Page 268 - Area 9 - Relevant Document

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Produces larger error

Expensive

2. Systematic sampling- selects every kith elements in the
population for the sample with the starting point determined at
random the first kith element. Applicable to heterogeneous
population.
Steps:

A. Make a population frame
B. Determine the sample size at least 25% of the
population
C. Compute the sampling interval, K = n/N where n is the
sample size and N is the population.
D. Determine the random start r where r ranges from one
to k.
E. Choose the specific n using simple random sampling as
the first sample. Succeeding samples will be r + k, r +
k2, r + k3 and so on until the desired number of elements
in the sample is met.
3. Stratified sampling method- applicable to heterogeneous
population. The population is divided into strata from which
random samples are taken.
4. Cluster sampling- applicable to heterogeneous population.
Sample is obtained by successive sampling of units, sets and
subsets.

B. Non-probability Sampling

1. Quota sampling- some information on the characteristics of the
population are used to select sample members that
representative or typical, and suitable for research purposes.
2. Purposive sampling- characterized by the used of judgment and a
deliberate effort to obtain representative sample by including
presumably typical areas or group in the samples.

Measure of Central Tendency or Location

1. Arithmetic Mean – arithmetic mean or simply mean of a set of N
numbers X1, X2, X3 ……Xn is defined by

Mean = X1+ X2+ X3+ ……Xn