Category: Uncategorized

Extra Credit – No Penalty for Trying If a researcher has a nominal/categorical variable like Sport Participated In (Swimming, Basketball, Track, Soccer), what is meant when a researcher creates “dummy variables” to represent this variable?  What is a dummy variable?

What type of hypothesis is the following: VO2 Max is not related to Running speed.

An assumption underling the independent t-test is that the sample sizes are equal.

A researcher was interested in examining the effects of the daily amount of creatine (5 grams, 10 grams, 15 grams, 20 grams) on the 50-yard sprint time of 200 female runners who volunteered for the study. From these 200 participants, 50 participants were randomly assigned to a daily dose of 5 grams of creatine; 50 participants were randomly assigned to a daily dose of 10 grams of creatine; 50 participants were randomly assigned to a daily dose of 15 grams of creatine; and 50 participants were randomly assigned to a daily dose of 20 grams of creatine. After being on the creatine dosage for 2 weeks, each participant’s 50-yard sprint time was measured. If the 50-yard sprint time was measured using an electronic stopwatch and the reliability of the electronic stopwatch was .95, what would be your evaluation of the reliability of the stopwatch?

A researcher was interested in evaluating if there was a relationship between participants’ academic class rank in high school (e.g., 1st, 2nd, 3rd, etc.) and their class rank in College (e.g., 1st, 2nd, 3rd, etc.).  What statistic would you use?

Is it appropriate to calculate a median for ordinal data?

A researcher developed an intervention designed to increase the strength of adults 85 years or older.  The researcher randomly selected 6 older adults, pretested the adults to determine their pre-intervention strength, implemented the strength training program for 10 weeks (1 training session/week), and then posttested them immediately following the last intervention session.  Higher scores represent greater strength. The null hypothesis for this study is:  

5 older adults volunteered for a study interested in determining the strength of older adults. The 5 older adults were asked to do as many pull-ups as they could. The number of pull-ups for the 5 participants is listed below.  The pull-up results (X) were: 5, 2, 2, 7, 9 What is the median number of pullups?

When a researcher is evaluating the external validity of a research design, what is the researcher primarily focusing on?

A researcher developed the following regression equation to predict muscular strength (y) from fat mass (Fat) in undergraduate students.                                                                             predicted y = 1.0 + 0.7 (Fat)                                                                                           R2 = .49                                                                                    In this sample, what is the proportion of the variance in undergraduate students’  muscular strength that is explained by fat mass (Fat)?