Chapter 7 Flashcards
What is Population?
All units possessing the attributes or characteristics in which the researcher is interested
What is Sample?
A subset of a population used to gather data in order to make generalizations
What is Representative sampling?
Sample that accurately reflects characteristics of the population from which it is drawn (if you fail in this step, you fail)
If the sample isn’t representative, it is biased. Be careful about using convenient samples, remember the need to make generalizations
What is a sample size?
Number of people from whom or which data are collected.
Depends on population size
Depends on sampling error you are comfortable with.
What is sampling error?
Degree to which a sample differs from population characteristics.
The larger the proportion of the population size, the amount of sampling error is reduced 5%
What is confidence level?
Degree of accuracy in predicting the result for the population from the result of the sample?
Accuracy in the ability to generalize from sample to population 95-90
What is Random Sampling?
Selection such that each person in the population has an equal chance of being selected
What is non random sampling?
What you do in 499
Work with the population that is available to you!
What is a simple random sample?
Equal chance of being selected
Assign a number and use a random number generator, or draw names from a hat
What is stratified random sampling?
Divide into subgroups and then use a simple random sample from each subgroup (known proportions)
What is cluster sampling?
Identify population by groups, then use a simple random sample (visitors to lax, major tourist spots, random choose two location, survey every 4th visitor)
What is Convenience Sampling?
Selecting from the population available to you (inclusion/exclusion criteria or volunteer.)
What is snowball/network sampling?
Subjects refer you to other subjects
What is purposive sampling?
Highly specialized criteria.
Sample is hand selected by the researcher (499 sampling b or better only serious students)
What is Quota Sampling?
Identify known proportions and then use convenience sampling (25 fresh, 25 soph)
