This preview shows pages 1–3. Sign up to view the full content.
Chapter 12 Sample surveys
ActivStats:
12
Read:
Chapter 12
X
1
X
2
.
. .
X
n
POPULATION
Population:
the entire group
of individuals or instances
Distribution:
model (e.g.
normal curve N(
μ
,
σ
))
Parameter:
numerical
characteristic of a population
model
μ
population mean
 population standard
deviation
ρ
 correlation
p
 proportion
SAMPLE
Sample:
a subset of a
population
Distribution:
histogram,
dotplot, etc.
Statistic:
a number computed
from data
x
 sample mean
s
 sample standard deviation
r
– sample correlation
p
ˆ

sample proportion
Vocabulary:
Sampling Frame
 a list of individuals from which a sample is
selected
Sampling Variability
 each random sample is different
Sampling Design
 a method of taking a sample
Sample Size
– the number of elements in a sample
This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentIf a goal is to estimate population parameters or
distribution,
a sample should represent
the whole
population and hence the sample individuals should
be selected
at random
, so that each set of the same
size has the same chance of being selected. A
This is the end of the preview. Sign up
to
access the rest of the document.
 Summer '08
 dikong

Click to edit the document details