Data collection answers research questions, test hypothesis, and helps in drawing conclusions or recommendations based on study.
What are the key factors of data collection?
1.kind of data to be collected
2.methods of data collection
3.scoring of the data
Some part of the larger body specially selected to represent a whole.
Sample
It is the process which, a part is chosen as a representative.
Sampling
What are the reasons for drawing a sample?
It is less costly, less time consuming and less cumbersome.
What are the 2 types of sampling ?
Probability sampling (random sampling)
Non-probability sampling (non-random sampling)
It is the selection based on randomization, random selection or chances.
Units of selection are randomly selected and each unit of selection can be calculated. Thus reliable estimates can be produced and statistical interferences can be made about the population.
Probability sampling
The probability sampling has 4 sub-types.
Simple
Systemic
Stratified
Cluster
Identify the sub-type of probability base on the given statement.
♆ Every individual or item from the frame has an equal chance of being selected.
♆ Selection may be with or, without replacement.
A. Simple
Identify the sub-type of probability base on the given statement.
♆ Random samples are unbiased and, on average, representative of the population.
D. Simple
How to choose using simple random sampling?
1. Assign numbers
2.Raffle or Random Number Generator
Identify the sub-type of probability base on the given statement.
♆ Is the random sampling method that requires selecting samples based on a system of intervals in a numbered population.
A. Systemic
How to choose using systematic random sampling?
1.Confirm the population total.
2.Determine sample size
3.Determine your sampling interval.
4.Select your random starting point.
5.Add your sampling interval until you have the desired sample.
What are the benefits of Systematic Sampling?
1.It provides some control over the process - although it still has an element of randomness, it also introduces some control and process into the selection.
2.It's low risk of chance that the data can be contaminated.- because of the even distribution of members to form samples.
3.It's resistant to bias.- researchers have little control over who gets selected for systematic sampling.
Identify the sub-type of probability base on the given statement.
A probability sampling technique in which the total population is divided into homogenous groups to complete the sampling.
A.Simple
B.Systemic
C.Stratified
D.Cluster
C.Stratified
Stratified random sampling is also known as _____ or ______.
proportional sampling
quota random sampling
homogenous groups or ______
strata
How to choose using stratified random sampling?
1.Define the strata of your sample. (The group which you would want to gather data about.)
2.Determine sample size.
3.Randomly select from each stratum.
4.Combine all stratum samples into representative sample.
Formula for stratified random sampling?
What is the advantage of a stratified random sampling?
It gives a systematic way of gaining a population sample that takes into account the demographic make- up of the population, which leads to a stronger research.
What is the disadvantage of stratified random sampling?
Researcher may hold prior knowledge of the population's shared characteristics beforehand, which increases the risk for selection bias when strata are defined.
Identify the sub-type of probability base on the given statement.
A sampling method where the researcher divides the entire population into separate groups then a random sample of these groups is selected. This method is typically used when the population is large, widely dispersed, and inaccessible.
It should ideally mirror the characteristics of the population as a whole.
A.Simple
B.Systemic
C.Stratified
D.Cluster
D.Cluster
What are the (3) Cluster sampling techniques?
Single-stage sampling
Double-stage sampling
Multistage sampling
A cluster sampling technique where each unit of the chosen cluster is sampled. Researchers will divide the total sample into a predetermined number of clusters based on how large they want each cluster to be.
Then they randomly select and sample from the clusters and collect data from each individual unit in the selected clusters.
Single-stage sampling
A cluster sampling technique where researcher only collect data from a random subsample of individual units within each of the selected clusters to use as the sample.
Double-stage sampling
Double-stage sampling technique is ____ than single-stage sampling and should only be used when it is too challenging or expensive to test the entire cluster.
less precise
This type of cluster sampling involves the same process as double-stage sampling, except with a few extra steps.
Researchers will continue to randomly sample elements within the clusters until they reach a manageable size.
Multi-stage cluster
What are the types of non-probability sampling?
Convenience sampling
Purposive or judgement sampling
Quota sampling
Snowball sampling
A type of non-probability sampling where a few initial samples are taken by SRS. The sample is then expanded thru referrals.
C. Snowball sampling
(Network sampling)
A type of non-probability sampling is like the stratified sampling but without randomization. The population is normally subdivided into subgroups, like gender or year level of students. When the stratification is done, a quota for each stratum is determined.
B. Quota sampling
What are the types of quota sampling?
controlled and uncontrolled sampling
In this method of non-probability sampling respondents are chosen based on the judgement or opinion of the researcher upon the advice of certain experts. This somehow leads to personal biases and the exclusions of the other units from the study.
D. Purposive or judgement sampling
Non-probability sampling which involves using respondents who are convenient to the researcher. There is no pattern whatsoever in acquiring these respondents.
C. Convenience sampling
It is less likely advised as a choice for sampling as it can often produce really wrong answers.
