Ch 3: Characterizing and Displaying Multivariate Data Flashcards
1
Q
density function f(y)
A
the relative frequency of occurrence of the random variable y
2
Q
µ
A
population mean
3
Q
E (y)
A
the expected value of y
4
Q
ȳ
A
sample mean
5
Q
E (ȳ) =
A
µ
6
Q
var (ȳ) =
A
σ2/n
7
Q
E (ay) =
A
aE(y) = aµ
8
Q
Vay (y) =
A
σ2 = E(y - µ)2
9
Q
S2
A
Sample variacne
10
Q
E (S2) =
A
σ2
11
Q
Standard deviation
A
the square root of either the population variance or sample variance
12
Q
Bivariate Random Variable (x, y)
A
if two variables x and y are measured on each research unit (object or subject)
13
Q
population covariance
A
Cov (x, y) = σxy = E[ (x-µx) (y-µy) ]
14
Q
s
A
Sample standard deviation
15
Q
Orthogonal
A
Variables with zero sample covariance
