sampling Methods

Question 1

Define target population

Answer 1

Large group of individuals the researcher is interested in studying.

Question 2

define opportunity sampling. (+and -)

Answer 2

PPts happen to be available at the time of study. (Recruited Conveniently)
+
Easy
Less costly
-
Not representative
Researcher bias

Question 3

Define random sampling (+ and -)

Answer 3

All members of a population have equal chance of being selected.
+
No researcher bias
-
Time consuming
Volunteer bias- ppts can refuse to take part

Question 4

Define systematic sampling (+ and -)

Answer 4

predetermined system used whereby every nth member selected from the sampling frame.
+
no researcher bias
fairly representative
-
Not truly unbiased unless random no. generator used.

Question 5

Define stratified sampling (+ and -)

Answer 5

composition of the sample reflects the varying proportions of people in particular subgroups with the wider community.
+
No researcher bias
Representative data -> generalisation is possible.
-
Time consuming
cannot reflect the differences between the [people of the wider population

Question 6

Define volunteer sampling.
(+ and -)

Answer 6

Involves self selection. ppts can offer to take part.
+
no researcher bias
Representative data
-
Volunteer bias
Motivations like money
May not take the study serious.