STATS END TERM EXAM Flashcards
is selected from the population and the data gathered from it will represent the data that can be gathered from the entire population.
sample
is concerned with the selection of a subset of population that will be used to estimate the characteristics of the entire population.
Sampling technique
is a statistical error that occurs when an analyst does not select a sample that represents the entire population of data. As a result, the results found in the sample do not represent the results that would be obtained from the entire population
Sampling Errors
TYPES OF SAMPLING ERRORS
Population-Specific Error
Selection Error
Sample Frame Error
Non-response Error
occurs when a researcher understands who to survey.
Population-Specific Error
occurs when the survey is self directed, or when only those participants who are interested in the survey respond to the questions. Researchers can attempt to overcome selection error by finding ways to encourage participation.
Selection Error
occurs when a sample is selected from the wrong population data
Sample Frame Error
occurs when a useful response is not obtained from the surveys because researchers were unable to contact potential respondents (or potential respondents refused to respond).
Non-response Error
SLOVINβs FORMULA
π = π / 1 + ππ 2
TYPES OF SAMPLING TECHNIQUES
Probability Sampling
Non-Probability Sampling
it is a sampling procedure where every element of a population is given an equal chance of being selected as a member of a sample.
Probability Sampling
This is a sampling procedure in which an element of the population is not given an equal chance of selected sample.
Non-Probability Sampling
TYPES OF PROBABILITY SAMPLING
Simple Random Sampling
Systematic Sampling
Stratified Sampling
Cluster Sampling
- This is the most basic sampling technique
- It is a sampling technique in which every element of the population has the same probability of being selected for inclusion in the sample.
Simple Random Sampling
- Is another type of probability sampling which is also known as interval sampling.
Systematic Sampling
- This method considers an interval in selecting a sample from a given population.
Systematic Sampling
- Is a random sampling technique in which a list of elements of the population is used as a sampling frame and the elements to be included in the desired sample are selected by skipping through the list at regular intervals.
Systematic Sampling
- Is a random sampling method that divides a population into different homogeneous subgroups called strata. Random samples will be selected from each stratum so that the population will be well presented. We use stratified random sampling when we consider subgroups like year level of students, gender and age, among others.
Stratified Sampling
- Is a random sampling technique in which the population is first divided into strata and then the samples are randomly selected separately from stratum.
Stratified Sampling
is the subset of strata.
Stratum
This type of random sampling is also called area sampling because it is usually used on a geographical basis.
Cluster Sampling
requires a complete list of clusters that represent the sampling frame. Choose a few clusters randomly as a source of primary data and the data that can be collected from each cluster to represent the characteristics of the whole population.
Cluster Sampling
TYPES OF NON-PROBABILITY SAMPLING
Convenience Sampling
Purposive Sampling
Quota Sampling
Snowball Sampling
- Selecting a participant because they are often readily and easily available.
- Tends to be a favored sampling technique among students as it is inexpensive and an easy option compared to other sampling techniques.
- This often helps to overcome many of the limitations associated with research.
- Also known as accidental, opportunity or grab sampling.
Convenience Sampling