Question Question 1 of 20 1.0 Points

19 Jun Question Question 1 of 20 1.0 Points

Question
Question 1 of 20 1.0 Points
A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evidence to reject the claim that the lab technician’s accuracy is within the target accuracy?

State the null and alternative hypotheses.

A. H0: s2 ? 1.2, H1: s2 ? 1.2

B. H0: s2 ? 1.2, H1: s2 = 1.2

C. H0: s2 < 1.2, H1: s2 ? 1.2

D. H0: s2 ? 1.2, H1: s2 > 1.2 .

Question 2 of 20 1.0 Points
Smaller p-values indicate more evidence in support of the:

A. alternative hypothesis

B. the reduction of variance

C. quality of the researcher

D. null hypothesis .

Question 3 of 20 1.0 Points
The hypothesis that an analyst is trying to prove is called the:

A. quality of the researcher

B. alternative hypothesis

C. level of significance

D. elective hypothesis .

Question 4 of 20 1.0 Points
A severe storm has an average peak wave height of 16.4 feet for waves hitting the shore. Suppose that a storm is in progress with a severe storm class rating. Let us say that we want to set up a statistical test to see if the wave action (i.e., height) is dying down or getting worse. If you wanted to test the hypothesis that the waves are dying down, what would you use for the alternate hypothesis? Is the P-value area on the left, right, or on both sides of the mean?

A. H1: is not equal to 16.4 feet; the P-value area is on the right of the mean

B. H1: is greater than 16.4 feet; the P-value area is on the left of the mean

C. H1: is greater than 16.4 feet; the P-value area is on both sides of the mean

D. H1: is less than 16.4 feet; the P-value area is on the left of the mean .

Question 5 of 20 1.0 Points
A manufacturer of flashlight batteries took a sample of 13 batteries from a day’s production and used them continuously until they failed to work. The life lengths of the batteries, in hours, until they failed were: 342, 426, 317, 545, 264, 451, 1049, 631, 512, 266, 492, 562, and 298.

At the .05 level of significance, is there evidence to suggest that the mean life length of the batteries produced by this manufacturer is more than 400 hours?

A. No, because the p-value for this test is equal to .1164

B. Yes, because the test value 1.257 is less than the critical value 2.179

C. No, because the test value 1.257 is greater than the critical value 1.115

D. Yes, because the test value 1.257 is less than the critical value 1.782 .

Question 6 of 20 1.0 Points
Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5% level of significance.

What is your conclusion?

A. Cannot determine

B. More seniors are going to college

C. Reject H0. There is enough evidence to support the claim that the proportion of students planning to go to college is now greater than .79.

D. Do not reject H0. There is not enough evidence to support the claim that the proportion of students planning to go to college is greater than .79. .

Question 7 of 20 1.0 Points
In an article appearing in Today’s Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean number of calories per serving to be 78 with a sample standard deviation of 7.

State the null and alternative hypotheses.

A. H0: 75, H1: < 75

B. H0: = 75, H1: > 75

C. H0: = 75, H1: ? 75

D. H0: 75, H1: > 75 .

Question 8 of 20 1.0 Points
A type I error occurs when the:

A. null hypothesis is incorrectly rejected when it is true

B. sample mean differs from the population mean

C. null hypothesis is incorrectly accepted when it is false

D. test is biased .

Question 9 of 20 1.0 Points
The form of the alternative hypothesis can be:

A. neither one nor two-tailed

B. one-tailed

C. one or two-tailed

D. two-tailed .

Question 10 of 20 1.0 Points
A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evidence to reject the claim that the lab technician’s accuracy is within the target accuracy?

At the a = .01 level of significance, what is your conclusion?