Question

In: Statistics and Probability

A medical doctor wishes to test the claim that the standard deviation of the systolic blood...

A medical doctor wishes to test the claim that the standard deviation of the systolic blood pressure of deep sea divers is greater than 450. To do so, she selected a random sample of 25 divers and found s = 468.

Assuming that the systolic blood pressures of deep sea divers are normally distributed, if the doctor wanted to test her research hypothesis at the .01 level of significance, what is the critical value?

Place your answer, rounded to 3 decimal places, in the blank. For example, 34.567 would be a legitimate entry.

Expert Solution

Solution:

Given: A medical doctor wishes to test the claim that the standard deviation of the systolic blood pressure of deep sea divers is greater than 450.

That is: we have to test

Sample size =n = 25

Sample standard deviation = s = 468

Level of significance =

We have to find: the critical value.

We use Chi-square test of variance to test the significance of standard deviation.

Thus we use Chi-square critical value table to find critical value.

df = n - 1 = 25 -1 = 24

Look in Chi-square table for df = 24 and level of significance = 0.01 and find critical value.

From above table, for df = 24 and level of significance = 0.01, Chi-square critical value = 42.980

orchestra answered 2 years ago

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