2.4.1 Reliability Flashcards
(9 cards)
what is Internal Reliability?
The extent to which a test or measure is consistent within itself
e.g. the use of standardised instructions and procedures for all participants
what is External Reliability?
The extent to which a test produces consistent results over several occasions
what are reliability issues?
Lack of operationalisation of the variables is a potential issue.
If you do not clearly state how you are defining and measuring your variables, this makes replication impossible and makes inter-rater reliability issues more likely
Order effects can occur in a repeated measures design.
Whilst completing the second condition the participant can become practiced/better at the task the second time round, or they can underperform due to factors such as boredom.
A lack of standardised procedures, inconsistency of measuring tools and an uncontrolled environment all jeopardise reliability
how do you deal with reliability issues?
Increasing levels of control in a study raises reliability – using a standardised procedure, instructions and scientific measuring equipment (e.g. PET/ MRI scans over self-reported ‘feelings’) and conducting the research in a laboratory environment helps to overcome most reliability issues.
The greater the level of control, the lower the risk of extraneous variables effecting results.
how do you deal with order effects
Order effects can be combatted with counterbalancing.
This involves splitting the population/sample into two halves; the first half complete condition one followed by condition two, the second half complete condition two followed by condition one.
This in effect negates the impact of order/practice effects, as both conditions are affected equally, and increases internal reliability
what is assessing reliability?
measures used to check the consistency of a set of
results/findings
what is Split-half reliability/testing?
involves splitting a participant’s test answers in half and seeing whether s/he got the same or similar scores on the two halves.
If so, internal reliability is high; if not, it is low and individual questions would need to be re-ordered or redesigned to improve reliability
what is Test-retest reliability:
involves testing and retesting the same participants over time, with the same test, and comparing their scores. If the scores are the same, the test has external reliability.
what is Inter-rater reliability?
where two or more psychologists produce consistent results by using a standardised procedure, agreed coding system, or correlation of their data.
