IQ tests and theory trends: Google Ngram visualizations

This past week I read a very intriguing article in the New York Times about a new data visualization tool offered by Google-- the Google Books Ngram Viewer. I then ran across a legal blog post where someone had investigated trends in different law terms...and I couldn't help myself but to give it a try.

As described by Robert Ambrogi at the legal blog:

"Using data drawn from the millions of books it has digitized covering the years 1500 to 2008, it lets you see and compare the frequency of words and phrases as they were used in books over a span of years or centuries. As Google puts it: “The Ngram Viewer lets you graph and compare phrases from these datasets over time, showing how their usage has waxed and waned over the years.”

I first had to experiment with how the entered terms worked. The terms are case sensitive. I checked each phrase with a variety of permutations to maximum the "hit rate"...and then ran some phrases together to ascertain and compare trends.

Below are my results with a few comments--the data tend to speak for themselves. I found that most of what I searched for did not emerge until after 1940...so that is where each graph starts. It is also important to note that the graphs only go up thru 2008...it would be nice to see the graphs up today

Cool stuff. Double click on each graph to enlarge.

This chart suggests that the cognitive ability domains of Gv (Visual Processing), Ga (Auditory Processing), and Processing Speed (Gs) have become hotter topics than Gf (Fluid Intelligence), Gc (Crystallized Intelligence), Gsm (Short term Memory), and Glr (Long term Retrieval). Interesting.

One very clear observation. Among the non-Wechsler intelligence batteries, the Stanford Binet has dropped dramatically over time, while the "newbies" on the IQ testing block (WJ, DAS, KABC, CAS) have made been the focus of more writing since 1990. Note, "Wechsler Intelligence", when included, is the clear winner across time. I left it out so the trends for the "other" batteries would be more distinct.

As I have written about many times, contemporary Cattell-Horn-Carroll (CHC) intelligence theory has become the consensus theory of intelligence. This interesting graph supports this conclusion, especially from 1997 to 2008. Also, if one clicks on the search term in the summary table, one is taken to a page of the Google books that included the term. Click here to see example for CHC theory.

I think many of the trends noted above are due to emergence of Gf-Gc theory to CHC theory with the publication of the 1989 WJ-R. I've written about this critical theory-to-practice birth period here and here.

- iPost using BlogPress from my Kevin McGrew's iPad

intelligence IQ tests IQ scores CHC theory Cattell-Horn-Carroll human cognitive abilities psychology school psychology individual differences cognitive psychology neuropsychology special education educational psychology psychometrics psychological assessment psychological measurement IQs Corner neuroscience neurocognitive cognitive abilities cognition Woodcock Johnson PASS CAS Wechsler Intelligence Batteries Kaufman Assessment Battery Differential Ability Scales Gardner multiple intelligences Sternberg Triarchic theory

IQ test battery publication timeline: Atkins MR/ID Flynn Effect cheat sheet

As I've become involved in consulting on Atkins MR/ID death penalty cases, a frequent topic raised is that of norm obsolescence (aka, the Flynn Effect). When talking with others I often have trouble spitting out the exact date of publication of the various revisions of tests, as I keep track of more than just the Wechsler batteries (which are the primary IQ tests in Atkins reports). I often wonder if others question my expertise...but most don't realize that there are more IQ batteries out there than just the Wechsler adult battery....and, in particular, a large number of child normed batteries and other batteries spanning childhood and adulthood. Thus, I decided to put together a cheat sheet for myself..one that I could print and have in my files. I put it together in the form of a simple IQ battery publication timeline. Below is an image of the figure. Double click on it to enlarge.

An important point to understand is that when serious discussions start focusing on the Flynn effect in trial's, most often the test publication date is NOT used in the calculation of how obsolete a set of test norms are. Instead, the best estimate of the year the test was normed/standardized is used, which is not included in this figure (you will need to locate this information). For example, the WAIS-R was published in 1981...but the manual states that the norming occurred from May 1976 to May 1980. Thus, in most Flynn effect discussions in court cases, the date of 1978 (middle of the norming period) is typically used. This makes recall of this information difficult for experts who track all the major individually administered IQ batteries.

Hope this helpful...if nothing else...you must admit that it is pretty :)  Click on image to view





- iPost using BlogPress from my Kevin McGrew's iPad

intelligence intelligence testing Atkins cases ICDP blog psychology school psychology neuropsychology Forensic psychology criminal psychology criminal justice death penalty capital punishment ABA IQ tests IQ scores adaptive behavior AAIDD mental retardation intellectual disability Flynn effect

Differential Ability Scales-2nd edition: One more in the CHC column

Kudos to Colin Elliott for the recent publication of the second edition of the Differential Ability Scales (DAS-2). As I wrote about the DAS in my 1997 CHC broad-narrow analysis of all major intelligence batteries (in Flanagan et al.'s, 1997 CIA book), I considered it to be the second most comprehensive battery of CHC abilities...the first, of course, being the deliberately CHC-designed WJ-R and WJ -III (obligatory conflict of interest - I'm a coauthor of the WJ III). I'm not surprised to see that it has now joined the growing crowd (see my CHC bandwagon post) of deliberately CHC-designed intelligence batteries, as it was, IMHO, the next-best instrument (from a CHC perspective) at the time (1997).

As usual, check out the Willis and Dumont web site for additional DAS-2 related information.

I'd love to see a copy. Hint...hint......is anyone from Psych. Corp. listening? Don't you like the free publicity I just gave the DAS-2? I'd sure love a complimentary copy to examine.





Technorati Tags: psychology, educational psychology, school psychology, neuropsychology, IQ, intelligence, IQ test, IQ score, DAS, DAS-2, Differential Ability Scales, CHC theory

Powered by ScribeFire.

CHC intelligence theory and DAS and WJ III

The following article, which provides support for the CHC Theory of Cognitive Abilities, as well providing important information on the CHC classifications of the individual tests from the DAS and WJ III intelligence batteries, was recently published in Psychology in the Schools.

Given my obvious conflict of interest (co-author of WJ III), as well as the credit attributed to me in the recognition of CHC theory in the article (I'm humbled), I'm not going to comment on the contents. Read and make your own judgments.

• Sanders, S., McIntosh, D., Dunham, M., Rothlisberg, B. Finch, H. (2007). Joint confirmatory factor analysis of the Differential Ability Scales and the Woodcock-Johnson Tests of Cognitive Abilities--Third Edition. Psychology in the Schools, Vol. 44(2), 119-138 (click here to view)

Abstract

• This study examined the underlying constructs measured by the Differential Ability Scales (DAS; C.D. Elliott, 1990a) as they relate to the Cattell-Horn-Carroll (CHC) Theory (K.S. McGrew, 1997) of cognitive abilities. The DAS and Woodcock-Johnson Tests of Cognitive Abilities (WJIII COG; R.W.Woodcock, K.S. McGrew, N. Mather, 2001) were administered to 131 children in grades 3 through 5 who took part in a concurrent validity study included in the Woodcock- Johnson Tests of Cognitive Abilities, Third Edition, technical manual (K.S. McGrew R.W. Woodcock, 2001). Confirmatory factor analyses using maximum likelihood estimation were conducted with the AMOS 5.0 (J.L. Arbuckle, 2001) statistical program to evaluate three models of increasing complexity, to compare how well each fit the data set, and to identify the one that best described the underlying constructs measured by the DAS. Results suggested that the synthesized Three-Stratum CHC Model provided the most parsimonious representation among the three models tested.

Technorati Tags: psychology, school psychology, educational psychology, neuropsychology, intelligence, IQ, IQ tests, IQ scores, CHC theory, Cattell-Horn-Carroll, Gf-Gc, DAS, WJ III, Differential Ability Scales, Woodcock-Johnson

powered by performancing firefox

CHC study of WJ-R and DAS in preschool sample

Tusing, M. B., & Ford, L. (2004). Examining preschool cognitive abilities using a CHC framework. International Journal of Testing, 4(2), 91-114.


Abstract

• Although there has been a substantial growth in the number of published studies examining tests of cognitive abilities and using contemporary theories of cognitive abilities, to date none have done so with preschool cognitive tests. In this study the relation between cognitive ability measures for young children and Cattell–Horn–Carroll (CHC) theory is examined. Tests and subtests from the Differential Ability Scales: Upper Preschool Level and the Woodcock–Johnson Tests of Cognitive Ability–Revised with a sample of 158 children between 4 and 5 years of age were used in a series of joint factor analyses. Although a series of models were explored, the model representative of the CHC theory of cognitive abilities was best supported by the data. This provides evidence for a greater differentiation of young children’s cognitive abilities than are typically interpreted. Results are discussed with regard to understanding the link between contemporary theories of intelligence and young children’s cognitive abilities, as well as implications for intellectual assessment practices with young children.

Additional comments (by study authors) in discussion section

• "The notion that young children's cognitive abilities are best conceptualized as dichotomous is dismissed."

• "In this study, five broad ability factors were reliably identified: Gc intelligence, Glr, Gsm, Ga, and a fifth factor that we originally referred to as nonverbal ability."

• "Evidence for the differentiation of the Gy factor represented in Carroll's three-stratum theory into two distinct broad abilities (Glr and Gsm) and the identification of visual-memory as a narrow ability under Gv provide further support for McGrew and Flanagan's (McGrew, 1997; McGrew & Flanagan, 1998) integration of three-stratum theory and Gf--Gc theory into CHC theory."

• "Two broad ability factors thought to be represented by the subtests included in this study did not significantly distinguish themselves in this sample, namely, Gf and Gq. It is possible that these broad ability factors are not able to be distinguishedcfrom other broad abilities with samples of young children, as their loadingscon the broad ability factor with which they were identified were significant.cHowever, failure to identify the specific broad abilities of Gf and Gq is more likely due to a lack of additional tasks measuring the same abilities."

Differentail Ability Scales (DAS) and CHC theory - a research study

AN Dissertation Abstract: 2004-99024-119. AU Sanders, Sarah J.

TI A joint confirmatory factor analysis of the differential ability scales and the Woodcock-Johnson tests of cognitive abilities - third edition.

SO Dissertation Abstracts International: Section B: The Sciences & Engineering. Vol 65(6-B), 2004, 3218. US: Univ Microfilms International.

Abstract

• Human cognitive ability has been a popular area of research that has developed over the past century. Theories and measures of ability have ranged from very simplistic definitions and tests, such as a global intelligence construct (IQ) and single sensory/motor tests to highly complex multiple ability theoretical conceptualizations with corresponding batteries of tests. Additionally, the mandated use of intellectual measures for guiding educational and diagnostic decisions has led to a steady increase in the development of cognitive batteries and the need for a clearer understanding of what constructs these tests measure. The purpose of this study was to investigate the Differential Ability Scales (DAS; Elliott, 1990a), a standardized measure of cognitive ability, in relation to the Cattell-Horn-Carroll (CHC) theory of cognitive abilities. The CHC theory is a hierarchical three-tiered taxonomy consisting of has an overall general ability (Stratum III), with several broad abilities (Stratum II) that consist of numerous narrow abilities (Stratum I). This was accomplished by analyzing the DAS in conjunction with the Woodcock-Johnson Tests of Cognitive Abilities-Third Edition (WJ-III COG; Woodcock, McGrew, & Mather, 2001b), a contemporary cognitive ability measure developed based on the CHC theory. A group of 133 school-aged children were administered the DAS and WJ-III COG. Several variations of the CHC model were examined to determine which provided the best representation of the underlying CHC constructs measured by the DAS. Results of these confirmatory factor analyses supported the interpretation of the DAS from a CHC theoretical perspective. Moreover, this study confirmed that the DAS contains relatively strong measures of six of the CHC second-stratum abilities. Although a two-stratum CHC model provided the best statistical representation, results suggested that the complete, hierarchical three-stratum CHC model also should be considered a tenable solution. Specifically, these results confirmed that most of the CHC abilities (Gc, Gv, Glr, Gs, Gf, and Gsm) are measured on the DAS cognitive battery, with each of the DAS subtests representing primary indicators (Strata I narrow abilities) of these broad ability domains.