research methods: sampling techniques/methods

Question 1

what are the 5 types of sampling techniques?

Answer 1

.random
.opportunity
.volunteer
.systematic
.stratified

Question 2

what is meant by random sampling?

Answer 2

.participants have an equal chance of selection .have a list of all people in the population (sampling frame)
.use a lottery method to select names from the list, e.g. pick names from a hat

Question 3

what are the strengths to random sampling?

Answer 3

.potentially unbiased sample, as
-no researcher bias in choice of
participants

Question 4

what are the negatives to random sampling?

Answer 4

.needs a sampling frame which may be hard to access
.selected p’s may refuse to take part/be hard to contact

Question 5

what is meant by opportunity sampling?

Answer 5

.anyone who is willing and able,
who happens to be there at the time, e.g. select people who are on the high street

Question 6

what is a strength to opportunity sampling?

Answer 6

.quicker and easier to carry out since the participants are already available and no sampling frame is needed

Question 7

what is a negative to opportunity sampling?

Answer 7

.likely to be unrepresentative because
-all from one place, e.g. same street
-researcher bias -may pick (and avoid)
certain types of people

Question 8

what is meant by volunteer sampling?

Answer 8

.participants select themselves to be part of the sample
.researcher may place an advertisement where the target population is likely to see it,
e.g. newspaper

Question 9

what is a strength to volunteer sampling?

Answer 9

.ensures participants will be motivated (more so than someone stopped on street)
.convenient for the researcher (‘they come to you’)

Question 10

what is a negative to volunteer sampling?

Answer 10

.unrepresentative -volunteer bias: research may attract a certain ‘profile’, e.g. curious and wants to please researcher, affects generalisation

Question 11

what is meant by systematic sampling?

Answer 11

.gather a sampling frame of the population e.g. school register in alphabetical order
.choose every nth person e.g. every 6th pupil

Question 12

what is a strength to systematic sampling?

Answer 12

.if you list people in order (e.g. by age), you can ensure a diverse sample
.no investigator effects

Question 13

what is a negative to systematic sampling?

Answer 13

.needs a sampling frame
.selected p’s may refuse to take part

Question 14

what is meant by stratified sampling?

Answer 14

.calculate proportions of subgroups (strata) in the population (e.g. 55:45 Male:Female). .randomly select proportionate numbers for your sample, from each subgroup

Question 15

what is a strength to stratified sampling?

Answer 15

.most representative of the population, designed to accurately reflect composition of the population
.no researcher bias in choice of p’s

Question 16

what is a negative to stratified sampling?

Answer 16

.need a detailed sampling frame which
may not be readily available
.selected p’s may refuse to take part