Smapling

Question 1

What are the two broad categories of sampling?

Answer 1

Probability Sampling
- uses a mathematically random process so that each sampling element in the population will have an equal probability of being selected

Nonprobability Sampling
- using something other than a mathematically random process.
- in-depth understanding of some phenomenon
- Not representative

Question 2

What are the 5 types of nonprobability sampling?

Answer 2

Haphazard Sampling
- Researcher selects anyone they come across
- Problematic

Quota Sampling
- Researchers identify general categories into which people will be selected

Purposive Sampling
- identify particular types of cases for in-depth investigation
- (specific kind) Deviant case sampling
- Researcher seeks cases that differ from the dominant pattern or that differ from the predominant characteristics of other cases

Snowball sampling
- Method for identifying and sampling the cases in a network

Sequential Sampling
- Gather cases until no new information is discovered or the diversity of cases is filled

Question 3

Examples of Probability Sampling

Answer 3

Simple random sampling
- uses a sampling frame
- Uses a pure random process to select cases

Systematic Sampling
- Researcher selects every kth case in the sampling frame using a sampling interval

Stratified Sampling
- When a researcher wants to ensure a particular subpopulation is represented in the sample
- Reduce error

Cluster Sampling
- researcher samples a dispersed population and mitigates the high cost to reach a sampled element

Random Didgit dialing
- Does not use a telephone directory as the sampling frame
- Uses all possible telephone numbers as a sampling frame

Question 4

Statistics vs Parameter

Answer 4

Statistics - A numeric estimate

Parameter - Exact characteristics of a population

Question 5

What is Random Sampling

Answer 5

• Each element in the population has an equal chance of selection
• Does not refer to something unexpected

Question 6

What is a Sampling Frame?

Answer 6

Sampling Frame
- A list of all cases in a population
- Always have some degree of inaccuracy

Question 7

What is the sampling ratio?

Answer 7

• The ratio of the size of the sample compared to the size of the target population

Question 8

What are inferential statistics?

Answer 8

A branch of statistics based on a random sample

Without a random sample, you can not infer a larger population