Midterm

Question 1

If a process is operating with only chance causes of variation, what does that mean?

Answer 1

It is in statistical control

Question 2

What are “chance causes of variation”?

Answer 2

Unavoidable causes that result in natural inherent variability
Also known as noise

Question 3

What is type 1 error?

Answer 3

When Ho is true but you reject Ho

Question 4

What is type 2 error?

Answer 4

When Ha is true and you fail to reject Ho

Question 5

What is the relationship between the sample size and confidence interval length?

Answer 5

If sample size is x times larger, the confidence interval will be sqrt(x) times smaller.
New confidence interval length = old confidence interval length/sqrt(x)

Question 6

What is common population variance?

Answer 6

MSE

Question 7

What does increasing the sample size do to power?

Answer 7

Increasing the sample size increases the power

Question 8

What does increasing the alpha value do to the power?

Answer 8

Increasing alpha increases the power

Question 9

What is the estimate of common population mean?

Answer 9

X bar bar,
(Xbar1s1 + … + xbar2s2)/N

Question 10

How to get sp^2 without calculating it?

Answer 10

sp^2 = MSE

Question 11

What is the estimate of common population standard deviation?

Answer 11

Sp = sqrt(MSE)

Question 12

What is the denominator of the ANOVA test statistic?

Answer 12

MSE

Question 13

What is the numerator of the ANOVA test statistic?

Answer 13

MSG

Question 14

What does MSE measure?

Answer 14

variation within individual samples

Question 15

What does MSG measure?

Answer 15

variation between sample means