Age and BMI Researchers in a clinical study collected information from their sub
ID: 3177399 • Letter: A
Question
Age and BMI
Researchers in a clinical study collected information from their subjects at the beginning of the study. Two of the variables were body mass index (BMI) and age. We are interested in seeing if there is an association between these two variables. The data from the study can be found in the file AgeBMI.
(a)
Describe the population slope in the context of the study and assign a symbol to it.
(b)
State the appropriate null and alternative hypotheses in terms of the population slope using the symbol used in part (a).
(c)
Is a theory-based test appropriate? Why or why not?
(d)
Use a theory-based approach to find the p-value.
(e)
Summarize your conclusion based on the p-value reported in part (b).
(f)
If you were testing to determine if there was a positive association between age and BMI, what is the theory-based p-value?
Data:
Explanation / Answer
a. To obtain the regression eqaution, enter data in Minitab-Stat-Regression-Fitted Line plot-enter BMI in Y variable and Age in X variable-click Ok.
The regression eqaution is:
BMI=23.21+0.3012 Age
The slope, beta1=0.3012 can be interpreted as follows:
With increase in age by one year, the BMI is supposed to increase by an amount of 0.3012.
b. The null and alternative hypotheses are as follows:
H0:beta1=0 (age is not useful for predicting BMI)
H1:beta1=/=0 (age is useful for predicting BMI)
c. Theory based test is appropriate, because data has been collected in 39 pairs, (Age, BMI) and regression equation is obtained using the data.
d. Follow the instructions to obtain the p value.
Stat-Regression-Regression-Fit regression model-enter BMI in Response and Age in Continuous predictor-click Ok.
The p value is: 0.071