Errors Flashcards
(9 cards)
1
Q
Whats a time series?
A
A serial record in time of a dependent variable
2
Q
Examples of time series? (2)
A
Wave data, meteorological data
3
Q
Standard deviation
A
A measure of spread of a signal about the mean
4
Q
Standard deviation equation
A
Sum of the (difference between each value and the mean)^2 / n-1
5
Q
Standard Error
A
A measure of a spread of the mean if the study is repeated
6
Q
Standard Error equation
A
Standard deviation / square root(n)
7
Q
What’s a moving average?
A
Smooths out short term fluctuations to highlight longer-term trends
8
Q
What’s a weighted average?
A
sum of weighted terms/ n terms
9
Q
Weighted average example
A
25 in a class. 10 got 80%. 15 got 60%. So (10x80)+(15 x 60)/ 25 = 68%
