Research Design and analysis psychology- design a study to test the hypothesis. PLEASE HELP ME

Question

Participants are asked to either run on a treadmill, lift weights, or walk for thirty minutes. Then their blood pressure is measured. Those who ran on the treadmill are hypothesized to have lower blood pressure that those who lift weights or walked.

 

Design a study to test this hypothesis. Including the following in your response. 

 

1. Indicate if the scenario is between subjects or within subjects.

2. Indicate if this is a directional alternative or null hypothesis.

3. Identify the variance (use language of IV and DV if acceptable) and include in the scale of measurement that will be used (NOIR - Nominal, Ordinal, Interval, and Ratio)

4. Describe the data collection technique to be used (naturalistic observation, survey, systematic observation, or archival). Justify your response.

5. Describe the design of the study (case study, experiment, quasi-experiment, or correctional). Justify your response.  

Answer 1

1. Between subjects, as we are comparing two groups of separate subjects. If you measured blood pressure of the exact same group of people before/after a variable, that would be within subject. 

2. Directional alternative, as the researchers are specifically hypothesizing that the students who ran on the treadmill will have a lower blood pressure. A null hypothesis (or non-directional) simply wants to know if a score is higher or lower. 

3. Independent variable is what can be changed, so the running on the treadmill as the experimental variable. The dependent variable is what is measured, so in this case, the level of blood pressure. The nominal scale is simply the group of subjects, the group of subjects on the treadmill, etc. The ordinal scale is any sequencing you can do with the information involved in the experiment. I'm not sure there's one of these specified. It's not like one group does the treadmill first or second. The interval is the measurement of the variable you're studying (i.e., the blood pressure). The ratio scale is the relationship between the interval information, such as how much more the blood pressures differ. 

4. Data collection will most likely be taken through subject interview (survey), health record review (archival), blood pressure monitoring at beginning of study (systematic observation or empirical data), followed by blood pressure monitoring following study. 

5. Without having information on randomization, blindness, control of variables between the groups, I'd have to say this is a quasi-experiment. True experiments require randomization of subjects, and blindness of the subjects to their variable (or better yet double blindness that even the researchers don't now which subject was assigned to what variable). 

 

Hope that helps!