Research Methods (Aims & Hypotheses) Flashcards
define hypothesis
a precise testable statement including levels of the independent variable and dependant variable (or both co-variables for a correlational study)
What is the independent variable in psychology
a factor that is directly manipulated by the experimenter in order to observe the effect of this on the variation of the DV. At least 2 levels of IV in the experiment.
What is the dependant variable in psychology
measured by the experimenter to assess the effects of the IV
Define experiment
investigations where a variable is manipulated/altered and its effect can be measured, while maintaining control over other variables that might interfere with this situation
What is a laboratory experiment
an experiment conducted in a very controlled environment, along with controlled tasks, where participants go to the experimenter.
What is a field experiment?
an experiment conducted in more everyday surroundings than a laboratory (more natural), where the experimenter goes to the participants.
What is experimental/alternative/research hypothesis
(it is a statement not a question) states there’s a change in the measurement of the DV as a manipulation of the IV. Includes both levels of the IV ( where any difference/change found is due to chance factors)
What is null hypothesis
(don’t use the term “relationship”) a statement that there is no change/difference in the measurement of the DV as a result of the manipulation of the IV.
what can alternate/experimental/research hypothesis be written as?
directional hypothesis (one-tailed hypothesis)ORnon-directional hypothesis (two-tailed hypothesis
what is non-directional (two-tailed) hypothesis
simply predicts there will be a difference/relationship between two conditions or two groups of people, but does not predict which way it will go.
what is directional (one-tailed) hypothesis
states the kind of difference/relationship between two conditions or two groups of participants , in terms of which group will do better or worse.
Define operationalisation
variables must be operationalised. Operationalised variables are carefully stated, demonstrating exactly how they are to be measurede.g. the DV would be “no words recalled” not “recall”. the IV needs to clearly state both levelse.g. “participants recalling in green light and participants recalling in blue light”
Define Aims
a general statement about what area or topic is being researched. Typically beginning with “to investigate…”. A concise and to the point statement directing the overall ambition of the study
According to scientific principle, what is the researcher described as in an experiment?
a neutral observer
When should a researcher use directional hypothesis?
if there is previous research suggesting which way the results are likely to go
Define Falsifiability
any theory must be open to the possibility that new research will emerge that contradicts its basic principles. The more a theory is able to withstand attempts to falsify it, the greater confidence we have in that theory, but this level of confidence never reaches 100% certainty.
what basis are hypothesis accepted/rejected on?
statistical testing, where strength of evidence is based on probability
Describe the standard practice
to accept results if data passes 0.05 level of significance ( 1 in 20 chance of results being a fluke).
example of alternative hypothesis
there will be a significant difference in the driving performance of males compared to females
example of null hypothesis
there will be no significant difference in the driving performance of males compared to females. Any difference will be due to chance factors.
example of directional hypothesis
people TAKE LONGER to state the colour of a word when it is written in a conflicting colour then when the word and the colour it is written in is the same
example of non-directional hypothesis
there will be a difference in the speed when people state the colour of a word when it is written in conflicting colour than when the word and the colour it is written in are the same
What does operationalising allow?
allows the study to be precisely replicated to check that the conclusions are reliable, which can increase objectivity as the outcome is measured the same way by all researchers, and the outcome is not open to interpretation.
what is the role of an experiment?
they set up a situation where the participant is required to perform a task and the performance of this task is measured.
What is the aim and knowledge status of the ppt in a field experiment?
to find a cause and effect conclusion so that scientific knowledge can be built.ppts are usually unaware that they’re taking part in the study.
what is the aim and knowledge status of the ppt in a lab experiment?
to find a cause and effect conclusion so that scientific knowledge can be built.ppts are usually aware that they are involved in the study.
Outline the experimental method
- Theory is proposed2. Hypothesis is made based on this proposed theory3. The variable is manipulated to produce the IV4. The performance is measured (the DV)5. The theory is supported or refuted according to the outcome
2 strengths of a lab experiment
High levels of control, where extraneous variables are minimised meaning higher chances that we can be sure the IV has caused this change in the DV, and not any other variable.Therefore causality can be established, meaning there is internal validity.High levels of control and standardisation in procedures, meaning it can easily be replicated. Therefore we can check for consistency in results, thus demonstrating reliability.
2 strengths of a field experiment
less artificial situation and tasks, leading to higher ecological validity. This makes field experiments useful as we can generalise findings to real situations, therefore increasing the usefulness of the study.Avoids demand characteristics as ppts are not aware they are being studied, therefore increasing the internal validity as ppts are acting naturally
2 weaknesses of a lab experiment
artificial, contrived situation where ppts may not behave naturally, leading to demand characteristics, therfore could affect internal validity as behaviour is not genuineartificial situation and task means research will lack ecological validity, meaning we are unable to generalise findings to real situations, therefore limiting the usfeulness of a study
2 weaknesses of a field experiment
difficult to control, meaning results could be affected by extraneous variables, therefore increasing internal validity as we cannot be sure the IV is the only thing that has caused a change in the DV.Due to lack of control over variables and limited standardisation, field studies can be difficult to replicate, meaning they cannot be repeated to check for consistency in results, therefore lowering reliability.
what is the ethical issue of a field experiment?
informed consent and debriefing may not be possible, so there may be ethical if ppts aren’t aware of being studied.
how do you determine if an experiment is laboratory or field?
depending on where the DV is tested
ecological validity
ability to generalise a research finding beyond the particular setting in which it is demonstrated, to other settings
what key features should be considered in an experiment to establish ecological validity
what task was used? does it have mundane realism?were ppts aware they were being studiedwhat was environment like
define mundane realism
the extent to which a task reflects what we ordinarily do
what is internal validity
concerns what is going on inside of an experiment, where the researcher is testing what they intended to test
what is extraneous variable
in an experiment, any variable other than the IV that might possibly affect the DV and thereby confuse the results (includes both ppt and situational variables)
ppt variable example
a characteristic of the ppt, such as age or intelligence
situational variable example
a feature of the environment that may affect performance, such as distracting noise or time of day
suggest ways to deal with extraneous variables
should be held constant, e.g all ppts should be similar age ORthe researcher must ensure such variables are randomly spread across conditions
