sampling - Sampling Process of selecting observations for...

Sampling – Process of selecting observations for study
A. Sampling terms
1. Population – The entire set of individuals or other entities to which study findings are
to be generalized
2. Sampling frame – List of all elements in a population
3. Sample – Subset of a population used to study the population as a whole
4. Element – Units that comprise the population
(e.g., individuals, households)
5. Parameter – a characteristic of the population, sampling frame, or sample
(e.g., 53% female)
B. Goals of Sampling
1. Representativeness – sample characteristics reflect population characteristics
2. Negotiate tension between feasibility vs. generalizability
We want our samples to be generalizable to broad populations, but we are limited
in our resources
C. Probability Sampling
1. Draws on probability theory
a. A sample randomly drawn will increasingly represent the population as the sample size
increases.
b. Probability theory rests on the assumption of
EPSEM - Equal probability of selection method
c. By relying on random samples, we can assume that the sample parameters will
increasingly mirror the parameters of the true population as sample size increases
2. Sampling error (or sample selection bias)
a. Extent to which the sample distribution does not reflect the population distribution.