A researcher administered a math test to a group of 9th graders in September.During the school year these students received an intensive program designed to improve their math skills.In May the math test was again given to these students and their math scores improved.A major problem in this research is that the researcher failed to control for:
A)history.
B)maturation.
C)testing.
D)selection biases.
E)all of these choices.

Question

Quizplus · Accepted Answer

All of these factors could have influenced the results of the study. History, such as changes in the school curriculum or the general societal attitude towards math education, could have affected the students' scores. Maturation, or natural developmental changes, could have influenced their abilities over time regardless of the intervention. Testing could have caused the students to become more familiar with the format or content of the test, which could have inflated their scores. Selection biases, such as non-random assignment to the intervention group, could have influenced the composition of the groups and affected the results.

A Researcher Administered a Math Test to a Group of 9th