topic 5 sampling Flashcards
When do we need sampling?
- If not all units mentioned in our research question can be studied, we need “sample”
- Sample is a subset of the units of analysis
- That implies: Studying a smaller set of units with the aim to say something about all units
what does sampling imply
- That implies: Studying a smaller set of units with the aim to say something about all units
Sampling process:
population, Sampling frame, Sample,Interviewed sample, Data
The relationship between sampling frame and sample
sampling
where and what type of errors may occur
between sampling frame and sample, Might be disturbed by sampling error & bias.
what can. occur Between population and sampling frame
might be registration errors (list is incomplete), RECORDING OR REGISTRATING DATA
relationship between sample and interviewed sample
non response, refusals
Non-Response Rate:
The non-response rate is the percentage of selected individuals in a sample who do not participate or provide data in a study. It can introduce bias if non-respondents differ systematically from respondents in ways that affect the study’s results.
Response Rate
INTERVIEWED SAMPLE UP AND SAMPLE SIZE DOWN The response rate is the percentage of selected individuals in a sample who participate and provide data in a study. A higher response rate generally leads to more representative and reliable results. Researchers often aim to maximize response rates to minimize the potential for bias.
TWO TYPES OF SAMPLING
probabibilty and non probab
Probability sampling
If the probability (chance) is known, that a specific unit of the sampling frame is included in the study. The sample is not biased
- Allows for geralizations to larger population
- Sampling Methods:
Simple random Sampling
In simple sampling, every member of the population has an equal chance of being selected for the sample. It’s like drawing names from a hat with no regard for specific characteristics.
Stratified Sampling
In stratified sampling, the population is divided into subgroups or strata based on certain characteristics (e.g., age, gender), and then random samples are taken from each subgroup. This method ensures representation from each subgroup.
Cluster Sampling (or Multi-Stage Cluster Sampling):
In cluster sampling, the population is divided into clusters or groups, often based on geographic regions. A random sample of clusters is selected, and then all individuals within those selected clusters are included in the sample. This method is practical when it’s difficult to reach every individual in the population directly.
Non-probability sampling
not all have the same chance, If the probability (chance) is not known, that a specific unit of the sampling frame is included in the study reflect the population. The sample is probably biased (voreingenommen).
- Does not allow for generalizations to a larger population of units
- Non-probability sampling methods: