The following data were collected in an experiment designed to investigate the impact of different positions of the mother on fetal heart rate. Fetal heart rate is measured by ultrasound in beats per minute. The study included 20 women who were assigned to one position and had the fetal heart rate measured in that position. Each woman was between 28-32 weeks gestation. The data are shown below.
|
Back
|
Side
|
Sitting
|
Standing
|
|
20
|
21
|
24
|
26
|
|
24
|
23
|
25
|
25
|
|
26
|
25
|
27
|
28
|
|
21
|
24
|
28
|
29
|
|
19
|
16
|
24
|
25
|
Is there a significant difference in mean fetal heart rates by position? Run the test at a 5% level of significance.
1) Write out the appropriate null hypothesis and the alternative hypothesis;
2) Calculate the test statistic;
3) Give your conclusion including a comparison to alpha or the critical value.