DEFINING AND
COLLECTING DATA
STA1510 NOTES BY RUBBIA KHALID
,OBJECTIVES…
• Understanding issues arise when
defining variables
• How to define variable
• How to collect data
• Identify different ways to collect a
sample
• Understand types of survey error
STA1510 NOTES BY RUBBIA KHALID
, Populations vs samples
Population consists of all
Sample is a portion of
the items or individuals
population selected fo
about which you want to
analysis. When you analy
reach conclusion. When
data from sample you
you analyze population you
compute statistics.
compute parameters.
STA1510 NOTES BY RUBBIA KHALID