2. INSTRUMENTS…
Instruments: Collections of items or
questions intended to measure,
collectively (total score) levels of
theoretical variables (constructs) not
easily observable directly.
3. THE TYPES OF INSTRUMENTS…
1. Cognitive Instruments
2. Affective Instruments
3. Projective Instruments
4. 1. COGNITIVE INSTRUMENTS...
Measure an individual’s
attainment in academic areas
typically used to diagnose
strengths and weaknesses
5. TYPES OF COGNITIVE INSTRUMENTS...
1. Achievement tests
…provide information about how well the test takers
have learned what they have been taught in school
…achievement is determined by comparing it to the
norm, the performance of a national group of
norm
similar students who have taken the same test
6. 2. Aptitude tests
…measure the intellect and abilities not normally
taught and often are used to predict future
performance
…typically provide an overall score, a verbal score,
and a quantitative score
7. 2. AFFECTIVE INSTRUMENTS...
Measure characteristics of individuals along a number
of dimensions and to assess feelings, values, and
attitudes toward self, others, and a variety of other
activities, institutions, and situations
8. TYPES OF AFFECTIVE INSTRUMENTS...
1. attitude scales
…self-reports of an individual’s beliefs, perceptions, or
feelings about self, others, and a variety of activities,
institutions, and situations
…frequently use Likert, semantic differential,
Thurstone , or Guttman scales
9. 2. values tests
…measure the relative strength of an individual’s valuing
of theoretical, economic, aesthetic, social, political, and
religious values
10. 3. Personality inventories
…an individual’s self-report measuring how behaviors
characteristic of defined personality traits describe that
individual
12. PRIMARY TYPE OF PROJECTIVE TEST...
1. Associational tests
…participants react to a stimulus such as a
picture, inkblot or word onto which they
project a description
13. STEPS IN CONSTRUCTING AN INSTRUMENT
1) Determine clearly what it is you want to measure.
2) Generate a pool of possible items (about 60 for a 20 item
instrument).
3) Decide on question format (yes/no, strongly agree, agree, etc)
4) Decide how to score the instrument (e.g. on an optimism scale,
all responses that indicate optimism should get higher scores, so
that the more optimistic you are, the higher your total score).
5) Administer the instrument to a pilot sample of people: 100 - 300.
6) Scale purification: Evaluate each item using the pilot data
14. RULES GOVERNING THE SELECTION
INSTRUMENTS...
1. The highest validity
2. The highest reliability
3. The greatest ease of administration, scoring, and
interpretation
4. Test takers’ lack of familiarity with instrument
5. Avoids potentially controversial matters
15. SELECTING AN INSTRUMENT...
1. Determine precisely the type of
instrument needed
2. Identify and locate appropriate
instruments
3. Compare and analyze instruments
4. Select best instrument
16. ADMINISTERING THE INSTRUMENT...
1. Make arrangements in advance
2. Ensure ideal testing environment
3. Be prepared for all probable
contingencies
17. TWO ISSUES IN USING INSTRUMENTS...
1. Validity: the degree to which the
Validity
instrument measures what it purports
to measure
2. Reliability: the degree to which the
Reliability
instrument consistently measures
what it purports to measure
18. TERMS ASSOCIATED WITH INSTRUMENTS
1. DATA
2. CONSTRUCTS
3. VARIABLE
4. RAW SCORES
5. MEASUREMENT SCALES
19. Data…
Data
…the pieces of information researchers
collect through instruments to
examine a topic or hypothesis
25. MEASUREMENT SCALES...
Quantitative (continuous)
(
1. Ordinal variables
“order”: classifies persons or objects and ranks them in terms
of the degree to which those persons or objects possess a
characteristic of interest
2. Interval variables
ranks, orders, and classifies persons or objects according to
equal differences with no true zero point
3. Ratio variables
ranks, orders, classifies persons or objects according to equal
differences with a true zero point
