In: Statistics and Probability
A newspaper published an article about a study in which researchers subjected laboratory gloves to stress. Among 225 vinyl? gloves, 60?% leaked viruses. Among 225 latex? gloves, 9?% leaked viruses. Using the accompanying display of the technology? results, and using a 0.05 significance? level, test the claim that vinyl gloves have a greater virus leak rate than latex gloves. Let vinyl gloves be population 1.
Technology Results:::
Pooled? proportion: 0.35
Test? statistic, z: 11.2921
Critical? z: 1.6449
?P-value: 0.0000
90?% Confidence? interval:
0.4441890 < p1? p2 <0.5691444
A) What are the null and alternative hypotheses?
B) Identify the test statistic
C) Identify the P-value
D) What is the conclusion for the test?
Let vinyl gloves be population 1 and latex gloves be population 2.
Let n1 = sample size of population 1 = 225
n2 = sample size of population 2 =225
p1 = sample proportion of virus leak among population 1 = 0.6
p2 = sample proportion of virus leak among population 2 = 0.09
A)
Now we have to test the claim that vinyl gloves have a greater virus leak rate than latex gloves.
That means we have to test that the proportion of virus leak among population 1 is greater than the proportion of virus leak among the population 2. Therefore, the hypothesis is,
B)
Now, the test statistic for testing the above hypothesis is,
where, p1 = sample proportion of population 1, p2 = sample proportion of population 2,
Therefore, the pooled proportion P is,
And the test statistic is,
c)
Now the p-value is
p-value = P(Z>11.3411) = 0.0000
D)
Level of significance = 0.05
Since p-value < level of significance, therefore we reject the null hypothesis H0 and conclude that there is evidence that vinyl gloves have a greater virus leak rate than latex gloves at 5% level of significance.