PYC4807: Introduction to Psychological Assessment in the South African context
(Oxford).
Fifth Edition.
This contains notes/summaries on Theme 1: Psychometric Theory, Topic 1.1.
Psychometric Properties needed for Assignment 1 (2022).
Chapter 4: Reliability:
Table 4.1. Aptitude scores of machine operators:
(can be used to do the calculations)
APTITUDE TEST SCORES
OPERATO
Score for odd Score for even Product of Total score Total score Product of
R
items items 𝒙𝟎 𝒙𝒆 (𝑿𝟏 )𝑻𝟏 (𝑿𝟐 )𝑻𝟐 (𝑿𝟏 𝑿𝟐 )
(𝒙𝟎 ) (𝒙𝒆 )
A 5 6 30 11 12 132
B 8 10 80 18 16 288
C 7 7 49 14 15 210
D 8 9 72 17 17 289
E 7 6 42 13 14 182
F 6 8 48 14 13 182
G 5 4 20 9 9 81
H 8 7 56 15 14 210
I 6 5 30 11 13 143
J 2 3 6 5 6 30
𝛴𝑋0 = 62 𝛴𝑋𝐸 = 65 𝛴𝑋0 𝑋𝑒 = 433 𝛴𝑋1 = 127 𝛴𝑋2 = 129 𝛴𝑋1 𝑋2 = 1747
𝛴(𝑋0 )2 = 416 𝛴(𝑋𝐸 )2 = 465 𝛴𝑋0 𝛴𝑋𝑒 = 4030 𝛴𝑋1 𝛴𝑋2 = 16383
Measurement is assigning numbers to objects using clearly specific rules.
If we repeatedly measure the same objects, these measures should provide us with a fairly
consistent result. For this measurement process, we should have a clear conception of at
least three aspects:
1. What is the entity that we want to measure (e.g., height, weight, etc.)?
2. What exactly is the nature of the measure that we want to use (e.g., a scale, ruler,
etc.)?
3. The application of the rules on how to measure the object we want to measure (e.g.,
with or without clothes, or shoes, etc.)
(Oxford).
Fifth Edition.
This contains notes/summaries on Theme 1: Psychometric Theory, Topic 1.1.
Psychometric Properties needed for Assignment 1 (2022).
Chapter 4: Reliability:
Table 4.1. Aptitude scores of machine operators:
(can be used to do the calculations)
APTITUDE TEST SCORES
OPERATO
Score for odd Score for even Product of Total score Total score Product of
R
items items 𝒙𝟎 𝒙𝒆 (𝑿𝟏 )𝑻𝟏 (𝑿𝟐 )𝑻𝟐 (𝑿𝟏 𝑿𝟐 )
(𝒙𝟎 ) (𝒙𝒆 )
A 5 6 30 11 12 132
B 8 10 80 18 16 288
C 7 7 49 14 15 210
D 8 9 72 17 17 289
E 7 6 42 13 14 182
F 6 8 48 14 13 182
G 5 4 20 9 9 81
H 8 7 56 15 14 210
I 6 5 30 11 13 143
J 2 3 6 5 6 30
𝛴𝑋0 = 62 𝛴𝑋𝐸 = 65 𝛴𝑋0 𝑋𝑒 = 433 𝛴𝑋1 = 127 𝛴𝑋2 = 129 𝛴𝑋1 𝑋2 = 1747
𝛴(𝑋0 )2 = 416 𝛴(𝑋𝐸 )2 = 465 𝛴𝑋0 𝛴𝑋𝑒 = 4030 𝛴𝑋1 𝛴𝑋2 = 16383
Measurement is assigning numbers to objects using clearly specific rules.
If we repeatedly measure the same objects, these measures should provide us with a fairly
consistent result. For this measurement process, we should have a clear conception of at
least three aspects:
1. What is the entity that we want to measure (e.g., height, weight, etc.)?
2. What exactly is the nature of the measure that we want to use (e.g., a scale, ruler,
etc.)?
3. The application of the rules on how to measure the object we want to measure (e.g.,
with or without clothes, or shoes, etc.)
