Chp4 Final

Survey Research Constructing Surveys Measuring Responses Important Considerations for Survey Items Collecting Survey Data Evaluating Surveys and Survey Data Sampling Probability Sampling Nonprobability Sampling

What is the relationship of a sample to its population?

Selecting subjects is an important part of any research regardless of its design.  A population consists of all people, animals, or objects that share at least one characteristic.  A sample is a subset of the population of interest (the population we are studying).

Sampling

What are two advantages of probability sampling over nonprobability sampling?

1. A probability sample is more likely to represent the population (external alidity) than a nonprobability sample. !. "e know the exact odds of members of the population being included in our sample. #his tells us whom the sample represents.

Probability Sampling

Which are the main probability sampling methods?

#he four main probability sampling methods are$  simple random sampling

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 systematic random sampling

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 stratified random sampling

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 cluster sampling

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Probability Sampling

%robability Sampling ðods 1. simple random sampling ' the most basic form of probability sampling in which a portion of the whole population is being selected. 2. systematic random sampling- all members of the population are known or can be listed in an unbiased way, a researcher may select eery nth person from the population.

%robability Sampling ðods . stratified random sampling  this is used when the populations is known to contain distinct subgroups. * +s obtained by randomly sampling from people in each subgroup in the same proportions as they exist in the population.

%robability Sampling ðods . cluster sampling  this is used when the population of interest is ery large. * -esearchers sample entire cluster.

Which are the main nonprobability sampling methods?

#he four main nonprobability sampling methods include$  uota sampling

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 conenience sampling

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 purposie sampling

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Nonprobability  snowball sampling Sampling

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Non-probability sampling 1. quota sampling  researchers select samples through predetermined uotas that are intended to reflect the make of the population. 2. convenience sampling ' known also as accidental sampling. 3. purposive sampling- this is used when non' random samples are selected because the indiiduals reflect a specific purpose of the study.

Non-probability sampling

. snowball sampling   this is used when the researcher locates one or a few people who fit the sample criterion and asks these people to locate or lead them to additional indiiduals.