Question

In: Statistics and Probability

QUESTION 1: You are testing H0: µ = 0 against Ha: µ > 0 based on...

QUESTION 1:

You are testing H₀: µ = 0 against H_a: µ > 0 based on an SRS of 16 observations from a Normal population.

What values of the t statistic are statistically significant at the a = 0.005 level?

t < - 3.286 or t > 3.286

t > 2.947

t < - 3.252 or t > 3.252

QUESTION 2:

A study of commuting times reports the travel times to work of a random sample of 22 employed adults in Chicago. The mean is x¯¯¯x¯ = 33.33 minutes and the standard deviation is s = 25.89 minutes.

What is the standard error (±0.0001) of the mean?

Expert Solution

Question 1:

For testing H₀: µ = 0 against H_a: µ > 0

This corresponds to right hand tail test.

we have, n = 16

df = 16 -1 = 15

And = 0.005

Using t-table, the critical value corresponding to df =15 for = 0.005 is t_c = 2.947

Since, t statistic is statistically significant at the a = 0.005 level

t > t_c i.e. t > 2.947

Answer : t > 2.947

Question 2:

We have

The standard error of the mean is given by

orchestra answered 2 years ago

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