoia ONLY by stress. There may be other factors. This is the big one and is always a problem. The simple question: could there be other causes for my results? It's tough to create a study that can solve all these problems. This is where the literature review can come in handy, since you ...
Internal validity tests are examined in the solution. How accurate you were at identifying whether there was a problem or not is determined.