Date: Wed, 6 Dec 1995 23:58:43 -0800
From: Rima & Kim McKinzey rkm[AT SYMBOL GOES HERE]SLIP.NET
Subject: Vocabulary & IQ
As the psychologist husband in question, I've been asked to clarify.
First, I qualify as a well-educated, up-to-date, licensed clinical
psychologist (Ph.D.). I'm a member of APA, & have been an examiner for CA.
I am qualified to document a person's IQ (whether for SSI, school, court,
or Mensa), and keep informed on available indices of IQ.
I don't think there's a better intro to the topic than Matarrazzo. I defer
to him as an authority.
IQ isn't a difficult concept; the various definitions are usually
summarized as "figuring things out," altho I prefer "adapting to novel
tasks." Once the concept has been operationalized (i.e., a criterion has
been agreed upon), standarized measures can be devised to fulfill the need
for the measure. Historically, that need came when schools sought a way of
giving special aid to the lower 2% of the child population, and again when
this nation's military sought a way of making the most of the hordes of men
suddenly being processed at the entry of WWI.
As psychologists kept at it, our tests got more sophisticated (the WAIS-III
is in development!). Spearman's G (the notion of a general, overarching
factor) and related special intellectual abilities (see the description of
Gardner's ideas) seemed pretty reasonable as an approach. My predecessors
discovered that once a G score (such as the WAIS-R FSIQ) was formulated,
Vocabulary (followed by Similarities) correlated the highest with the
overall score in both adults and children. Hence, the PPVT, Shipley ILS,
and shorter forms of the WAIS usually include some well-normed measure of
vocabulary. Hence, Rima's carefully chosen "vocabulary is amongst our best
Now: what to do about people who are not from the normative population? We
have a host of "culture-free" tests; I like the Raven Progressive Matrices
best. Those tests use language-free problems to get at the IQ, and do
acceptably at getting at IQ potential.
The referral question must be considered. If the question is: this child
is having trouble in school. Should we give special attention to her? The
answer is, yes, why do you need an IQ? If the question is: will this
applicant do well in a computer customer service position? I'll use a
highly verbal test, or even verbal ability during an interview. If the
question is : should we kill this defendant, or let him live? The answer
is: here are the results of both verbal and non-verbal measures, plus many
it is historically characteristic of reductionist thinking in psychology
to equate vocabulary with intelligence.
Has anyone ever done this? Or are we talking about useful predictors?
I hear of psychologists using the vocabulary to assess the level of
as well as intelligence.
My apologies to your husband the psychologist
While this might be a relatively effective device for a homogeneous population
(and I doubt that it is really effective there)
Science (as opposed to opinion) disagrees.
in the midst of diversity, it is almost as poopy as dialect prejudice.
The presence of some folks in the population that are not represented in
the normative sample of the given test does not invalidate the test, it
only limits the interpretation.
My father ...told me about Leonard
Bloomfield's success in raising his childrens' IQs in a very short time by
simply drilling them in vocabulary.
Surely this group understands the fallacy of "teaching the test"?
I'd be surprised if there were
any significant differences in vocabulary size by discipline. Has any
research been done on this?
Oddly enough, yes.