The document discusses different types of validity and reliability in psychological testing. It defines validity as the extent to which a test measures what it is intended to measure. There are several types of validity discussed, including content validity, face validity, criterion validity, construct validity, external validity, and internal validity. Reliability is defined as the degree to which a test consistently measures a construct. Types of reliability covered include test-retest reliability, parallel-forms reliability, internal consistency reliability, and inter-observer reliability.

1. By-
Akshay Madan 40490201818
Gautam Guglani 40590201818
Akshay Chaudhary
40690201818
Pushkar Kansal 40790201818
Harshit Nassa 40890201818

2.  Validity is a extent to which a test measures, what it is
supposed to measure.
 The questions of validity is raised in the context of
three points:
1. The form of the test
2. The purpose of the test
3. The population for whom it is intended

4.  External Validity:
1. External validity occurs when the casual relationship discovered can be
generalized to other people, time and contacts.
2. Correct sampling will allow generalized and hence give external validity.
 Internal Validity:
1. Internal validity occurs when it can be concluded that there is a casual
relationship between the variables being studied.
2. It is related to the design of the experiment.
 Content Validity:
1. When we want to find out if the entire content of the
behaviour/contruct/area is represented in the test we compare the test
task with the content of the behaviour.
2. This is a logical method, not an empirical one.
3. Example, if we to test knowledge of American Geography it is not fair to
have most questions linited to geography of New England.

5.  Face Validity:
1. Face validity occurs where something appears to be Valid.
2. This depends very much on the judgment of the observer.
 Test Validity:
1. Criterion: Correlation with the standards
2. Predictive: Predicts future value of criterion
3. Concurrent: Correlates with other test
 Construct Validity:
Construct validity accurately represents reality
1. Convergent: Simultaneous measure of same construct correlate
2. Discriminant: Dosen’t measure what it shouldn’t.

6.  Reliability is degree to which a test consistently
measures whatever it means.
 When a measurement procedure yields consistent
scores when the phenomenon being measured is not
changing.
 Degree to which scores are free of “Measuremnt Error”
 Consistency of the Measurement.

8.  Stability Reliability:
 Test-Retest:
1. Test-retest reliability is the degree to which scores are consistent over
time. It indicates score variation that occurs from testing sessions to testing
session of a result of errors of measurement.
2. Same test - different times.
3. Only works is phenomenon is unchanging.
4. Example: Administering the same questionnaire at 2 different times.

9. a) Equivalence Reliability:
 Inter-term Reliability: (internal consistency)
1. The association of answers to set of questions designed to measure the
same concept
2. Cronbach’s alpha is a statistic commonly used to measure inter-term
reliability which is based on the average of all the possible correlations of
all the split ½s of set of questions on the questionnaire

10. b. Parallel Form of Reliability:
Split-Half Reliability:
1. Especially appropriate when the test is very long. The most
commonly used method to split the test into two is using the odd-
even strategy.
2. Since longer tests tend to be more reliable, and since split-half
reliability represents the reliability of a test only half as long as the
actual test.
c. Inter Observer Reliability:
Correspondence between measures made by different observers.