Suppose that you work for a company that has just created a

Suppose that you work for a company that has just created a program designed to teach reading to elementary students. Discuss how an experiment could be created to see whether this product is superior to other reading programs. Develop a hypothesis, label the independent and dependent variables, discuss what the experimental and control groups are doing in the study, and decide who (and how many) participants are needed. Be sure to discuss random sampling and random assignment.

Solution

The experiment that could examine if the new reading program is superior would be fairly straightforward. First, you would develop the hypothesis shown below:

H0: There is no difference between the new reading program and the previous/current program.
H1: The new reading program is superior

Next, you would define the dependent and independent variables shown below:

Dependent variables: Student reading ability
Independent variables: Reading program

To test the independent variable, you will need an experimental group and a control group. The experimental group is the group who receives the critical part of the experiment, the treatment. This is the group who will be using the program to learn reading.

But to know if the program has an effect on elementary students, you will also need to compare the results of the experimental group to a control group, a group which doesn\'t receive the critical part of the experiment. In this case, our control group won\'t have access to program.

How will you decide who is in the experimental group and who is in the control group? What about allowing students to choose which group they\'re in? No, that won\'t work. Maybe the some students without accessing program are already better than students who are in experimental group. We can\'t assume the results will be valid.

Okay, so how about picking the experimental group based on a first-come basis? Sorry, choosing to put the first 150 students who come to class in the experimental group is also not random assignment.

Random assignmenmt is the only way to eliminate other variables that could influence your results.

So how do you ensure random assignment? There are a lot of different methods; the only requirement is that every subject has an equal chance to be in the experimental group