The Internal Validity of an Experiment Is Lowered by Experimenter

question 341

Multiple Choice

The internal validity of an experiment is lowered by experimenter expectancy effects because

• A)the behaviour of the experimenter may have caused the participants to respond the way they did
• B)there is a confounding effect and you can't tell whether the independent variable or the dependent variable caused the results
• C)the results of the experiment may have been due to participants' expectations about the treatment they thought they were receiving
• D)the experimenter made a mistake in using a correlational design instead of an experimental design

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Definitions:

Marginal Mean

The mean of the subset of observations that contribute to the marginal total, providing insight into specific group effects within a larger dataset.

Factorial Designs

Experimental designs used to evaluate the effects of two or more factors by varying them simultaneously and systematically.

Interaction Effects

A statistical concept where the effect of one independent variable on the dependent variable differs across the levels of another independent variable.

Independent Variables

Factors in an experiment that are manipulated to determine if they cause a change in the dependent variable.