# Final - Theory Flashcards

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1
Q

Unbiased : E(θ) = ?

A

0

2
Q

Biased : E(θ) = ?

A

Not 0

3
Q

What is the variance of a precise measurement?

A

Small variance

4
Q

What is the variance of an unprecise measurement?

A

High variance

5
Q

How does an increase in n affect the confidence interval?

A

Decreases

6
Q

How does a decrease in variance affect the confidence interval?

A

Increases

7
Q

Define the null hypothesis.

A

Absence of difference or a treatment effect

8
Q

What is alpha?

A

The chance of an error that you are willing to accept

9
Q

What is a type I error?

A

Rejecting a true null hypothesis

10
Q

What is the power of the test?

A

The probability to reject a false null hypothesis

11
Q

What is a type II error?

A

Accepting a false hypothesis

12
Q

What are the outcomes in terms of the power of the test and the type II error if there is a small difference between u and u0?

A
• High type II error

- Low power of the test

13
Q

What are the outcomes in terms of the power of the test and the type II error if there is a large difference between u and u0?

A
• Low type II error

- High power of the test

14
Q

What are the outcomes in terms of the power of the test if alpha is low?

A

Low power of the test

15
Q

What are the outcomes in terms of the power of the test if alpha is high?

A

High power of the test

16
Q

What are the outcomes in terms of the power of the test if alpha is the sample size is low and the variance is high?

A

Low power of the test

17
Q

What are the outcomes in terms of the power of the test if alpha is the sample size is high and the variance is low?

A

High power of the test

18
Q

What three factors allow for a higher power of the test?

A
• Larger difference between u1 and u0
• Larger sample size n
• Higher significance level a