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"Test-Score-Differences Fallacy 1: Nonfixedness Proves Malleability This fallacy uses evidence of any fluctuation or growth in the mental functioning of indivi

by Matti 17y ago

"Test-Score-Differences Fallacy 1: Nonfixedness Proves Malleability This fallacy uses evidence of any fluctuation or growth in the mental functioning of individuals as if it were proof that their rates of growth can be changed intentionally. IQ level is not made malleable by any means yet devised (Brody, 1996), ..." - Linda Gottfredson, Logical fallacies used to dismiss the evidence on intelligence testing http://www.udel.edu/educ/gottfredson/reprints/2009fallacies.pdf http://www.udel.edu/educ/gottfredson/reprints/2009fallacies.... (PDF page 24)

Alex3917 17y ago
So you are saying that iodine deficiency does not cause a decrease in IQ?
- crystalis 17y ago
  The traditional view is similar to IQ as an empty glass. You can fill it up to the top, but once you're there, you've maxed out on IQ itself. Different people have differently sized glasses, and there are many things that clearly affect the rate or amount of fill, just as there are many things that affect height. However, there are few things that indicate that they are increasing the potential IQ. Losing a tire in my car won't make me lose any horsepower, but it's not going to be the same ride.
  - tokenadult 17y ago
    The traditional view is similar to IQ as an empty glass. Actually, the view of behavioral geneticists, including those with whom I have a weekly discussion of current research, http://www.psych.umn.edu/courses/fall09/mcguem/psy8935/default.htm http://www.psych.umn.edu/courses/fall09/mcguem/psy8935/defau... is that each individual has a "reaction surface," a range of possible behavioral responses genetically endowed for that individual depending on what environmental influences that individual encounters. NO ONE active in the field of behavorial genetics claims to have proved that many individuals today have maxed out their potential for intelligent behavior. There may be (as yet unknown) interventions that could massively change IQ at the individual level.
    - rkts 17y ago
      No one has proved that technology won't one day make everyone grow to 6 feet and live 200 years. In fact that could quite plausibly happen. But you'd still be a fool to count on it.
- deleted 17y ago
  [deleted]
rauljara 17y ago
No, the fact that IQ can change does not prove that it can be intentionally changed. Head start, the increases in IQ that African Americans experienced when they moved out the segregated South, the Flynn effect, etc. also do not definitively prove that IQ can be intentionally changed. All they do is strongly suggest it. However, I have yet to see any evidence that would strongly suggest that IQ is impervious to change that is anywhere near as convincing as the above. Even identical twin studies (which have inherent problems with them) suggest that a large percentage of IQ is determined by the environment. Definitive proof is very hard to come by when it comes to human behavior. Just because something has not been definitively proved does not mean it is wrong.
- yummyfajitas 17y ago
  Head start only raises scores on IQ tests in early childhood. The effect vanishes by the end of the first grade. This is most likely because children in Head Start become more familiar with IQ test style problems and a testing environment. In short, Head Start (presumably unintentionally) teaches the test. http://www.eric.ed.gov/ERICDocs/data/ericdocs2sql/content_storage_01/0000019b/80/2f/03/6f.pdf http://www.eric.ed.gov/ERICDocs/data/ericdocs2sql/content_st... (Scroll to page 65)
- tokenadult 17y ago
  Even identical twin studies (which have inherent problems with them) suggest that a large percentage of IQ is determined by the environment. Yes, this is a correct statement. The design of studies to determine a numerical figure for the pre-Mendelian concept of "heritability" can only show a MINIMUM influence of environment, and the minimum influence of environment on IQ is fairly large. Most heritability studies are, by their nature, naturalistic rather than experimental studies and prove nothing about what degree of malleability (a separate issue anyway) might be found if an experimenter tried targeted environmental interventions. And, yes, there are monozygotic twins who are discordant for IQ, so there must be influences other than genes on IQ.
tokenadult 17y ago
I have read much of what Linda Gottfredson (and Nathan Brody, her cited authority on this issue) have written on IQ testing. But Gottfredson's statement doesn't prove that IQ scores can't change for an individual, but merely says that we aren't sure yet how consistently to bring about changes in individual IQ scores. IQ score changes are a consistently replicated observation by many researchers, and a curious psychologist might well apply some research to the issue of how those changes happen. IQ scores are sufficiently stable from one time of taking an IQ test to the next that most psychologists conclude that what is estimated by an IQ test can be regarded as a "trait" rather than a "state" of an individual test-taker. And yet IQ scores, especially in childhood, do vary over the course of a test-taker’s life, sometimes varying radically. Deviation IQ scoring was originally developed to make for more stability of scores over the course of childhood. Nonetheless, deviation IQs for children can also change considerably over the course of childhood (Pinneau 1961; Truch 1993, page 78; Howe 1998; Deary 2000, table 1.3). "Correlation studies of test scores provide actuarial data, applicable to group predictions. . . . Studies of individuals, on the other hand, may reveal large upward or downward shifts in test scores." (Anastasi & Urbina 1997 p. 326). For example, young people in the famous Lewis Terman longitudinal Genetic Studies of Genius (initial n=1,444 with n=643 in main study group) when tested at high school age (n=503) were found to have dropped 9 IQ points on average in Stanford-Binet IQ. More than two dozen children dropped by 15 IQ points and six by 25 points or more. Parents of those children reported no changes in their children or even that their children were getting brighter (Shurkin 1992, pp. 89-90). Terman observed a similar drop in IQ scores in his study group upon adult IQ testing (Shurkin 1992, pp. 147-150). Samuel R. Pinneau conducted a thorough review of the Berkeley Growth Study (1928-1946; initial n=61, n after eighteen years =40). Alice Moriarty was a Ph.D. researcher at the Menninger Foundation and describes in her book (1966) a number of case studies of longitudinal observations of children's IQ. She observed several subjects whose childhood IQ varied markedly over the course of childhood, and develops hypotheses about why those IQ changes occurred. Anastasi and Urbina (1997, p. 328) point out that childhood IQ scores are poorest at predicting subsequent IQ scores when taken at preschool age. Change in scores over the course of childhood shows that there are powerful environmental effects on IQ (Anastasi & Urbina 1997, p. 327) or perhaps that IQ scores in childhood are not reliable estimates of a child’s scholastic ability. REFERENCES Anastasi, Anne & Urbina, Susana (1997). Psychological Testing. Upper Saddle River, NJ: Prentice Hall. Deary, Ian J. (2000) Looking Down on Human Intelligence: From Psychometrics to the Brain. Oxford: Oxford University Press. Howe, Michael J. A. (1998). Can IQ Change?. The Psychologist, February 1998 pages 69-72. Moriarty, Alice E. (1966). Constancy and IQ Change: A Clinical View of Relationships between Tested IQ and Personality. Springfield, IL: Charles C. Thomas. Pinneau, Samuel R. (1961). Changes in Intelligence Quotient Infancy to Maturity: New Insights from the Berkeley Growth Study with Implications for the Stanford-Binet Scales and Applications to Professional Practice. Boston: Houghton Mifflin. Shurkin, Joel N. (1992). Terman's Kids: The Groundbreaking Study of How the Gifted Grow Up. Boston: Little, Brown. Truch, Steve (1993). The WISC-III(R) Companion: A Guide to Interpretation and Educational Intervention. Austin, TX: Pro-Ed.

by Matti 17y ago

Alex3917 17y ago

So you are saying that iodine deficiency does not cause a decrease in IQ?

crystalis 17y ago
The traditional view is similar to IQ as an empty glass. You can fill it up to the top, but once you're there, you've maxed out on IQ itself. Different people have differently sized glasses, and there are many things that clearly affect the rate or amount of fill, just as there are many things that affect height. However, there are few things that indicate that they are increasing the potential IQ. Losing a tire in my car won't make me lose any horsepower, but it's not going to be the same ride.
- tokenadult 17y ago
  The traditional view is similar to IQ as an empty glass. Actually, the view of behavioral geneticists, including those with whom I have a weekly discussion of current research, http://www.psych.umn.edu/courses/fall09/mcguem/psy8935/default.htm http://www.psych.umn.edu/courses/fall09/mcguem/psy8935/defau... is that each individual has a "reaction surface," a range of possible behavioral responses genetically endowed for that individual depending on what environmental influences that individual encounters. NO ONE active in the field of behavorial genetics claims to have proved that many individuals today have maxed out their potential for intelligent behavior. There may be (as yet unknown) interventions that could massively change IQ at the individual level.
  - rkts 17y ago
    No one has proved that technology won't one day make everyone grow to 6 feet and live 200 years. In fact that could quite plausibly happen. But you'd still be a fool to count on it.
deleted 17y ago
[deleted]

rauljara 17y ago

No, the fact that IQ can change does not prove that it can be intentionally changed. Head start, the increases in IQ that African Americans experienced when they moved out the segregated South, the Flynn effect, etc. also do not definitively prove that IQ can be intentionally changed. All they do is strongly suggest it. However, I have yet to see any evidence that would strongly suggest that IQ is impervious to change that is anywhere near as convincing as the above. Even identical twin studies (which have inherent problems with them) suggest that a large percentage of IQ is determined by the environment. Definitive proof is very hard to come by when it comes to human behavior. Just because something has not been definitively proved does not mean it is wrong.

yummyfajitas 17y ago
Head start only raises scores on IQ tests in early childhood. The effect vanishes by the end of the first grade. This is most likely because children in Head Start become more familiar with IQ test style problems and a testing environment. In short, Head Start (presumably unintentionally) teaches the test. http://www.eric.ed.gov/ERICDocs/data/ericdocs2sql/content_storage_01/0000019b/80/2f/03/6f.pdf http://www.eric.ed.gov/ERICDocs/data/ericdocs2sql/content_st... (Scroll to page 65)
tokenadult 17y ago
Even identical twin studies (which have inherent problems with them) suggest that a large percentage of IQ is determined by the environment. Yes, this is a correct statement. The design of studies to determine a numerical figure for the pre-Mendelian concept of "heritability" can only show a MINIMUM influence of environment, and the minimum influence of environment on IQ is fairly large. Most heritability studies are, by their nature, naturalistic rather than experimental studies and prove nothing about what degree of malleability (a separate issue anyway) might be found if an experimenter tried targeted environmental interventions. And, yes, there are monozygotic twins who are discordant for IQ, so there must be influences other than genes on IQ.

tokenadult 17y ago

I have read much of what Linda Gottfredson (and Nathan Brody, her cited authority on this issue) have written on IQ testing. But Gottfredson's statement doesn't prove that IQ scores can't change for an individual, but merely says that we aren't sure yet how consistently to bring about changes in individual IQ scores. IQ score changes are a consistently replicated observation by many researchers, and a curious psychologist might well apply some research to the issue of how those changes happen. IQ scores are sufficiently stable from one time of taking an IQ test to the next that most psychologists conclude that what is estimated by an IQ test can be regarded as a "trait" rather than a "state" of an individual test-taker. And yet IQ scores, especially in childhood, do vary over the course of a test-taker’s life, sometimes varying radically. Deviation IQ scoring was originally developed to make for more stability of scores over the course of childhood. Nonetheless, deviation IQs for children can also change considerably over the course of childhood (Pinneau 1961; Truch 1993, page 78; Howe 1998; Deary 2000, table 1.3). "Correlation studies of test scores provide actuarial data, applicable to group predictions. . . . Studies of individuals, on the other hand, may reveal large upward or downward shifts in test scores." (Anastasi & Urbina 1997 p. 326). For example, young people in the famous Lewis Terman longitudinal Genetic Studies of Genius (initial n=1,444 with n=643 in main study group) when tested at high school age (n=503) were found to have dropped 9 IQ points on average in Stanford-Binet IQ. More than two dozen children dropped by 15 IQ points and six by 25 points or more. Parents of those children reported no changes in their children or even that their children were getting brighter (Shurkin 1992, pp. 89-90). Terman observed a similar drop in IQ scores in his study group upon adult IQ testing (Shurkin 1992, pp. 147-150). Samuel R. Pinneau conducted a thorough review of the Berkeley Growth Study (1928-1946; initial n=61, n after eighteen years =40). Alice Moriarty was a Ph.D. researcher at the Menninger Foundation and describes in her book (1966) a number of case studies of longitudinal observations of children's IQ. She observed several subjects whose childhood IQ varied markedly over the course of childhood, and develops hypotheses about why those IQ changes occurred. Anastasi and Urbina (1997, p. 328) point out that childhood IQ scores are poorest at predicting subsequent IQ scores when taken at preschool age. Change in scores over the course of childhood shows that there are powerful environmental effects on IQ (Anastasi & Urbina 1997, p. 327) or perhaps that IQ scores in childhood are not reliable estimates of a child’s scholastic ability. REFERENCES Anastasi, Anne & Urbina, Susana (1997). Psychological Testing. Upper Saddle River, NJ: Prentice Hall. Deary, Ian J. (2000) Looking Down on Human Intelligence: From Psychometrics to the Brain. Oxford: Oxford University Press. Howe, Michael J. A. (1998). Can IQ Change?. The Psychologist, February 1998 pages 69-72. Moriarty, Alice E. (1966). Constancy and IQ Change: A Clinical View of Relationships between Tested IQ and Personality. Springfield, IL: Charles C. Thomas. Pinneau, Samuel R. (1961). Changes in Intelligence Quotient Infancy to Maturity: New Insights from the Berkeley Growth Study with Implications for the Stanford-Binet Scales and Applications to Professional Practice. Boston: Houghton Mifflin. Shurkin, Joel N. (1992). Terman's Kids: The Groundbreaking Study of How the Gifted Grow Up. Boston: Little, Brown. Truch, Steve (1993). The WISC-III(R) Companion: A Guide to Interpretation and Educational Intervention. Austin, TX: Pro-Ed.