In: Statistics and Probability
The blood pressure measurements of a single patient were taken by twelve different medical students and the results are listed below. Construct a scatterplot, find the value of the linear correlation coefficient r, and find the P-value using
alphaαequals=0.050.05.
Is there sufficient evidence to conclude that there is a linear correlation between systolic measurements and diastolic measurements?
systolic (x) |
137137 |
133133 |
139139 |
120120 |
126126 |
121121 |
128128 |
128128 |
129129 |
143143 |
143143 |
138138 |
|
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
diastolic (y) |
9595 |
9393 |
101101 |
8585 |
8989 |
8080 |
8181 |
8484 |
8080 |
9595 |
105105 |
9797 |
What are the null and alternative hypotheses?
below is scatter plot:
null hypothesis: Ho: ρ | = | 0 | |
Alternate Hypothesis: Ha: ρ | ≠ | 0 |
correlation coefficient r= | Sxy/(√Sxx*Syy) = | 0.851 |
test stat t= | r*(√(n-2)/(1-r2))= | 5.127 |
P value = | 0.0004 |
reject Ho and conclude that there is a linear correlation between systolic measurements and diastolic measurements