research methods Flashcards
experimental method
involves the manipulation of an independent variable to measure the effect on the dependent variable. experiments may be laboratory, field, natural or quasi
aim
a general statement of what the researcher intends to investigate; the purpose of the study
hypothesis
a clear, precise, testable statement that states the relationship between the variables to be investigated. stated at the outset of every study
directional hypothesis
states the direction of the difference or relationship
non-directional hypothesis
does not state the direction
variables
any “thing” that can vary or change within an investigation. variables are generally used in experiments to determine if changes in one thing result in changes to another
independent variable (IV)
some aspect of the experimental situation that is manipulated by the researcher or changes naturally- so the effect on the DV can be measured
dependent variable (DV)
the variable that is measured by the researcher. any effect on the DV should always be caused by a change in the IV
operationalisation
clearly defining variables in terms of how they can be measured
extraneous variable (EV)
any variable other than the independent variable (IV) that my have an effect on the dependent variable (DV) if its not controlled. EVs are essentially nuisance variables that do not vary systematically with the IV
confounding variables
any variable, other than the IV that may have affected the DV so we cannot be sure of the true source of changes to the DV. Confounding variables vary systematically with the IV.
Demand characteristics
any cue from the researcher or from the research situation that may be interpreted by participants as revealing the purpose of the investigation. this may lead to a participant changing their behaviour within the research situation
investigator effects
any effect of the investigators behaviour (conscious or unconscious) on the research outcome (the DV) this may include everything from the design of the study to the selection of, and interaction with participants during the research process
randomisation
the use of chance in order to control for the effects of bias when designing materials and deciding the order of conditions
standardisation
using exactly the same formalised procedures and instructions for all participants in a research study
experimental design
the different ways in which the testing of participants can be organised in relation to the experimental conditions
independent groups design
participants are allocated to different groups where each group represents one experimental condition
repeated measures
all participants take part in all conditions of an experiment
matched pairs design
pairs of participants are first matched on some variables that may effect the DV. then one member from each pair is assigned to condition A and the other to condition B
random allocation
an attempt to control for participant variables in an independent groups design which ensures that each participant has the same chance of being in one condition as any other
counterbalancing
an attempt to control for the effects of order in a repeated measures design: half the participants experience the conditions in one order, and the other half in the opposite order.
laboratory (lab) experiment
an experiment that takes place in a controlled environment within which the researcher manipulates the IV and records the effect on the DV, whilst maintaining strict control of extraneous variables
field experiments
an experiment that takes place in a natural setting within which the researcher manipulates the IV and records the effect on the DV
natural experiment
an experiment where the change in the IV is not brought about by the researcher but would have happened even if the researcher had not been there. The researcher records the effect on the DV
quasi experiment
a study that is almost an experiment but lacks key ingredients. the IV has not been determined by anyone (the researcher or any other person) the “variables” simply exist such as being old or young. strictly speaking this is not an experiment
population
a group of people who are the focus of the researchers interest, from which a smaller sample is drawn
sample
a group of people who take part in a research investigation. the sample is drawn from a (target) population and is presumed to be representative of that population, i.e. it stands “fairly” for the population being studied
sample techniques
the method used to select people from the population
bias
in the context of sampling, when certain groups may be over or under represented within the sample selected. for instance, there may be too many younger people, or too many people of one ethnic origin in a sample. this limits the extent to which generalisations can be made to the target population
generalisation
the extent to which findings and conclusions from a particular investigation can be broadly applied to the population. this made possible if the sample of participants is representative of the population