SAS 10 Flashcards
(41 cards)
two types of data
primary data
secondary daya
are data collected directly by the researcher himself. These are first-hand original sources. data collection can be more effective and informative if given the necessary preparation and planning.
primary data
are information taken from published or unpublished materials previously gathered by other researchers or agencies such as books, newspapers, magazine, journals, published and unpublished thesis and dissertations.
secondary data
one of the most important parts of the research work that needs preparation and planning is choosing the right and appropriate sampling method
sampling techniques
two types of sampling technique
probability sampling
non-probability sampling
every unit has a chance of being selected and that chance can be quantified.
probability sampling
involves the selection of a sample from a population based on the principle of randomization or chance It is more complex, more time consuming and usually more costly than non- probability sampling.
probability sampling
every item in the population does not have an equal chances of being selected and the results are often biased.
non-probability sampling
types of probability sampling
simple random sampling
systematic random sampling
stratified random sampling
cluster random sampling
types of non-probability sampling
convenience sampling
snowball sampling/ respondent-driven sampling
voluntary sampling
is commonly recommended to prevent the possibility of bias or erroneous inference
simple random sampling
each member of the population has an equal chance to be included in the sample gathered
simple random sampling
2 ways can be done through simple random sampling
table of random numbers
lottery or fishbowl technique
write the name of each subject on small slips of paper and deposit them in a box. After they have been thoroughly mixed, the first pick is made followed by other until the chosen size is chosen.
lottery/fishbowl technique
2 ways using lottery fishbowl technique
sampling without placement
sampling with placement
in which the drawn papers are no longer returned in the container
sampling without placement
involves returning to the container every piece of paper drawn
sampling with placement
every nth individual or item in the population is selected, starting with a randomly chosen starting point.
systematic random sampling
This method is useful when the population is ordered, such as in a list or a production line.
systematic random sampling
Select sample at regular intervals based on sampling fraction
• The items or individuals are arranged in some way- perhaps alphabetically or other sort
systematic random sampling
the population is divided into non-overlapping strata or groups based on specific characteristics (e.g., age, gender, income level).
stratified random sampling
A random sample is then drawn from each stratum, ensuring that each group is proportionally represented in the sample.
stratified random sampling
Select random samples from within homogenous subgroups (strata)
• The strata are homogenous as possible and at the same time each stratum is different from one another as much as possible
stratified random sampling
the population is divided into naturally occurring groups or clusters.
cluster random sampling