7 sampling and pilot + case study

whats target population and its difference with sample?

group of individuals that researchers is interested in studying in - its a subset of general pop

however since TP is too large RS takes a sample which means a group of people taking part of research from the TP

what are the 5 sampling techniques

opportunity

volunteer

stratifified

random

systematic

describe opportunity sampling

is where a RSer decides to select whoever is available in a given location at a given time

describe random sampling, and how

all members of the target population have an equal chance of being selected (be all registered, names assigned to a number, use a random number generator

describe systematic sampling

method of where every nth person of the target population is selected (every 2nd person)

describe volunteer sampling

where ptps self-select by responding to an advert placed by researcher

describe stratified sampling

where RSer divides the target population into layers ‘or strata’ dependent on social characteristics that are important for the RSer, then the RSer randomly selects from each layer of the strata - makes it proportional to target pop

ao3 opportunity sampling

+ convenient as it saves time, effort and less costly than random or stratified

- likely to be unrepresentative to TP as its drawn from one street or area, leads to researcher bias

ao3 random sampling

+ free from researcher bias as randomly selection

- time consuming therefore costly to conduct

- may not be representative of all social groups

ao3 systematic sampling

+ reduces researcher bias

therefore more representative than opportunity and less time consuming than random

- lack of true randomness, make it more vulnerable to hidden patterns reducing reliability

ao3 volunteer

+ help find niche or unusual samples

+ creating sample can be cheap for RSer

- volunteers tend to be keen enthusiastic which makes them more susceptible to demand characteristics

- makes it a biased sample, so may not be generalisable

stratified sampling ao3

+ avoids RSer bias, as target pop are randomly selected within these strata

+ representative sample as it reflects the pop making it generalisable

- requires detailed knowledge of pop characteristics

- time consuming dividing them into strata and randomly selecting from each

- Researchers must choose which strata to use, so some social groups may be ignored, leading to an unrepresentative sample.

describe a pilot study

small scale trial of the larger inv in order to identify problems abd decide on modifications to improve the procedure in time for the larger scale versions

pilot study ao3

+ able to iron out any problems before a larger inv. saves money and well designed and fit for purpose

- delay the study and add costs

whats a case study

RSer gathers in depth information on an individual or single event. this leads to rich detailed data that has high validity - qual

ao3 case study

+ rich detail and provide greater depth of understanding

+ rare cases dont allow for larger sample

+ useful for theory contradiction- shine a light on areas for larger scale studies

- not representative as its only one person

- researcher bias as RSer method of reporting can make findings suspect

- reliance on memory