Final - Theory Flashcards
Unbiased : E(θ) = ?
0
Biased : E(θ) = ?
Not 0
What is the variance of a precise measurement?
Small variance
What is the variance of an unprecise measurement?
High variance
How does an increase in n affect the confidence interval?
Decreases
How does a decrease in variance affect the confidence interval?
Increases
Define the null hypothesis.
Absence of difference or a treatment effect
What is alpha?
The chance of an error that you are willing to accept
What is a type I error?
Rejecting a true null hypothesis
What is the power of the test?
The probability to reject a false null hypothesis
What is a type II error?
Accepting a false hypothesis
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?
- High type II error
- Low power of the test
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?
- Low type II error
- High power of the test
What are the outcomes in terms of the power of the test if alpha is low?
Low power of the test
What are the outcomes in terms of the power of the test if alpha is high?
High power of the test
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?
Low power of the test
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?
High power of the test
What three factors allow for a higher power of the test?
- Larger difference between u1 and u0
- Larger sample size n
- Higher significance level a
