SAMPLING

Question 1

what is the population?

Answer 1

the group of people who are the focus of the researcher’s interest - this is what the sample is drawn from

Question 2

what is a sample?

Answer 2

the group that take part in the experiment, drawn from target population and is presumed to be representative of the population being studied

Question 3

RANDOM SAMPLE

Answer 3

all members of the target population have an EQUAL chance of being selected
EG using a lottery method

Question 4

what are pros of a random sample?

Answer 4

free from researcher bias

Question 5

cons of a random sample

Answer 5

difficult and time consuming
could still end up with an unrepresentative sample
selected ppts can just refuse to take part

Question 6

what is a SYSTEMATIC SAMPLE

Answer 6

is when every Nth number of the population is selected

uses a sampling frame - eg target population ordered by alphabet

Question 7

EXPLAIN STRATIFIED SAMPLE

Answer 7

sample reflects the proportions of a certain sub-group within the group population

Question 8

steps of a stratified sample

Answer 8

1. identify the different strata that make the population
2. work out proportions for the representation
3. random sampling selects the ppts for each stratum

Question 9

DIFFERENCE BETWEEN AN OPPORTUNITY SAMPLE AND A VOLUNTEER SAMPLE

Answer 9

opportunity = select anyone willing and available, just asking whoever happens to be around
volunteer = self-selection, ppts select themselves to be in the sample

Question 10

good thing about systematic sampling?

Answer 10

avoids researcher bias because they have no choice but to have every Nth number, they are also usually fairly representative

Question 11

stratified sample - avoids researcher bias and representative sample BUT

Answer 11

isn’t perfect because the strata that are chosen cant reflect all the ways people are different

Question 12

evaluate opportunity sample

Answer 12

its convenient and saves time / effort

unrepresentative because its drawn from a particular area, and researcher bias is BIG

Question 13

why is volunteer sampling a problem?

Answer 13

requires minimal effort and is less time consuming BUT asking for volunteers attracts a certain time of people - helpful and keen

Question 14

define BIAS (in sampling)

Answer 14

when certain groups may be over or under-represented within the selected sample - like too many young people, too many white people .
limits generalisation

Question 15

define GENERALISATION

Answer 15

the extent that findings and conclusions can be broadly applied to the wider population - made possible when the sample of ppts is representative of the population