Research methods - Reliability Flashcards
What is reliability?
How consistent a test or study is. In other words, does the test, when repeated in identical conditions or with similar participants, come up with the same results?
How can reliability be assessed?
Test-retest, the split-half method and correlating inter-observer reliability
What does test-retest involve?
Test-retest is when a study is repeated. If the results are similar both times, the test is said to have external reliability.
What is external reliability?
When a test or study should consistently produce the same results no matter the time given.
What are examples of external reliability?
A simple example would be if a doctor gave two pregnancy tests to a woman and the results came back positive both times. This means the test is reliable.
Another example would be a maths test. if a student took a maths test twice and got similar results, the test is said to have external reliability.
What is the split-half method?
The split-half is used to assess the internal reliability of a test. The split-half method takes one test and divides it into two sections. This can be even/odd numbered questions or first half/second half. If there is a positive correlation between both halves, the test is said to have internal reliability. In other words, a participant scores similar results in both sections of the tests
What is internal reliability in regards to the split-half method?
Internal reliability is looking at the same test - do all parts of the test have consistent results?
How is inter-observer reliability tested?
Tests from that were administered from different researchers are correlated to check if the results have a high positive correlation.
What is an example of inter-observer reliability ?
If two separate researchers are observing aggressive behaviour in 5-year olds, they should give the same score (1-10) for the same level of aggression. A 5yo who hits another child would receive a score of 10. If both researchers observed the behaviour and gave the same score of 10, then the test is said to have inter-observer reliability.
What can be done to improve validity and reliability?
Standardising research and operationalising variables.
What is standardised research?
Scientific studies follow strict guidelines and specific procedures. The procedures must be as specific as possible to make sure that there are as few extraneous variables as possible. These set procedures make sure that external reliability and inter-observer reliability are improved.
What is operationalising variables?
How the researcher defines and measures a specific variable as it is used in the study. This enables another psychologist to replicate your research and is essential in establishing reliability (achieving consistency in the results)
What can testing inter-observer reliability help avoid?
Inconsistent results due to the extraneous variable of different researchers.
