Research Methods : Sampling Flashcards
population
large group of people researcher intersted in studying e.g women in thirties
why is population aka target population
subset of general pop
why is it impossible to include all memebers of target populaiton
economical and practical reasons
as its not economci and practical to include all members of TP what do r do
selects sample
ideally sample drawn is
Representative of the target population
why ideally is sample drawn representative of the target population
generalisation of findings becoming practical
why is it difficult to represent populations in any sample
inevitably diverse nature of pop of people e.g gender , age .life experiences
inevitability vast of samples include
degree of bias
samples are selected using
sampling technique
sampling techs aim to produce
a representative sample
random sample
all mems of TP have equal chance of being selected
outline steps of getting a random sample
get list of all names of TP
assing names a number
actual sample selected using lottery method . e.g picking #out of hat
Systematic sample
every nth mem of TP selected
give example of systematic sampling
every 5th student in a class
sampling frame
list of people in TP organised e.g alphabetical
how do you do systematic sampling
establish sampling frame
nominate sampling sustem (e.g every 6th person)
begin from randomly determined start
work through sampling frame till complete
why do you begin from a randomly detrmined start
reduce bias
stratified sampling
composition of sample reflects proportions of people in certain subgroups in TP / Wider population
outline how to carry out startified sampling
identify diff starta that make up population
proportions for sample to be representative worked out
pt make up each starta selected through random sampling
opportunity sampling
researcher select anyone willing and available (opportunity sample )
Why would you use opportunity sampple
representative samples of TM difficult to obtain
t/f researcher taking whoever available at the time on street for a study is OS
T
Volunteer sample
pt selecting themselves to be pt of a sample
volunteer sample aka
self - selection