A researcher finds that the temperature of a room (cold, mild) impacts memory; a cold room is associated with worse memory. The researcher also finds that the temperature effect varies by time of year (summer, winter); the temperature effect is greater in the summer than in the winter. The fact that the temperature effect varied by time of year is an example of a .

Interaction effect

Explanation:

Interaction effect is the effect that occurs when two or more independent variables get interacted with one dependent variable at-least for producing joint effect.This effect result in more than or less tan sum of parts accordingly.

According to the question, example of interaction effect is displayed through producing more amount of impact on memory as compared to winter when memory is impacted by time and temperature gets combined as per variation.

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