scientific processes Flashcards
what is an aim
what a researcher sets out to study and find out
what is a one tailed hypothesis
(directional) Points to what direction the effect will appear in,
eg if someone thought student’s attendance affects their grades, one tailed hypothesis would be that students with higher attendance will have better grades then those with lower attendance
what is a two tailed hypothesis
(non-directional) will still predict that there will be an effect, but will not say what direction it will appear in. EG, in the same study, a two-tailed hypothesis might look like, there will be a significant difference in the grades of students with high attendance and students with low attendance
what is a null hypothesis
separate as it says that there will not be a psychological test in either condition.
what is a sample
the process of selecting participants from the population.
what is random sampling
each person is equally likely to be selected.
what are the advantages of random sampling
free from BIAS as all members of sample have an equal chance if being particuipated
what are disadvantages of random sampling
If the sampling frame is large random sampling may be impractical.
A complete list of the population may not be available.
Minority subgroups within the population may not be present in sample.
what is a volunteer in sampling
putting yourself forward to be used in a sample
what are the advantages of volunteers
gives access to a variety of participants which may be more representative
what are disadvantages of volunteers
may all display similar characteristics (such as being more trusting or cooperative than those who did not apply) thus increasing the chances of yielding an unrepresentative sample.
what is opportunity sampling
used to select participants from a target group to take part in a research study. It consists of the researcher selecting anyone who is available and willing to take part in the study.
what are the advantages of opportunity sampling
It is a quick and easy way of choosing participants for a study as it is based on convenience
what are the disadvantages of opportunity sampling
It may not be representative of the target population, potentially producing a sampling bias, and so the findings will lack external validity as they cannot be generalised.
what is a pilot study
small, trial versions of proposed studies to test their effectiveness and make improvements
what are independent groups
participants only take part in one of the conditions
what are the advantages of independent groups
no order effects
what are the disadvantages of independent groups
individual differences
what are repeated measures
experimental design where the same participants take part in each condition of the experiment.
advantages of repeated measures
no individual differences
disadvantages of repeated measures
order effects
what are matched pairs
where pairs of participants are matched in terms of key variables, such as age and IQ.
what are advantaged of matched pairs
there are no order effects, and demand is lower because all participants are tested only once.
what are disadvantages if matched pairs
can take up more financial resources than the other experimental designs because it requires more participants.