What is Measurement?

Ordering observations along a scale.
 

What is assessment?

Process of acquiring relevant information about an individual.
 

What is a test?

An objective standardized measure of a sample of behavior. The behavior chosen to be observed is an operational definition of some construct (characteristic) of interest.

How is meaning given to a test score?

A test derives its meaning only by comparison with the performance of others. Learning how to interpret and give meaning to tests will be a major part of the course.
 

SOME BASIC DEFINITIONS

Psychological measurement is a generic term for looking at psychological states and traits. It includes both Testing & Assessment.

Assessment is defined as any procedure that is used to gather information about people. The term 'assessment' refers to the problem-solving process of psychological evaluation. It involves much more than testing alone and, in fact, may not even involve testing.
 

Some non-testing forms of assessment include:

1. The Interview

A method of assessment involving direct, reciprocal communication. - Allows for wider sampling of behaviors.

Types:

Face-to face

Telephone

Computer
 

2. The Case Study

A method of assessment involving the compilation of data from various sources--mostly records, but also informants
 

3. Behavioral Observation

A method of assessment involving direct observation of behavior-- not always possible but VERY useful
 
 
 
 
 

TESTING

A test is a type of assessment that uses specific procedures to obtain information & then convert that information to numbers or scores.
 

The term 'testing' refers to the administration, scoring and interpretation of an instrument (procedure) designed to elicit information about performance in a sample of a particular area of behavior. The testing process includes mechanisms for:

selecting a set of items or test questions

specifying the conditions under which the test is administered

developing a system of scoring & interpreting responses
 

Tests vary in:

content,

format

administration procedures,

scoring,

interpretation procedures and

technical quality-- reliability/validity
 

The aim is to have scientifically selected items, and administration and scoring procedures that are universal.
 

Characteristics of a Good Test -

A good test is one that measures what it is designed to measure in as accurate a way as possible.

Has a clearly defined purpose. (What is it supposed to measure; who will take the test; how will test scores be used)

Has a specific & standard content.

Has a set of standard administration procedures.

Has a standard scoring procedure.

Possesses certain psychometric properties:

Is reliable

Is valid

Has good item statistics--patterns of responses

A fourth consideration is what method is used to compare an individual test taker to others. This is called normative data.

There are two forms of norming: one is norm-referenced and the other is criterion-referenced.

Norm-referenced means that the person is measured against all others taking the test.

Criterion-referenced means that the test is measured against some standard of behavior that is acceptable or not acceptable.

Assumptions Underlying Psychological Testing & Assessment
 

There are twelve assumptions that underlie psychological testing and assessment.
 

Assumption No. 1 - Psychological traits and states exist.

A trait has been defined as any distinguishable, relatively enduring way in which one individual varies from another. It is different from a state which only is temporary.
 

Assumption No. 2 - Psychological traits and states can be quantified and measured.

We usually measure them by scales and by scaling. Scaling is assigning numbers in accordance with empirical properties of objects or traits.
 

Assumption No. 3 - Various approaches to measuring aspects of the same thing can be useful.

Assumption No. 4 - Assessment (not just testing) can provide answers to some of life's most momentous questions.
 

Assumption No. 5 - Assessment can pinpoint phenomena that require further attention or study.

Assumption No. 6 - Various sources of data enrich and are part of the assessment process.

Assumption No. 7 - Various sources of error are part of the assessment process.

Error means something different in testing than it does in everyday life. In testing, error traditionally refers to something that is not only expected but also considered a component of the measurement process. It refers to a longstanding assumption that factors other than that which a test purports to measure will influence performance on the test. Because these factors change at different times and with different administrations, we often speak of error variance.
 

Assumption No. 8 - Tests and other measurement techniques have strengths and weaknesses.

Assumption No. 9 - Test-related behavior predicts non-test-related behavior.
 

Assumption No. 10 - Present-day behavior sampling predicts future behavior.
 

Assumption No. 11 - Testing and assessment can be conducted in a fair and unbiased manner.
 

Assumption No. 12 - Testing and assessment benefits society. If we didn't have forms of testing and assessment, somebody could decide they would call themselves a brain surgeon, for example, and there would be nobody around to evaluate whether they were actually capable of opening up your skull.
 

There are four parties in the process of assessment
 

The first is the developer.
 

2. The second party to the process is the test user.
 

The third party of testing and assessment is the test taker.

4. The fourth party in the testing and assessment process is society at-large.
 

What types of settings are assessments conducted in? And why?

There are four major settings in which testing and assessment is used:

(1) Educational settings -
 

(2) Counseling settings -
 

(3) Clinical settings -
 

(4) Business settings -
 

In these settings, tests are used for:

A. Rating people either in relation to peers or to some standard of performance

Placement- matching people with appropriate services or environments.

Selection - choosing people from a larger pool

Competency & Proficiency -

Diagnosis

Outcome & Evaluation