Descriptive Statistics Flashcards
1
Q
What % of data is within 1 SD of the mean?
A
68%
2
Q
What % of data is within 2 SD of the mean?
A
95%
3
Q
What % of data is within 3 SD of the mean?
A
99%
4
Q
Reliability vs. Validity.
A
Reliability: precise,
Validity: accurate
5
Q
What are the major sources of variability?
A
1) biologic variation (individual)
2) measurement variation (observer)
3) instrument/ analytical error (instrument)
6
Q
What is a Z score?
A
how many SDs above the mean a certain value is in a normal (Gaussian) distribution
