While studying rates of language acquisition for new Canadians from different countries,Curtis Cunning's research assistants informed him that 7 of the 65 subjects had quit and walked out before the study was completed.What type of threat to internal validity does Curtis' experiment have?
A)Selection bias
B)History effect
C)Experimental mortality
D)Maturation
E)Testing effect

Question

Quizplus · Accepted Answer

Experimental mortality refers to the loss of participants before the end of a study. The 7 subjects who quit and walked out before the study was completed represent a form of experimental mortality and could potentially threaten the internal validity of the study. Selection bias refers to a situation where the groups being compared are not equivalent at the start of the study. History effect refers to a situation where external events influence the outcome of a study. Maturation refers to changes in the participants themselves over time that may affect the outcome of a study. Testing effect refers to the potential for participants to perform better on later tests due to practice or familiarity with the testing process. None of these seem to be applicable to this scenario.

While Studying Rates of Language Acquisition for New Canadians from Different