PSYCHOMETRIC TESTING
An objective resource for identifying and measuring qualities in individuals in order to make
informed decisions
Features –
Measures aspects of mental functions, abilities, preferences
Derived from rigorous, scientific and statistical methods
Objective and standardized
Behavioural characteristics measured
Describes behaviour categorically/numerically
Measures differences across people or across time in the same individual
Purpose –
Classification – belonging to specific category
Self-understanding – source of information
Program evaluation – effectiveness of particular program/intervention
Scientific enquiry
Comparison
Diagnostic assessments
What can be measured? –
Ability
Aptitude
Personality
Motivation
Emotional intelligence
Attitude
Characteristics of a good test –
Objectivity
Practicability
Reliability
Validity
Norms
Classification of tests –
Administrative conditions – individual, group
Scoring – objective, subjective
Time limit in producing response – speed test, power test
Nature of items – verbal, non-verbal, performance, non-language
Purpose or objective – intelligence, aptitude, personality, neuropsychological test,
achievement
, SCALES OF MEASUREMENT
1. Nominal Scale
- Applicable for categorical variables
- Not a measure of quantity
- Example – eye colour, marital status, country of origin
- Can compute – frequency distribution
2. Ordinal Scale
- Ability to rank in order of magnitude
- Does not have equal intervals
- Example – ranking food preferences
- Can compute – frequency distribution, median, percentiles
3. Interval Scale
- Classifies data into groups or categories
- Designates equal item ordering
- Possesses equal intervals
- Lacks true zero point, has arbitrary zero point
- Example – temperature, IQ
- Can compute – frequency distribution, median, percentile, addition, subtraction,
mean, SD, correlation, regression, ANOVA
4. Ratio Scale
- Highest level
- Has all attributes of interval scale and a true zero point
- Clearly defines magnitude or value of difference
- Example – heart beats per minute
- Can compute – all of the above, ratio
An objective resource for identifying and measuring qualities in individuals in order to make
informed decisions
Features –
Measures aspects of mental functions, abilities, preferences
Derived from rigorous, scientific and statistical methods
Objective and standardized
Behavioural characteristics measured
Describes behaviour categorically/numerically
Measures differences across people or across time in the same individual
Purpose –
Classification – belonging to specific category
Self-understanding – source of information
Program evaluation – effectiveness of particular program/intervention
Scientific enquiry
Comparison
Diagnostic assessments
What can be measured? –
Ability
Aptitude
Personality
Motivation
Emotional intelligence
Attitude
Characteristics of a good test –
Objectivity
Practicability
Reliability
Validity
Norms
Classification of tests –
Administrative conditions – individual, group
Scoring – objective, subjective
Time limit in producing response – speed test, power test
Nature of items – verbal, non-verbal, performance, non-language
Purpose or objective – intelligence, aptitude, personality, neuropsychological test,
achievement
, SCALES OF MEASUREMENT
1. Nominal Scale
- Applicable for categorical variables
- Not a measure of quantity
- Example – eye colour, marital status, country of origin
- Can compute – frequency distribution
2. Ordinal Scale
- Ability to rank in order of magnitude
- Does not have equal intervals
- Example – ranking food preferences
- Can compute – frequency distribution, median, percentiles
3. Interval Scale
- Classifies data into groups or categories
- Designates equal item ordering
- Possesses equal intervals
- Lacks true zero point, has arbitrary zero point
- Example – temperature, IQ
- Can compute – frequency distribution, median, percentile, addition, subtraction,
mean, SD, correlation, regression, ANOVA
4. Ratio Scale
- Highest level
- Has all attributes of interval scale and a true zero point
- Clearly defines magnitude or value of difference
- Example – heart beats per minute
- Can compute – all of the above, ratio
