validity and reliability

What is validity

Extent to which an observed effect is genuine

What is internal validity

Extent to which the observed effect is due to manipulation of IV and no tornero factors

What is face validity

Validity that checks if the measure is measuring the DV or IV

What is concurrent validity

Extent of a psychological measure relating to an existing measure

What is external validity

Extent of results being able to generalise to and across other situations

What is ecological validity

If you can generalise results to other settings and situations

What is population validity

If you can generalise the results to a large group of people

What is temporal validity

S results can be generalised to different time periods

What can affect internal validity

Demand characteristics

What is reliability

Consistency and accuracy of findings in an investigation

What is internal reliability

Internal consistency among items in a test

What is the split half method

Data collected, randomly split in half and compared

What is external reliability

If a measure is consistent when tested over time or by different individuals

What is test-retest

Assessing same individual on 2 different occasions and correlating results

What is inter rather reliability

Measured by correlating rating scores, must be over 80% for it to be reliable

How to improve reliability and validity

Standardisation ensures all materials and instructions are the same for everyone

Randomisation ensures each participant has equal probability of being allocated a condition