Given that in an investigation of pregnancy-induced hypertension, one group of women with this disorder was treated with low-dose aspirin, and a second group was given a placebo. A sample consisting of 50 women who received aspirin has mean arterial blood pressure 120mmHg and standard deviation 10mmHg; a sample of 42 women who were given the placebo has mean blood pressure 115mmHg and standard deviation 12mmHg.

Population variances are equal

$H_0: \bar x = \bar y\\H_a: \bar x \neq \bar y$

(two tailed test at 5% significance level)

Here x denotes group I and Y group II

N Mean StDev SE Mean

Sample 1 50 120 10 1.4142

Sample 2 42 115 12 1.8516

Pooled std deviation = 10.9565

df=80

Mean difference= 5

Test statistic t = mean diff/std error = $\frac{5}{2.3299}$ =2.1803

p value = 0.0318

since p <0.05 we reject H0

b) We find p >0.01 hence at 1% significance level we accept H0

This implies that 99% confidence interval contains mean difference =0

4 0

4 years ago

What are the dimensions of the matrix?

dusya [7]

The dimension of a matrix is the no of rows by the no of columns.

Here there are two rows and five column. So the dimensions of the matrix is 2 x 5

6 0

4 years ago