Question

In spring 2014, faculty from the City University of New York (CUNY) reported on a randomized controlled trial they conducted. The goal of the experiment was to determine whether community college students who assess into elementary algebra could be successful if they were placed directly into college-level statistics (with extra support). The experiment was conducted at three urban CUNY community colleges. At the time of their recruitment into the experiment, participants did not plan to major in a subject requiring college algebra. Students who assessed into elementary algebra and agreed to participate in the study were randomly assigned to one of three treatments: 1) traditional elementary algebra, 2) traditional elementary algebra with extra support in a weekly workshop, or 3) college-level statistics with extra support in a weekly workshop. To control for teacher effects, each faculty member in the study taught one section associated with each of the 3 treatments. All of the instructors were full-time math faculty, and at each of the three colleges, there were four sections of each treatment for a total of 36 sections across the colleges with 721 student participants. In a comparison of course pass rates (C or better), students placed directly into college-level statistics outperformed both elementary algebra treatment groups.

What is the explanatory variable? what is the response variable? what is the confounding variable? is this an experiment or an observational study?

Answer 1

A) explanatory variable is "The extra support given by faculties"

B) the response variable is;

"How successful students who were placed directly into college - level statistics were able to outperform both elementary algebra treatment groups."

C) Confounding Variable is "ability of students to be successful or pass"

D) Experiment

Explanation:

A) An explanatory variable is simply a type of independent variable used to explain the changes that occur in another variable. Furthermore, it can be manipulated by the researcher and is also used to predict differences in the response variable.

Now, from the question, we see that the variable "extra support by the faculties" is used to determine how successful community college students who were placed directly into college - level statistics were in outperforming both elementary algebra treatment groups.

Thus, the explanatory variable is "The extra support given by faculties"

B) In answer A above, we saw that the explanatory variable is used to predict the response variable.

We saw that the explanatory variable predicted how successful community college students who were placed directly into college - level statistics were in outperforming both elementary algebra treatment groups.

Thus, the response variable is;

"How successful students who were placed directly into college - level statistics were able to outperform both elementary algebra treatment groups."

C) A confounding variable is one that influences or changes the effect of the dependent & independent variable. It is therefore used to influence the result/outcome of an experiment/research.

From the question, it's clear that the ability of the students to pass or be successful is what influences the effect of the support by the faculties.

Thus, the Confounding Variable is "ability of students to be successful or pass"

D) The question portrays an experiment because it is being used to check if an hypothesis statement is true or false.