Because students at private high schools get better test scores,on average,than those in public schools,a researcher concludes that the private high schools provide a better education.What is a major weakness of this study,from a scientific standpoint?
A)Students were not randomly assigned to groups.
B)Public high schools tend to be larger than private high schools.
C)Private high schools are more expensive than public high schools.
D)Many students prefer public schools, because they have friends there.

Question

Because students at private high schools get better test scores,on average,than those in public schools,a researcher concludes that the private high schools provide a better education.What is a major weakness of this study,from a scientific standpoint?​
A)Students were not randomly assigned to groups.
B)​Public high schools tend to be larger than private high schools.
C)​Private high schools are more expensive than public high schools.
D)​Many students prefer public schools, because they have friends there.

Quizplus · Accepted Answer

The major weakness of this study is that students were not randomly assigned to groups. This means that there could be other factors that are contributing to the better test scores of students in private high schools, such as the socioeconomic status of the students or the quality of the teachers. Randomization would help to ensure that any differences in test scores between the two groups are solely due to the type of school attended. The other choices are not relevant weaknesses of the study.

Because Students at Private High Schools Get Better Test Scores,on