Determining the Sample Plan zSampling - Use of a small number of items in a population to make conclusions about the whole population.

Determining the Sample Plan zSample – A subset of a larger population.

Determining the Sample Plan zSample Frame – Working list of the entire population.

Determining the Sample Plan zPopulation – Any complete group sharing some common set of characteristics.

Determining the Sample Plan zPopulation element – One member of the population.

Determining the Sample Plan zCensus – An investigation of all individual elements in a population.

Types of samples zProbability - Population members have a known chance of being selected into the sample.

Probability Samples zSimple random sampling – Each element in the population has a known and identical chance of being included in the sample.

Probability Samples zSystematic sampling – Starting point is selected by random process and every nth number on the list is selected.

Probability Samples zStratified sampling 1. Researcher chooses strata (subgroups). 2. Subsamples are drawn from within each stratum (subgroup) using simple random or systematic sampling procedure.

Probability Samples zCluster sampling 1. Researcher chooses strata (subgroups). 2. Simple random or systematic sample of subgroups is drawn.

Types of samples zNonprobability - Probability of selecting any specific population element is unknown.

Nonprobability sampling zConvenience sampling – Researcher obtains individuals who are most conveniently available.

Nonprobability sampling zJudgment sampling - Researcher selects sample based on his or her experienced judgment.

Nonprobability sampling zQuota sampling – technique designed to ensure that various subgroups in a population are represented.

Nonprobability sampling zSnowball (referral) sampling – researcher uses referrals to locate rare or hard-to-find populations.

Sample Size Determination Methods Arbitrary Approach

Sample Size Determination Methods Conventional Approach

Sample Size Determination Methods Cost Basis Approach

Sample Size Determination Methods Confidence Interval Approach