THE VALIDITY OF A TEST BATTERY USED IN THE SELECTION OF APPRENTICE ...

92 Pages·2012·0.81 MB·English

THE VALIDITY OF A TEST BATTERY USED IN THE
SELECTION OF APPRENTICE ELECTRICIANS
By
NIGEL ANDREW RITSON
Submitted in partial fulfilment of the requirements for the degree of:
MASTER OF ARTS
in the subj ect
INDUSTRIAL PSYCHOLOGY
at the
UNIVERSITY OF NATAL, DURBAN
SUPERVISOR: SONIA HILL
December 1999
DECLARATION OF ORIGINALITY
I hereby declare that this is the original work of the author unless specified in the text.
This dissertation has not been submitted for a degree at any other university.
Nigel Andrew Ritson
University of Natal, Durban
CONTENTS
Page
1
Acknowledgement
2
Abstract
Chapter One
Introduction 3
1.0 Background to the study 4
1.1 Purpose of the study 7
1.2 Outline of the investigation 8
Chapter Two
2.0 Historical Overview 10
2.1 Early theories 10
2.1.1 Psychometric theories of intelligence 11
2.1.2 Perceptual speed factor 17
2.1.3 Verbal comprehension factor 18
2.1.4 Number facility factor 18
2.1.5 Induction factor 18
2.1.6 Deduction factor 19
2.1.7 Spatial factor 19
2.2 Recent theories 20
2.2.1 Developmental theories 21
2.2.2 Learning theories 21
Summary 21
Chapter Three
3.0 Testing considerations in South Africa 23
Summary 31
Chapter Four
4.0 The assessment criteria 32
4.1 The predictors 33
4.1.1 Intermediate Battery Mental Alertness Test 34
4.1.2 Blox Test 35
4.1.3 Mechanical Comprehension Test 36
4.1.4 High Level Figure Classification Test (HL-FCT) 37
4.2 The criterion 38
4.3 The trade test 40
4.4 Identification of competencies 41
4.4.1 Verbal ability 43
4.4.2 Number facility 43
4.4.3 Induction factor 43
4.4.4 Deduction factor 44
4.4.5 Spatial ability 44
Summary 46
Chapter Five
5.0 Review of related research 48
Summary 55
Chapter Six
6.0 Test bias in the predictors 57
6.1 Item bias in the predictors 60
6.1.1 Mental Alertness test 61
6.1.2 High Level Figure Classification test 62
6.1.3 Blox test 63
6.1.4 Mechanical Comprehension test 63
6.2 Predictive bias results 64
Summary 65
Chapter Seven
7.0 Methodology 67
7.1 Analysis of results 68
7.2 Limitations of the study 73
7.2.1 Size of the sample 73
7.2.2 Restriction of range 74
7.2.3 Lack of a control group 75
7.3 Conclusions and recommendations 76
List of tables
Table 1.0 T-test for black and white group 69
Table 1.1 Correlation between predictor score stanines and trade test (blacks) 70
Table 1.2 Correlation between predictor score stanines and trade test (whites)71
Table 1.3 Correlation between raw predictor scores and trade test (blacks) 72
Table 1.4 Correlation between raw predictor scores and trade test (whites) 72
ACKNOWLEDGEMENTS
My sincere appreciation to all those who kept up their encouragement throughout.
The financial assistance of the Centre for Science Development towards this research is
hereby acknowledged. Opinions expressed and conclusions arrived at are those of the author
and are not necessarily to be attributed to the Centre for Science Development.
Special thanks to my family, and most of all to Leigh-Ann, who was my never-ending source
of motivation and support.
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ABSTRACT
The purpose of this study is to assess the suitability of a psychometric test battery that is
used by a large service department of the Durban City Council in the selection of
apprentice electricians. The essence of the investigation is to determine whether the tests
being used are appropriate for the purpose for which they are applied, as well as being
justifiable within the current context in South Africa. A predictive validity analysis was
carried out to determine whether the psychometric tests have a correlational relationship
with the trade test which apprentices undergo.
The analysis was carried out on a sample of fifty five apprentices, consisting of a black
group of 16 and a white group of 39. The results of the analysis were that the tests
generally did not have a positive link with the results of the trade test. The only
exception was the Mental Alertness test which showed a significant correlation with the
trade test for the white sample only.
The value of the study lies in its usefulness to the organisation which uses the test battery
in terms of providing a review of the effectiveness of the tests. Recommendations of the
study are that alternative methods for apprentice selection be investigated.
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CHAPTER ONE
INTRODUCTION
Psychometric assessment techniques have long been used in industry to assist in making
a variety of decisions regarding employees, most notably in the area of selection. The
rationale for using psychometric tests in the selection process lies in the purported ability
of the testing instrument to accurately and objectively assess the applicant's ability to
perform the work required in the job.
The guidelines compiled by the Society for Industrial Psychology of South Africa on the
use of personnel selection procedures states that the "underlying assumption of any
personnel selection procedure is that the procedures used can predict one or other
important and relevant behavioural requirement or job performance aspect of the
position" (Society for Industrial Psychology,1992:1. [Hereafter referred to as The
Guidelines D.
It would therefore follow that any organisation usmg a psychometric assessment
procedure in its selection of employees would be using such a method because it
significantly assists in predicting whether the applicant possesses the behavioural
requirements and competencies necessary to perform that job. On the basis of this an
informed decision as to whether or not to employ that person can be made with some
degree of accuracy.
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A selection instrument should clearly only be used if the above statement is true. If there
is any doubt regarding the ability of the test to provide an accurate idea of the applicant's
future performance in the job, then the test itself should be analysed for suitability of
purpose. This type of analysis should logically be carried out on a fairly regular basis to
ensure that the testing instrument remains useful and accurate as conditions such as job
requirements and applicant profile change.
Developments in South Africa since 1994 will ensure that the matter of psychometric
testing and selection emerges as an increasingly contentious and debated point of
concern. Pressure from labour is particularly imminent as unions are likely to become
increasingly concerned that their members' interests are protected against discriminatory
practises (Wheeler, 1993). It is envisaged that in future human resource practitioners
will be increasingly required to defend their selection practises against accusations of
being discriminatory (Taylor, 1987a; Veldsman, 1990). Furthermore, the onus will be
placed on the practitioners to validate the tests they use and to give concrete empirical
evidence that their selection practices are fair (The Guidelines, 1992). Psychometric
tests will surely come under the greatest amount of scrutiny because of the suspicion that
they may be biased against certain groups.
1.0 Background to the study
Durban Electricity, a large service department of the Durban Metropolitan Council,
makes use of a variety of psychometric tests. Based on the principles mentioned, they
select applicants on an annual basis for training as electrical apprentices.
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