Which of the Following Threatens the Internal Validity of an Experiment

question 18

Multiple Choice

Which of the following threatens the internal validity of an experiment?

• A) Using an independent variable with more than one level.
• B) Failing to generalize the results outside the lab.
• C) Failing to assign participants randomly to conditions.
• D) Failing to use a random sample.
• E) Using more than one dependent variable.

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Definitions:

Purpura

A condition characterized by the appearance of purple spots on the skin, resulting from small blood vessels leaking under the skin.

Petechiae

Tiny, round spots appearing on the skin due to bleeding under the skin, often red, purple, or brown in color, and can indicate a range of medical conditions.

Ecchymoses

Discolorations of the skin resulting from bleeding underneath, typically caused by bruising.

Correlational Research

A research method used to determine the relationship between two variables without implying a cause-and-effect relationship.