Question

male	1st Systolic	1st Diastolic	2nd Systolic	2nd Diastolic
1	132	74	132	82
2	108	70	108	74
3	124	78	134	78
4	116	42	116	48
5	118	76	116	70
6	128	80	128	80
7	132	90	130	92
8	106	64	110	64
female
1	168	46	156	52
2	198	82	192	84
3	110	74	110	76
4	170	94	168	100
5	142	58	140	52
6	168	52	172	54
7	90	32	82	0

For the above data, test the hypothesis that the first reading and the second reading each are greater than 115 mmHg, with an α of 0.05. (Here, combine men and women into one sample: you should have an N of 15) What test would be most appropriate and why? Is the result significant? State your conclusions.

Answer 1

From above plots we observed that the two sets of data come from normal distribution. Since population variances are unknown so one sample t test is appropriate.

One-Sample T: 1st Systolic, 2nd Systolic

Test of mu = 115 vs > 115

95% Lower
Variable N Mean StDev SE Mean Bound T P
1st Systolic 15 134.00 29.84 7.70 120.43 2.47 0.014
2nd Systolic 15 132.93 28.91 7.47 119.78 2.40 0.015

Since p-values for both readings are less than 0.05 so the results are significant and there is sufficient evidence to conclude that  the first reading and the second reading each are significantly greater than 115 mmHg.