Question

A study was conducted to determine if the inclusion of a foreign language requirement in high schools may have a positive effect on a students’ performance on standardized English exams. In a random sample of 100 high schools, 50 of which had a foreign language requirement and 50 that did not, it was found that the average score on the English proficiency was 25% higher for the students having a foreign language requirement.

Is this an experiment or an observational study? Explain how you know which one it is.

What is the response and the explanatory variable in the study?

Answer 1

Answer-

This is a controlled experiment. In a controlled experiment, the experiment divides the people or items into groups where some treatments are applied to one of the groups, while the other group does not receive the treatment.

In the above case also, the students are divided into 2 groups of 50 each where 1 group gets to study the foreign language.

The respose variable is the dependent variable which is the average score of english proficiency

The explanatory variable is the independent avriable which is the foreign study requirement