Question

Directions: identify the test tool use in a certain problem

1. Hospital Infections A medical investigation claims that the average number of infections per week at a hospital in south-western Pennsylvania is 16.3. A random sample of 10 weeks had a mean number of 17.7 infections. The sample standard deviation is 1.8. Is there enough evidence to reject the investigator's claim at alpha = 0.05 ?

Type of test:

Reason/s:

Answer 1

This is a one-sample t-test.

$H_0: \mu=16.3$

$H_1: \mu \not=16.3$

Test statistic: $t=\frac{17.7-16.3}{1.8/\sqrt{10}}=2.46$

P-value: p=2P(T>2.46)=0.0362.

Since the p-value is less than 0.05, reject the null hypothesis.

There is enough evidence to reject the investigator’s claim at α = 0.05.