Question

4. Principal Sanders wants to know if wearing school uniforms will help students improve their math test scores. She decides to conduct an experiment to find out. She chooses two groups of students to test. One group will wear uniforms, the other will not.

Part A. Define the variables and treatment for the experiment. (3 points: 1 point for each correct answer, for a maximum of 3 points)

What is the control variable? Why?


What is the response variable? Why?


What is the treatment for the experiment?


Part B. Identify three extraneous factors for this experiment. (3 points: 1 point for describing each extraneous factor, for a maximum of 3 points)



Part C. Describe how Principal Sanders could use each of the methods below to deal with extraneous factors in the experiment. (6 points: 2 points for correctly describing how each method could be used, for a maximum of 6 points)

Direct control:


Blocking:


Randomization:


Part D. The results of Principal Sanders's experiment show that the students who wore uniforms scored better on their math tests. What must be done before Principal Sanders can draw a valid conclusion that it is better for all math students in the school to wear uniforms? Explain. (3 points)

Answer 1

In an experiment to assess the impact of school uniforms on math test scores, the independent variable is the use of uniforms, the dependent variable is the test scores, and the control variables are any factors kept constant. Extraneous factors include study habits, socio-economic status, and teacher expectations, which can be controlled through direct control, blocking, and randomization. Before generalizing the results, lurking variables, randomization, sample representativeness, and statistical significance must be considered.

Step-by-step explanation:

Part A: Variables and Treatment

In this experiment, the independent variable is whether students wear school uniforms or not, as this is what is being manipulated. The dependent variable, also known as the response variable, is the students' math test scores, since this is the outcome that is being measured to assess the effect of the independent variable. The control variable could be any other variables that are kept constant and not changed during the experiment, such as the difficulty level of the math tests or the teaching methods used, to ensure that any changes in the response variable are due to the treatment. The treatment for the experiment is the wearing of school uniforms by one group of students.

Part B: Extraneous Factors

Three extraneous factors that could affect the results of the experiment could include variability in the students' study habits, differences in socio-economic status which might affect access to educational resources, and the potential impact of teacher expectations or classroom interactions.

Part C: Dealing with Extraneous Factors

Direct control involves controlling extraneous variables as much as possible by keeping them constant. In the context of this experiment, this might involve ensuring that both groups have the same instructional time and resources. Blocking involves organizing participants into groups based on an extraneous variable, such as dividing the students by proficiency level before assigning them to uniform or non-uniform groups. Randomization is used to assign students to the treatment or control groups in such a way that each student has an equal chance of being in either group, which helps to distribute extraneous variables evenly across both groups.

Part D: Drawing Conclusions

Before Principal Sanders can draw a valid conclusion regarding the benefits of school uniforms on math test scores school-wide, she must consider possible lurking variables and whether the experiment was properly randomized and controlled. It is also crucial to ensure that the sample size is representative of the entire student body and that the results are statistically significant. Repeat testing and peer review could also contribute to the validity of her findings.