definitions Flashcards
Hypotheses
Hypotheses are statements about the prediction of the results, that can be verified or disproved by some investigation.
null hypotheses
these predict that no difference will be found in the results between the conditions. Typically these are written ‘There will be no difference…’
One-tailed (directional) hypotheses
state the specific direction the researcher expects the results to move in, e.g. higher, lower, more, less. In a correlation study, the predicted direction of the correlation can be either positive or negative.
Two-tailed (non-directional) hypotheses
these state that a difference will be found between the conditions of the independent variable but does not state the direction of a difference or relationship.
volunteer sample
Volunteer sample: where participants pick themselves through newspaper adverts, noticeboards or online.
opportunity sampling
Opportunity sampling: also known as convenience sampling, uses people who are available at the time the study is carried out and willing to take part. It is based on convenience.
random sampling
Random sampling: when every person in the target population has an equal chance of being selected. An example of random sampling would be picking names out of a hat.
systematic sampling
Systematic sampling: when a system is used to select participants. Picking every Nth person from all possible participants. N = the number of people in the research population / the number of people needed for the sample.
stratified sampling
Stratified sampling: when you identify the subgroups and select participants in proportion to their occurrences.
operationalization
Operationalization of variables means making them measurable/quantifiable. We must use operationalization to ensure that variables are in a form that can be easily tested.
independent groups design
Independent design (between-groups design): each participant is selected for only one group. With the independent design, the most common way of deciding which participants go into which group is by means of randomization.
matched pairs design
Matched participants design: each participant is selected for only one group, but the participants in the two groups are matched for some relevant factor or factors (e.g. ability; sex; age).
repeated measures
Repeated measures design (within groups): each participant appears in both groups, so that there are
exactly the same participants in each group.
counterbalancing
Counterbalancing is the best way of preventing order effects from disrupting the findings of an experiment, and involves ensuring that each condition is equally likely to be used first and second by the participants.
case studies
Case studies are in-depth investigations of a person, group, event, or community. It uses information from a range of sources, such as from the person concerned and also from their family and friends.