5.1 Measurement Concepts – Reliability Flashcards
A reliable measure does not ____ from one reading to the next. If the measure does fluctuate, there is error in the measurement device.
fluctuate
____ refers to the consistency or stability of a measure of behaviour.
Reliability
Any measure that you make can be thought of as comprising two components: (1) a ____ ____, which is the real score on the variable, and (2) ____ ____.
true score, measurement error
The ____ ____ ____ (symbolised as r) can range from 0.00 to +1.00 and 0.00 to -1.00. A correlation of 0.00 tells us that the two variables are not related at all. The closer a correlation is to 1.00 the stronger is the relationship.
Pearson correlation coefficient
When you read about reliability, the correlation will usually be called a ____ ____.
reliability coefficient
____-____ reliability is assessed by measuring the same individuals at two points in time.
Test-retest
____ ____ reliability is the assessment of reliability using responses at only one point in time.
Internal consistency
One indicator of internal consistency is ____-____ reliability; this is a correlation of the total score of one half of the test with the total score of the other half.
split-half
Another commonly used indicator of reliability based on internal consistency, called ____ ____, provides us with the average of all possible split-half reliability coefficients. The value of Cronbach’s alpha is based on the average of all the inter-item correlation coefficients and the number of items in the measure.
Cronbach’s alpha
It is also possible to examine the correlation of each item score with the total score based on all items. Such ____-____ correlations are very informative because they provide information about each individual item.
item-total
____ ____ is the extent to which raters, or researchers, agree in their observations.
Interrater reliability
