Answer to Question #151033 in Statistics and Probability for Randal Rodriguez

Question

5) In an experimental group of 250 individuals, half were given regular doses of aspirin while the other half were given placebos with no effects. Test the claim that the aspirin group has a significantly lower heart attack rate than the placebo group.

Answer 1

we test the hypotheses as follows;

H₀: The mean heart attack rate is equal in aspirin group and in the placebo group.

H₁: The mean heart attack rate in aspirin group is lower than that in the placebo group.

calculate the test statistic using the formula below;

$t_c=\frac{(\bar x_A-\bar x_B)}{SE(\bar x_A-\bar x_B)}$

check the t value from the table; with n-2 degrees of freedom.

if the t-calculated value is greater than the table value, we reject our null hypothesis in favor of the alternative hypothesis.