NAME: Adaobi Chika Eze

REG No: ESUT/PG/M.Sc/10/11348

PSY: 770

ORIGIN AND DEVELOPMENMT OF PSYCHOLOGICAL

TESTING

PSYCHOLOGICAL TESTS

A psychological test is an instrument designed to measure

unobserved constructs, also known as latent variables.

Psychological tests are typically, but not necessarily, a series of

tasks or problems that the respondent has to solve.

Psychological tests can strongly resemble questionnaires,

which are also designed to measure unobserved constructs,

but differ in that psychological tests ask for a respondent's

maximum performance whereas a questionnaire asks for the

respondent's typical performance. A useful psychological test

must be both valid (i.e., there is evidence to support the

specified interpretation of the test results and reliable (i.e.,

internally consistent or give consistent results over time, across

raters, etc.).

It is important that people who are equal on the measured

construct also have an equal probability of answering the test

items correctly. For example, an item on a mathematics test

could be "In a soccer match two players get a red card; how

many players are left in the end?"; however, this item also

requires knowledge of soccer to be answered correctly, not just

mathematical ability. Group membership can also influence the

chance of correctly answering items (differential item

functioning). Often tests are constructed for a specific

population, and this should be taken into account when

administering tests. If a test is invariant to some group

difference (e.g. gender) in one population (e.g. England) it does

not automatically mean that it is also invariant in another

population (e.g. Japan).

PSYCHOLOGICAL ASSESSMENT

Psychological assessment is similar to psychological testing but

usually involves a more comprehensive assessment of the

individual. Psychological assessment is a process that involves

the integration of information from multiple sources, such as

tests of normal and abnormal personality, tests of ability or

intelligence, tests of interests or attitudes, as well as

information from personal interviews. Collateral information is

also collected about personal, occupational, or medical history,

such as from records or from interviews with parents, spouses,

teachers, or previous therapists or physicians. A psychological

test is one of the sources of data used within the process of

assessment; usually more than one test is used. Many

psychologists do some level of assessment when providing

services to clients or patients, and may use for example, simple

checklists to assess some traits or symptoms, but psychological

assessment is a more complex, detailed, in-depth process.

Typical types of focus for psychological assessment are to

provide a diagnosis for treatment settings; to assess a

particular area of functioning or disability often for school

settings; to help select type of treatment or to assess

treatment outcomes; to help courts decide issues such as child

custody or competency to stand trial; or to help assess job

applicants or employees and provide career development

counseling or training.

THE IMPORTANCE OF TESTING

Tests are used in almost every nation on earth for counseling,

selection, and placement. Testing occurs in settings as diverse

as schools, civil service, industry, medical clinics, and

counseling centers. Most persons have taken dozens of tests

and

thought nothing of it. Yet, by the time the typical individual

reaches retirement age, it is likely that psychological

test results will help shape his or her destiny. The deflection of

the life course by psychological test results might be subtle,

such as

when a prospective mathematician qualifies for an accelerated

calculus course based on tenth-grade achievement scores.

More commonly, psychological test results alter individual

destiny in profound ways. Whether a person is admitted to one

college

and not another, offered one job but refused a second,

diagnosed as depressed or not—all such determinations rest, at

least in part, on the meaning of test results as interpreted by

persons in authority.

Put simply, psychological test results change lives. For this

reason it is prudent—indeed, almost mandatory—that students

of psychology learn about the contemporary uses and

occasional abuses of testing. In Case Exhibit 1.1, the life-

altering aftermath

of psychological testing is illustrated by means of several true

case history examples.

The importance of testing is also evident from historical review.

Students of psychology generally regard historical issues as

dull, dry, and pedantic, and sometimes these prejudices are

well deserved.

After all, many textbooks fail to explain the relevance of

historical matters and provide only vague sketches of early

developments in mental testing. As a result, students of

psychology often conclude

incorrectly that historical issues are boring and irrelevant.

In reality, the history of psychological testing is a captivating

story that has substantial relevance to present-day practices.

Historical developments are pertinent to contemporary testing

for the following reasons:

THE CONSEQUENCES OF TEST RESULTS

The importance of psychological testing is best illustrated by

example. Consider these brief vignettes:

A shy, withdrawn 7-year-old girl is administered an IQ test by a

school psychologist. Her score is phenomenally higher than the

teacher expected. The student is admitted to a gifted and

talented program where she blossoms into a self-confident and

gregarious scholar.

Three children in a family living near a lead smelter are

exposed to the toxic effects of lead dust and suffer neurological

damage. Based in part on psychological test results that

demonstrate impaired intelligence and shortened attention

span in the children, the family receives an $8 million

settlement from the company that owns the smelter.

A candidate for a position as police officer is administered a

personality inventory as part of the selection process. The test

indicates that the candidate tends to act before thinking and

resists supervision from authority figures. Even though he has

excellent training and impresses the interviewers, the

candidate does not receive a job offer.

A student, unsure of what career to pursue, takes a vocational

interest inventory.

The test indicates that she would like the work of a pharmacist.

She

signs up for a prepharmacy curriculum but finds the classes to

be both difficult and boring. After three years, she abandons

pharmacy for a major in dance, frustrated that she still faces

three more years of college to earn a degree.

PSYCHIATRIC ANTECEDENTS

OF PSYCHOLOGICAL TESTING

Most historians trace the beginnings of psychological testing to

the experimental investigation of individual differences that

flourished in Germany and Great Britain in the late 1800s.

There is no doubt

that early experimentalists such as Wilhelm Wundt, Francis

Galton, and James McKeen Cattell laid the foundations for

modern-day testing, and we will review their contributions in

detail. But psychological testing owes as much to early

psychiatry as it does to the laboratories of experimental

psychology. In fact, the examination of the mentally ill around

the middle of the nineteenth century resulted in the

development of numerous early tests

(Bondy, 1974). These early tests featured the absence of

standardization and were consequently relegated to oblivion.

They were nonetheless influential in determining the course of

psychological testing, so it is important to mention a few

typical

developments from this era.

In 1885, the German physician Hubert von Grashey developed

the antecedent of the memory drum as a means of testing

brain-injured patients. His subjects were shown words,

symbols, or pictures

through a slot in a sheet of paper that was moving slowly over

the stimuli. Grashey found that many patients could recognize

stimuli in their totality but could not identify them when shown.

THE BRASS INSTRUMENTS

ERA OF TESTING

Experimental psychology flourished in the late 1800s in

continental Europe and Great Britain. For the first time in

history, psychologists departed from the wholly subjective and

introspective methods that had been so fruitlessly pursued in

the preceding

centuries. Human abilities were instead tested in laboratories.

Researchers used objective procedures that were capable of

replication. Gone were the days when rival laboratories would

have

raging arguments about “imageless thought,” one group saying

it existed, another group saying that such a mental event was

impossible. Even though the new emphasis on objective

methods and measurable quantities was a vast improvement

over the largely sterile mentalism that preceded it, the new

experimental psychology was itself a dead end, at least as far

as psychological testing was concerned. The problem was that

the

early experimental psychologists mistook simple sensory

processes for intelligence. They used assorted brass

instruments to measure sensory thresholds and reaction times,

thinking that such abilities

were at the heart of intelligence. Hence, this period is

sometimes referred to as the Brass Instruments era of

psychological testing.

In spite of the false start made by early experimentalists, at

least they provided psychology with an appropriate

methodology. Such pioneers as Wundt, Galton, Cattell, and

Clark Wissler showed

that it was possible to expose the mind to scientific scrutiny

and measurement. This was a fateful change in the axiomatic

assumptions of psychology, a change that has stayed with us

to the current day.

Most sources credit Wilhelm Wundt (1832– 1920) with founding

the first psychological laboratory in 1879 in Leipzig, Germany.

It is less well recognized that he was measuring mental

processes years before, at least as early as 1862, when he

experimented with his thought meter (Diamond, 1980). This

device was a calibrated pendulum with needles sticking off

from each side. The pendulum

would swing back and forth, striking bells with the needles. The

observer’s task was to take note of the position of the

pendulum when the bells sounded.

Wundt could adjust the needles beforehand and thereby know

the precise position of the pendulum when each bell was

struck. Wundt

thought that the difference between the observed pendulum

position and the actual position would provide a means of

determining the swiftness of thought of the observer. Wundt’s

analysis was relevant to a longstanding problem in astronomy.

The problem was that two or more astronomers simultaneously

using the same telescope (with multiple eyepieces) would

report

different crossing times as the stars moved across a grid line

on the telescope. Even in Wundt’s time, it was a well-known

event in the history of science that Kinnebrook, an assistant at

the Royal

Observatory in England, had been dismissed in 1796 because

his stellar crossing times were nearly a full second too slow

(Boring, 1950). Wundt’s analysis offered another explanation

that did not assume incompetence on the part of anyone. Put

simply, Wundt believed that the speed of thought might differ

from one person to the next: For each person there must be a

certain speed of

thinking, which he can never exceed with his given mental

constitution. But just as one steam engine can go faster than

another, so this speed of thought will probably not be the same

in all persons. (Wundt, 1862, as translated in Rieber, 1980)

DIFFERENTIATE BETWEEN PSYCHOLOGICAL TESTING

AND PSYCHOLOGICAL ASSESSMENT

Psychological Testing is "An objective and standardized

measure of a sample of behavior" while Psychological

Assessment is "An extremely complex process of solving

problems (answering questions) in which psychological tests

are often used as one of the methods of collecting relevant

data or the attempt of a skilled professional, usually a

psychologist, to use the techniques and tools of psychology to

learn either general or specific facts about another person,

either to inform others of how they function now, or to predict

their behavior and functioning in the future..

There are basically seven types of tests:

1. Group educational tests such as the California Achievement

Test

2. Ability and preference tests such as the Myers-Briggs

3. LD and neuropsychology tests such as the Halstead Reitan

Battery

4. Individual intelligence tests such as the WAIS and WISC

5. Readiness tests such as the Metropolitan Readiness Tests

6. Objective personality tests such as the MMPI2 or PAI

7. Self-administered, scored, and interpreted tests, such as

data base user qualification tests

There are generally three parties involved in testing according

to the Standards for Educational and Psychological Testing,

though this could become four:

Test Developer - This may be a company, an individual, a

school.... The Test Developer has certain responsibilities in

developing, marketing, distributing tests and educating test

users.

Test User - This may be a counselor, a clinician, a personnel

official.... The Test User has certain responsibilities in selecting,

using, scoring, interpreting, and utilizing tests.

Test Taker - This may be the client in many cases. The Test

Taker has certain rights regarding tests, their use, and the

information gained from them.

Test Utilizer - may be the test taker, but in other cases

however, a business or organization may send a person to be

tested. Thus, the organization also has certain rights regarding

tests, their use, and the information gained from them.

The Test Developer should

Construct a manual containing all relevant information, such as

the development and purpose of the test information on

standardized administration and scoring data on the collection

and composition of the standardization sample information on

the test reliability and validity adequate information for the

educated consumer to determine the appropriate and

inappropriate use of the test references to relevant published

research regarding the test and its use information on correct

interpretation and application and possible sources of misuse,

as well as any bias in test construction or use. Support the

information provided with data. Adhere to all ethical guidelines

regarding advertising, distributing, and marketing testing

material.

The Test User should

Be aware of the limits of tests, in regards to reliability, validity,

standard error of measurement, confidence intervals, as well as

appropriate interpretation and use of the instrument. If you

have any questions about tests, consult the Mental

Measurement Yearbook, Tests in Print, or the 1984 Joint

Technical Standards for Educational and Psychological Testing.

Read the manual and understand all relevant information

Be responsible for assessing your own competence regarding

use of a test or the competence of those you employ for that

purpose adhering to the appropriate use of the test as stated in

the manual being aware of any test bias or client

characteristics that might decrease the validity of the test

results or interpretation and report it with the testing report of

selection, data, interpretation, and application. Protect test

security where such security is vital to test reliability and

validity.

Be aware of the dangers of automated testing services and

realize that they are to be used only by professionals. Inform

the client to be tested as to the purpose and potential use and

applicability of the testing materials and results, as well as who

will potentially have access to the results. The test user has the

responsibility to see that the results are made available and

used only for and by those specified in the consent agreement.

Obsolete information should be regularly purged from records.

Good test use

Good test use requires:

1. Comprehensive assessment using history and test scores

2. Acceptance of the responsibility for proper test use

3. Consideration of the Standard Error of Measurement and

other psychometric knowledge

4. Maintaining integrity of test results (such as the correct use

of cut-off scores)

5. Accurate scoring

6. Appropriate use of norms

7. Willingness to provide interpretive feedback and guidance to

test takers

A good test is both reliable and valid, and has good norms.

Reliability, briefly, refers to the consistency of the test results.

For example, IQ is not presumed to vary much from week to

week, and as such, test results from an IQ test should be highly

reliable. On the other hand, transient mood states do not last

long, and a measurement of such moods should not be very

reliable over long periods of time. A measurement of transient

mood state may still be shown reliable if it correlates well with

other tests or behavior observations indicative of transient

mood states.

Validity, briefly, refers to how well a test measures what it says

it does. In a simple way, validity tells you if the hammer is the

right tool to fix a chair, and reliability tells you how good a

hammer you have. A test of intelligence based on eye color

(blue eyed people are more intelligent than brown eyed

people) would certainly be reliable, because eye color doesn't

change, but it would not be very valid, because IQ and eye

color have little to do with each other.

Norms are designed to tell you what the result of measurement

(a number) means in relation to other results (numbers). The

"normative sample" should be very representative of the

sample of people who will be given the test. Thus, if a test is to

be used on the general population, the normative sample

should be large, include people from ethnically and culturally

diverse backgrounds, and include people from all levels of

income and educational status.

Psychological tests fall into several categories:

Achievement and aptitude tests are usually seen in educational

or employment settings, and they attempt to measure either

how much you know about a certain topic (i.e., your achieved

knowledge), such as mathematics or spelling, or how much of a

capacity you have (i.e., your aptitude) to master material in a

particular area, such as mechanical relationships. 

Intelligence tests attempt to measure your intelligence—that is,

your basic ability to understand the world around you,

assimilate its functioning, and apply this knowledge to enhance

the quality of your life. Or, as Alfred Whitehead said about

intelligence, “it enables the individual to profit by error without

being slaughtered by it.”[1] Intelligence, therefore, is a measure

of a potential, not a measure of what you’ve learned (as in an

achievement test), and so it is supposed to be independent of

culture. The challenge is to design a test that can actually be

culture-free; most intelligence tests fail in this area to some

extent for one reason or another.

Neuropsychological tests attempt to measure deficits in

cognitive functioning (i.e., your ability to think, speak, reason,

etc.) that may result from some sort of brain damage, such as

a stroke or a brain injury.

Occupational tests attempt to match your interests with the

interests of persons in known careers. The logic here is that if

the things that interest you in life match up with, say, the

things that interest most school teachers, then you might make

a good school teacher yourself.

Personality tests attempt to measure your basic personality

style and are most used in research or forensic settings to help

with clinical diagnoses. Two of the most well-known personality

tests are

• the Minnesota Multiphasic Personality Inventory (MMPI), or

the revised MMPI-2, composed of several hundred “yes or

no” questions, and

• the Rorschach (the “inkblot test”), composed of several

cards of inkblots—you simply give a description of the

images and feelings you experience in looking at the blots.

Specific clinical tests attempt to measure specific clinical matters,

such as your current level of anxiety or depression.

 

Psychological assessment

1. Frequently uses tests

2. Typically does not involved defined procedures or steps

3. Contributes to some decision process to some problem,

often by redefining the problem, breaking the problem down

into smaller pieces, or highlighting some part(s) of the

problem<

4. Requires the examiner to consider, evaluate, and integrate

the data

5. Produces results that can not be evaluated solely on

psychometric grounds

6. Is less routine and inflexible, more individualized.

The point of assessment is often diagnosis or classification.

These are the act of placing a person in a strictly or loosely

defined category of people. This allows us to quickly

understand what they are like in general, and to assess the

presence of other relevant characteristics based upon people

similar to them. There are several parts to assessment.

The Interviewer

Note that an interview can be conducted in many ways and for

a variety of purposes. Below are several aspects in which to

view an interview. Verbal and face-to-face - what does the

client tell you? How much information are they willing/able to

provide?

para-verbal- how does the client speak? At normal pace, tone,

volume, inflection? What is their command of English, how well

do they choose their words? Do they pick up on non-verbal

cues for speech and turn taking? How organized is their

speech?

situation - Is the client cooperative? Is their participation

voluntary? For what purpose is the interview conducted? Where

is the interview conducted?

There are really two kinds of Interviews, structured or

unstructured.

Structured - The SCID-R is the Structured Clinical Interview for

the DSM-III-R and is, as the name implies, an example of a very

structured. It is designed to provide a diagnosis for a client by

detailed questioning of the client in a "yes/no" or

"definitely/somewhat/not at all" forced choice format. It is

broken up into different sections reflecting the diagnosis in

question. Often Structured interviews use closed questions,

which require a simple pre-determined answer. Examples of

closed questions are "When did this problem begin? Was there

any particular stressor going on at that time? Can you tell me

about how this problem started?" Closed interviews are better

suited for specific information gathering.

Unstructured - Other interviews can be less structured and

allow the client more control over the topic and direction of the

interview. Unstructured interviews are better suited for general

information gathering, and structured interviews for specific

information gathering. Unstructured interviews often use open

questions, which ask for more explanation and elaboration on

the part of the client. Examples of open questions are "What

was happening in your life when this problem started? How did

you feel then? How did this all start?" Open interviews are

better suited for general information gathering.

Interviews can be used for clinical purposes (such as the SCID-

R) or for research purposes (such as to determine moral

development or ego state).

Behavioral Observations

How does the person act? Nervous, calm, smug? What they do

and do not do? Do they make and maintain eye contact? How

close to you do they sit? Often, behavior observations are some

of the most important information you can gather.

Behavioral observations may be used clinically (such as to add

to interview information or to assess results of treatment) or in

research settings (to see which treatment is more efficient or

as a DV).

IDENTIFY THE VARIABLES CAPABLE OF

CONFOUNDING THE OUTCOME OF ASSESSMENT.

HOW DO YOU CONTROL THESE VARIABLES

Confounding Variables

Confounding variables are variables that the researcher failed to control, or eliminate, damaging the internal validity of an experiment.

Confounding, interactions, methods for assessment of effect modification

Confounding, interactions, methods for assessment of effect modification; Strategies to allow/adjust for confounding in design and analysis

While the results of an epidemiological study may reflect the true effect of an exposure on the development of the outcome under investigation, it should always be considered that the findings may in fact be due to an alternative explanation.1

Such alternative explanations may be due to the effects of chance (random error), bias or confounding which may produce spurious results, leading us to conclude the existence of a valid statistical association when one does not exist or alternatively the absence of an association when one is truly present.1

Observational studies are particularly susceptible to the effects of chance, bias and confounding and all three need to be considered at both the design and analysis stage of an epidemiological study, so their potential effects can be minimised.

Confounding, interaction and effect modification

Confounding provides an alternative explanation for an association between an exposure (X) and an outcome. It occurs when an observed association is in fact distorted because the exposure is also correlated with another risk factor (Y). This risk factor Y is also associated with the outcome, but independently of the exposure under investigation, X. As a consequence, the estimated association is not that same as the true effect of exposure X on the outcome.

An unequal distribution of the additional risk factor, Y, between the study groups will result in confounding. The observed association may be due totally or in part to the effects of differences between the study groups other than the exposure under investigation.1

A potential confounder is any factor that might have an effect on the risk of disease under study. This may include factors with a

direct causal link the disease, as well as factors that are proxy measures for other unknown causes, such as age and socioeconomic status.2

In order for a variable to be considered as a confounder:

1. The variable must be independently associated with the outcome (i.e. be a risk factor).

2. The variable must be also associated with the exposure under study in the source population.

3. It should not lie on the causal pathway between exposure and disease.

Examples of confounding

A study found alcohol consumption to be associated with the risk of Coronary Heart Disease. However, smoking may have confounded the association between alcohol and CHD.

Smoking is a risk factor in its own right for CHD, so is independently associated with the outcome, and smoking is also associated with alcohol consumption because smokers tend to drink more than non-smokers.

Controlling for the potential confounding effect of smoking may in fact show no association between alcohol consumption and CHD.

Effects of confounding

Confounding factors, if not controlled for, cause bias in the estimate of the impact of the exposure being studied. The effects of confounding may result in:

An observed difference between study populations when no real difference exists.

An observed difference between study populations when a true association does exist.

An underestimate of an effect. An overestimate of an effect.

Controlling for confounding

Confounding can be dealt with either at the study design stage, or at the analysis stage providing sufficient relevant data have been collected. A number of methods can be applied to control for potential confounding factors and the aim of all of them is to make the groups as similar as possible with respect to the confounder.

Potential confounding factors may be identified at the design stage based on previous studies or because the factor may be considered as biologically plausible.

Controlling for confounding at the design stage

Randomisation (random allocation)

This is the ideal method of controlling for confounding because all potential confounding variables, both known and unknown, should be equally distributed in the study groups. It involves the random allocation (e.g. using a table of random numbers) of individuals to study groups. However, this method can only be used in experimental clinical trials.

Restriction

Restriction limits participation in the study to individuals who are similar in relation to the confounder. For example if participation in a study is restricted to non-smokers only, any potential confounding effect of smoking will be eliminated. However, a disadvantage of restriction is that it may be

difficult to generalize the results of the study to the wider population if the study group is homogenous.1

Matching

Matching involves selecting controls so that the distribution of potential confounders (e.g. age or smoking) is as similar as possible to that amongst the cases. In practice this is only utilised in case-control studies, but it can be done in two ways:

1. Pair matching - selecting for each case one or more controls with similar characteristics (e.g. same age and smoking habits)

2. Frequency matching - ensuring that as a group the cases have similar characteristics to the controls

Detecting the presence of confounding

The presence or magnitude of confounding in epidemiological studies is evaluated by observing the degree of discrepancy between the crude and adjusted estimates.1 One method to assess for the presence of confounding is to calculate the crude relative risk (without controlling for confounding) and compare this measure with the relative risk adjusted for the potential confounder. If the relative risk has changed and there is little variation between the stratum specific rate ratios, then there is evidence of confounding

It is inappropriate to use statistical tests to assess the presence of confounding, but the following methods may be used to minimise its effect

Controlling for confounding during analysis

Stratification

Stratification allows the association between exposure and outcome to be examined within different strata of the confounding variable, for example by age or sex. The strength of the association is initially measured separately within each stratum of the confounding variable.

Assuming the stratum specific rates are relatively uniform, they may then be pooled to give a summary estimate of the relative risk adjusted or controlled for the potential confounder. One drawback of this method is that the more the original sample is stratified, the smaller each stratum will become, and the power to detect associations is reduced. Standardisation is an example of stratification.

Multivariate analysis

As the number of confounders that can be controlled for simultaneously is limited, particularly as this may lead to small numbers in some strata, statistical modelling (e.g. logistic regression) is commonly used to control for more that one confounder at the same time.

Residual confounding

It is only possible to control for confounders in the analysis if data on confounders were accurately collected. Residual confounding occurs when a confounder has not been adequately adjusted for in the analysis. An example would be socioeconomic status, because it influences multiple health outcomes but is difficult to measure accurately.3

Random misclassification of a confounder can result in either an over- or under- estimate of the true effect of the exposure under investigation.

Interaction (effect modification)

Interaction occurs when the direction or magnitude of an association between two variables differs due to the effect of a third variable. It may reflect a cumulative effect of multiple risk factors which are not acting independently and produce a greater or lesser effect than the sum of the effects of each factor acting on its own.

How to Control of Confounding Variables are by:

• Randomization

• Matching

• Adjustment

– Direct

– Indirect (STRATIFIED METHODS)

– Mantel-Haenszel

• Multiple Regression

– Linear

– Logistic

– Poisson

– Cox

DISCUSS IN DETAIL THEORIES OF INTELLIGENCE>

WHAT ARE THE DIFFICULTIES ENCOUNTERED IN

INTELLIGENCE TESTING

Intelligence.

A creative person is usually very intelligent in the ordinary sense

of the term and can meet the problems of life as rationally as

anyone can, but often he refuses to let intellect rule; he relies

strongly on intuition, and he respects the irrational in himself and

others. Above a certain level, intelligence seems to have little

correlation with creativity--i.e., a highly intelligent person may not

be as highly creative. A distinction is sometimes made between

convergent thinking, the analytic reasoning measured by

intelligence tests, and divergent thinking, a richness of ideas and

originality of thinking. Both seem necessary to creative

performance, although in different degrees according to the task

or occupation (a mathematician may exhibit more convergent

than divergent thinking and an artist the reverse).

Theories of intelligence

Theories of intelligence, as is the case with most scientific

theories, have evolved through a succession of paradigms that

have been put forward to clarify our understanding of the idea.

The major paradigms have been those of psychological

measurement (often called psychometrics); cognitive psychology,

which concerns itself with the mental processes by which the

mind functions; the merger of cognitive psychology with

contextualism (the interaction of the environment and processes

of the mind); and biologic science, which considers the neural

bases of intelligence.

Psychometric theories

Psychometric theories have generally sought to understand the

structure of intelligence: What form does it take, and what are its

parts, if any? Such theories have generally been based on and

tested by the use of data obtained from paper-and-pencil tests of

mental abilities that include analogies (e.g., lawyer : client ::

doctor : ?), classifications (e.g., Which word does not belong with

the others? robin, sparrow, chicken, bluejay), and series

completions (e.g., What number comes next in the following

series? 3, 6, 10, 15, 21, ?).

Underlying the psychometric theories is a psychological model

according to which intelligence is a composite of abilities

measured by mental tests. This model is often quantified by

assuming that each test score is a weighted linear composite of

scores on the underlying abilities. For example, performance on a

number-series test might be a weighted composite of number,

reasoning, and possibly memory abilities for a complex series.

Because the mathematical model is additive, it assumes that less

of one ability can be compensated for by more of another ability

in test performance. For instance, two people could gain

equivalent scores on a number-series test if a deficiency in

number ability in the one person relative to the other was

compensated for by superiority in reasoning ability.

The first of the major psychometric theories was that of the

British psychologist Charles E. Spearman, who published his first

major article on intelligence in 1904. Spearman noticed what, at

the turn of the century, seemed like a peculiar fact: People who

did well on one mental ability test tended to do well on the others,

and people who did not do well on one of them also tended not to

do well on the others. Spearman devised a technique for

statistical analysis, which he called factor analysis, that examines

patterns of individual differences in test scores and is said to

provide an analysis of the underlying sources of these individual

differences. Spearman's factor analyses of test data suggested to

him that just two kinds of factors underlie all individual

differences in test scores. The first and more important factor

Spearman labeled the "general factor," or g, which is said to

pervade performance on all tasks requiring intelligence. In other

words, regardless of the task, if it requires intelligence, it requires

g. The second factor is specifically related to each particular test.

But what, exactly, is g? After all, calling something a general

factor is not the same as understanding what it is. Spearman did

not know exactly what the general factor might be, but he

proposed in 1927 that it might be something he labeled "mental

energy."

The American psychologist L.L. Thurstone disagreed not only with

Spearman's theory but also with his isolation of a single factor of

general intelligence. Thurstone argued that the appearance of

just a single factor was an artifact of the way Spearman did his

factor analysis and that if the analysis were done in a different

and more appropriate way, seven factors would appear, which

Thurstone referred to as the "primary mental abilities." The seven

primary mental abilities identified by Thurstone were verbal

comprehension (as involved in the knowledge of vocabulary and

in reading); verbal fluency (as involved in writing and in producing

words); number (as involved in solving fairly simple numerical

computation and arithmetical reasoning problems); spatial

visualization (as involved in mentally visualizing and manipulating

objects, as is required to fit a set of suitcases into an automobile

trunk); inductive reasoning (as involved in completing a number

series or in predicting the future based upon past experience);

memory (as involved in remembering people's names or faces);

and perceptual speed (as involved in rapidly proofreading to

discover typographical errors in a typed text).

It is a possibility, of course, that Spearman was right and

Thurstone was wrong, or vice versa. Other psychologists,

however, such as the Canadian Philip E. Vernon and the American

Raymond B. Cattell, suggested another possibility--that both were

right in some sense. In the view of Vernon and Cattell, abilities

are hierarchical. At the top of the hierarchy is g, or general ability.

But below g in the hierarchy are successive levels of gradually

narrowing abilities, ending with Spearman's specific abilities.

Cattell, for example, suggested in a 1971 work that general ability

can be subdivided into two further kinds of abilities, fluid and

crystallized. Fluid abilities are the reasoning and problem-solving

abilities measured by tests such as the analogies, classifications,

and series completions described above. Crystallized abilities can

be said to derive from fluid abilities and be viewed as their

products, which would include vocabulary, general information,

and knowledge about specific fields. John L. Horn, an American

psychologist, suggested that crystallized ability more or less

increases over the life span, whereas fluid ability increases in the

earlier years and decreases in the later ones.

Most psychologists agreed that a broader subdivision of abilities

was needed than was provided by Spearman, but not all of these

agreed that the subdivision should be hierarchical. J.P. Guilford,

an American psychologist, proposed a structure-of-intellect

theory, which in its earlier versions postulated 120 abilities. For

example, in an influential 1967 work Guilford argued that abilities

can be divided into five kinds of operations, four kinds of

contents, and six kinds of products. These various facets of

intelligence combine multiplicatively, for a total of 5 4 6, or 120

separate abilities. An example of such an ability would be

cognition (operation) of semantic (content) relations (product),

which would be involved in recognizing the relation between

lawyer and client in the analogy problem, lawyer : client :: doctor :

?. In 1984 Guilford increased the number of abilities proposed by

his theory, raising the total to 150.

It had become apparent that there were serious problems with

psychometric theories, not just individually but as a basic

approach to the question. For one thing, the number of abilities

seemed to be getting out of hand. A movement that had started

by postulating one important ability had come, in one of its major

manifestations, to postulating 150. Because parsimony is usually

regarded as one of several desirable features of a scientific

theory, this number caused some disturbance. For another thing,

the psychometricians, as practitioners of factor analysis were

called, didn't seem to have any strong scientific means of

resolving their differences. Any method that could support so

many theories seemed somewhat suspect, at least in the use to

which it was being put. Most significant, however, was the

seeming inability of psychometric theories to say anything

substantial about the processes underlying intelligence. It is one

thing to discuss "general ability" or "fluid ability," but quite

another to describe just what is happening in people's minds

when they are exercising the ability in question. The cognitive

psychologists proposed a solution to these problems, which was

to study directly the mental processes underlying intelligence

and, perhaps, relate them to the factors of intelligence proposed

by the psychometricians.

Cognitive theories

During the era of psychometric theories, the study of intelligence

was dominated by those investigating individual differences in

people's test scores. In an address to the American Psychological

Association in 1957, the American psychologist Lee Cronbach, a

leader in the testing field, decried the fact that some

psychologists study individual differences and others study

commonalities in human behaviour but never do the two meet. In

Cronbach's address his plea to unite the "two disciplines of

scientific psychology" led, in part, to the development of cognitive

theories of intelligence and of the underlying processes posited

by these theories. Without an understanding of the processes

underlying intelligence it is possible to come to misleading, if not

wrong, conclusions when evaluating overall test scores or other

assessments of performance. Suppose, for example, that a

student does poorly on the type of verbal analogies questions

commonly found on psychometric tests. A possible conclusion is

that the student does not reason well. An equally plausible

interpretation, however, is that the student does not understand

the words or is unable to read them in the first place. A student

seeing the analogy, audacious : pusillanimous :: mitigate : ?,

might be unable to solve it because of a lack of reasoning ability,

but a more likely possibility is that the student does not know the

meanings of the words. A cognitive analysis enables the

interpreter of the test score to determine both the degree to

which the poor score is due to low reasoning ability and the

degree to which it is a result of not understanding the words. It is

important to distinguish between the two interpretations of the

low score, because they have different implications for

understanding the intelligence of the student. A student might be

an excellent reasoner but have only a modest vocabulary, or vice

versa.

Underlying most cognitive approaches to intelligence is the

assumption that intelligence comprises a set of mental

representations (e.g., propositions, images) of information and a

set of processes that can operate on the mental representations.

A more intelligent person is assumed to represent information

better and, in general, to operate more quickly on these

representations than does a less intelligent person. Researchers

have sought to measure the speed of various types of thinking.

Through mathematical modeling, they divide the overall time

required to perform a task into the constituent times needed to

execute each mental process. Usually, they assume that these

processes are executed serially--one after another--and, hence,

that the processing times are additive. But some investigators

allow for partially or even completely parallel processing, in which

case more than one process is assumed to be executed at the

same time. Regardless of the type of model used, the

fundamental unit of analysis is the same: a mental process acting

upon a mental representation.

A number of cognitive theories of intelligence have evolved.

Among them is that of the American psychologists Earl B. Hunt,

Nancy Frost, and Clifford E. Lunneborg, who in 1973 showed one

way in which psychometrics and cognitive modeling could be

combined. Instead of starting with conventional psychometric

tests, they began with tasks that experimental psychologists were

using in their laboratories to study the basic phenomena of

cognition, such as perception, learning, and memory. They

showed that individual differences in these tasks, which had

never before been taken seriously, were in fact related (although

rather weakly) to patterns of individual differences in

psychometric intelligence test scores. These results, they argued,

showed that the basic cognitive processes might be the building

blocks of intelligence.

Following is an example of the kind of task Hunt and his

colleagues studied in their research. The experimental subject is

shown a pair of letters, such as "A A," "A a," or "A b." The

subject's task is to respond as quickly as possible to one of two

questions: "Are the two letters the same physically?" or "Are the

two letters the same only in name?" In the first pair the letters are

the same physically, and in the second pair the letters are the

same only in name.

The psychologists hypothesized that a critical ability underlying

intelligence is that of rapidly retrieving lexical information, such

as letter names, from memory. Hence, they were interested in the

time needed to react to the question about letter names. They

subtracted the reaction time to the question about physical match

from the reaction time to the question about name match in order

to isolate and set aside the time required for sheer speed of

reading letters and pushing buttons on a computer. The critical

finding was that the score differences seemed to predict

psychometric test scores, especially those on tests of verbal

ability, such as verbal analogies and reading comprehension. The

testing group concluded that verbally facile people are those who

have the underlying ability to absorb and then retrieve from

memory large amounts of verbal information in short amounts of

time. The time factor was the significant development here.

A few years later, the American psychologist Robert J. Sternberg

suggested an alternative approach to studying the cognitive

processes underlying human intelligence. He argued that Hunt

and his colleagues had found only a weak relation between basic

cognitive tasks and psychometric test scores because the tasks

they were using were at too low a level. Although low-level

cognitive processes may be involved in intelligence, according to

Sternberg they are peripheral rather than central. He proposed

that psychologists should study the tasks found on the

intelligence tests and then determine the mental processes and

strategies that people use to perform those tasks.

Sternberg began his study with the analogies tasks such as

lawyer : client :: doctor : ?. He determined that the solution to

such analogies requires a set of component cognitive processes:

namely, encoding of the analogy terms (e.g., retrieving from

memory attributes of the terms lawyer, client, and so on),

inferring the relation between the first two terms of the analogy

(e.g., figuring out that a lawyer provides professional services to a

client), mapping this relation to the second half of the analogy

(e.g., figuring out that both a lawyer and a doctor provide

professional services), applying this relation to generate a

completion (e.g., realizing that the person to whom a doctor

provides professional services is a patient), and then responding.

Using techniques of mathematical modeling applied to reaction-

time data, Sternberg proceeded to isolate the components of

information processing. He determined whether or not each

experimental subject did, indeed, use these processes, how the

processes were combined, how long each process took, and how

susceptible each process was to error. Sternberg later showed

that the same cognitive processes are involved in a wide variety

of intellectual tasks, and he suggested that these and other

related processes underlie scores on intelligence tests.

Other cognitive psychologists have pursued different paths in the

study of human intelligence, including the building of computer

models of human cognition. Two leaders in this field have been

the American psychologists Allen Newell and Herbert A. Simon. In

the late 1950s and early 1960s they worked with a computer

expert, Clifford Shaw, to construct a computer model of human

problem solving. Called the General Problem Solver, it could solve

a wide range of fairly structured problems, such as logical proofs

and mathematical word problems. Their program relied heavily on

a heuristic procedure called "means-ends analysis," which, at

each step of problem solving, determined how close the program

was to a solution and then tried to find a way to bring the

program closer to where it needed to be. In 1972, Newell and

Simon proposed a general theory of problem solving, much of

which was implemented on the computer.

Most of the problems studied by Newell and Simon were fairly

well structured, in that it was possible to identify a discrete set of

moves that would lead from the beginning to the end of a

problem. For example, in logical-theorem proving the final result

is known, and what is needed is a discrete set of steps that lead

to that solution. Even in chess, another object of study, a discrete

set of moves can be determined that will lead from the beginning

of a game to checkmate. The biggest problem for a computer

program (or a human player, for that matter) is in deciding which

of myriad possible moves will most contribute toward winning a

game. Other investigators have been concerned with less well-

structured problems, such as how a text is comprehended, or how

people are reminded of things they already know when reading a

text.

All of the cognitive theories described so far have in common

their primary reliance on what psychologists call the serial

processing of information. Fundamentally, this means that

cognitive processes are executed in series, one after another. In

solving an algebra problem, for example, first the problem is

studied, then an attempt is made to formulate some equations to

define knowns and unknowns, then the equations may be used to

solve for the unknowns, and so on. The assumption is that people

process chunks of information one at a time, seeking to combine

the processes used into an overall strategy for solving a problem.

For many years, various psychologists have challenged the idea

that cognitive processing is primarily serial. They have suggested

that cognitive processing is primarily parallel, meaning that

humans actually process large amounts of information

simultaneously. It has long been known that the brain works in

such a way, and it seems reasonable that cognitive models should

reflect this reality. It proved, however, to be difficult to distinguish

between serial and parallel models of information processing, just

as it had been difficult earlier to distinguish between different

factor models of human intelligence. Subsequently advanced

techniques of mathematical and computer modeling were brought

to bear on this problem, and various researchers, including the

American psychologists David E. Rumelhart and Jay L. McClelland,

proposed what they call "parallel distributed processing" models

of the mind. These models postulated that many types of

information processing occur at once, rather than just one at a

time.

Even with computer modeling, some major problems regarding

the nature of intelligence remain. For example, a number of

psychologists, such as the American Michael E. Cole, have argued

that cognitive processing does not take into account that the

description of intelligence may differ from one culture to another

and may even differ from one group to another within a culture.

Moreover, even within the mainstream cultures of North America

and Europe, it had become well known that conventional tests,

even though they may predict academic performance, do not

reliably predict performance in jobs or other life situations beyond

school. It seemed, therefore, that not only cognition but also the

context in which cognition operates had to be taken into account.

EXPLAIN THE TERM PERSONALITY, DISCUSS EXHAUSTIVELY THE THEORETICAL EXPLAINATION OF HUMAN PERSONALITY

Personality is the particular combination of emotional,

attitudinal, and behavioral response patterns of an individual.

Many creative people show a strong interest in apparent disorder,

contradiction, and imbalance; they often seem to consider

asymmetry and disorder a challenge. At times creative persons

give an impression of psychological imbalance, but immature

personality traits may be an extension of a generalized receptivity

to a wider-than-normal range of experience and behaviour

patterns. Such individuals may possess an exceptionally deep,

broad, and flexible awareness of themselves.

Studies indicate that the creative person is nonetheless an

intellectual leader with a great sensitivity to problems. He exhibits

a high degree of self-assurance and autonomy. He is dominant

and is relatively free of internal restraints and inhibitions. He has

a considerable range of intellectual interests and shows a strong

preference for complexity and challenge.

The unconventionality of thought that is sometimes found in

creative persons may be in part a resistance to acculturation,

which is seen as demanding surrender of one's personal, unique,

fundamental nature. This may result in a rejection of conventional

morality, though certainly not in any abatement of the moral

attitude.