Biostats Flashcards
1
Q
Chi Square Test
A
Binary data, 4 diff groups
- what is expected for certain box? = row total X column total / grand total
2
Q
If Standard Deviation is 0?
A
All observations are the same
3
Q
What is an ordinal variable?
A
Ranked
4
Q
P < 0.05, what’s the chances a mistake was made?
A
1/20
5
Q
Data before/after with 1 group of participants?
A
Paired t-test
6
Q
2 independent groups, continuous variable?
A
Unpaired t-test (with n-2 degrees of freedom)
7
Q
Confidence Interval equation?
A
CI = X + or - Z (SE)
- 95% CI for mean, then Z = 2 SD’s
- 99% CI for mean, then Z = 3 SD’s
8
Q
Power
A
P = 1 - beta
9
Q
Type I error
A
Alpha: you Abserved a difference that didnt exist (rejected null when it is true)
10
Q
Type II Error
A
Beta: you were Blinded by the truth (failure to reject null when alternative is true)
