In: Statistics and Probability
Systolic blood pressure was measured on 30 female diabetics between the ages of 30 and 34 from a particular ethnic group. Of interest is whether blood pressure, on average, of women in this population differs from the expected 131 mmHg. The data are available in the file bp.csv.
bp.csv
124 |
128 |
150 |
132 |
133 |
152 |
137 |
116 |
123 |
126 |
146 |
135 |
136 |
132 |
124 |
152 |
137 |
107 |
139 |
125 |
118 |
128 |
119 |
122 |
123 |
111 |
141 |
133 |
117 |
146 |
a. What are the null and alternative hypotheses?
b. (1 mark) What is the value of the test statistic?
c. (1 mark) What is the distribution of the test statistic if the null hypothesis is true?
d. (1 mark) What is the p-value?
e. Using a significance level of ??=0.05, state your conclusions in the language of the problem.
f. Name the two key unstated assumptions required for the validity of your hypothesis test and explain why they are reasonable in this context.
Following table shows the calculations for mean and SD of data:
X | (X-mean)^2 | |
124 | 40.96 | |
128 | 5.76 | |
150 | 384.16 | |
132 | 2.56 | |
133 | 6.76 | |
152 | 466.56 | |
137 | 43.56 | |
116 | 207.36 | |
123 | 54.76 | |
126 | 19.36 | |
146 | 243.36 | |
135 | 21.16 | |
136 | 31.36 | |
132 | 2.56 | |
124 | 40.96 | |
152 | 466.56 | |
137 | 43.56 | |
107 | 547.56 | |
139 | 73.96 | |
125 | 29.16 | |
118 | 153.76 | |
128 | 5.76 | |
119 | 129.96 | |
122 | 70.56 | |
123 | 54.76 | |
111 | 376.36 | |
141 | 112.36 | |
133 | 6.76 | |
117 | 179.56 | |
146 | 243.36 | |
Total | 3912 | 4065.2 |
----------------------------
Conclusion: We cannot conclude that blood pressure, on average, of women in this population differs from the expected 131 mmHg.
(f)
Population should be normally distributed, And observations should be independent from other.
Since sample size is large so normality can be assumed. And it is reasonable to assume that observations are independent.