CHAPTER 4: RELIABILITY Flashcards
Who is the founder of the advancement of reliability?
Charles Spearman
He wrote book “ The proof of measurement of associatuon between 2 things”
Charles Spearman
Who has this basic notion of sampling error?
Abraham De Moivre
Who created the Product Momentum Correlation?
Karl Pearson
Who is the founder of the foundation of reliability?
Edward Thorndike
He wrote the book “Into the theory of mental and social measurement”
Edward Thorndike
What are the three basic princples of Reliability?
SEM, Domain Sampling Method and IRT
A principle which the deviation of error of the true score and observed score is important to know the reliability of the test.
SEM
It is the reliability of variance of observed score in a short test and variance of long run to know the true score.
Domain Sampling Method
It uses computer that focus on the range of item difficulty to assess individual’s ability
IRT
What are the four sources of error?
test- retest method, parellel forms method, Internal consistency method and difference score
A method which to test the reliability of the test, a test used in different occassion. It measures “traits” over time
test -retest method
A method which we evaluate the test accross different forms of the test.
There are two forms of test but has the same item of difficulty
parallel forms method
A method which people are examine in the same subset of items selected from a same form of measurement
Internal consistency
It is the difference of the score of two groups.
difference score
What are the two effects of error?
Carry over and Practice effect
The effect which the first administration of the test is greater than the second one that leads to inconsistency or gap of the test results
Carry over
The effect which the second test result is high due to practice
Practice effect
A method of parallel forms
Alternate forms of parallel
What are the three methods of internal consistency?
Split half, KR20 Formula and Coefficient Alpha
It is way which a long test is split into half which the first half of the result is compare to the second one.
Split half
How to divide the items of the test?
Odd-even system
It is a formula which used to have a correct system of splitting the long test which has the correlation of two halves.
Spearman-Brown Formula
What formula is this?
r = 2r/1-r
Spearman-Brown Formula
A way of splitting which is used when has 2 unequal variance for non-dichotomous
Cronbach’s Coefficient Alpha
It is a method of test which calculates the reliability are dichotomous 0 or 1 or (right or wrong)
KR20 Formula
It is a method of test which describes the variance of items whether or not they are in a wrong or right format.
Coefficient Alpha
A method used for Difference of score
Kappa Statistics
He established the Kappa Statistics
J. Cohen
It is the best method of the level of agreement of 2 raters
Kappa Statistics
+1. -1
- 75
- 40 - .74
- 39
Perfect agreement
Excellent agreement
Fair / good agreement
Poor agreement
What formula is this?
S square root of 1 - r
SEM
How reliable is reliable?
- Depends on the use of tests
- Usually needed is a test with .70 - ,80
- If clinics, to the patient’s future greater than .95 is needed
How to improve reliability?
- Increase the no. of items based on Sampling Domain Effect and the Pearson - Brown method
- Perform Factor and Item analysis
- Correction of Attenuation
It examines the correlation between each item and total score for the test
Discriminability analysis
It examines the test if there have been no error
Correction of Attenuation
