sampling Flashcards
sample
A sample is the group of people selected to represent the population in a study
population
A population is a group, sharing one or more characteristics, from which a sample is drawn
sampling technique
sampling technique is the method used to obtain the participants for a study from the population.
3 types
1-volunteer
2-opportunity
3-random
opportunity
Opportunity sampling is when the participants are chosen because they are available at the time and place where the research is taking place.
strengths of op
1-Large numbers of
participants can be
obtained
2-quickly obtained as they are already available
weaknesses of op
-non representative (cant genarlise)of the population
people who are available limited so this means a SAMPLE BIAS
volunteer
Volunteer sampling is when
participants react to a invited to take part in studies via advertisements or emails.
volunteer ad
1-more ethical
2-more committed as they volunteer so less likely to drop out
3-easy to obtain as they come to the researcher
dis of volu
-non representative of as people who respond may all be similar ex: all have free time
random
Random sampling is when all members of the population are allocated number and a fixed amount of these are chosen in an unbiased way, for example,
picking out numbers from a hat or a school list
strengths of random
1-representative of population as all have equal chance of getting chosen
weakness of random
-list may be incomplete so not a equal chance