You probably heard before of the "Flynn Effect", the phenomenon first described by James Flynn which states that every new generation has an average IQ higher than the one before and as a consequence, with every new generation, we make new tests that fit the latter.

Now, the above is what the objective facts are and all of what comes after is an explanation of my reasoning and what the implications of the "effect" are according to my own subjective opinion, so you are allowed and encouraged to challenge anything I say below.

What this phenomenon means to me is twofold; First, I think that it's impossible that on average, our children are smarter than us as there is no reason for that to happen and biologically, no species can evolve that fast and the genetic differences between two successive generation is completely negligible. Second, by assuming the first proposition, there is, in my opinion, only one possible explanation for the Flynn Effect and that is that the accelerating dominance and importance of standardized testing in our education system worldwide leads pupils to score higher each time as they become more accustomed to that specific way of testing which leads to obvious conclusion that the IQ test is very far from being completely reliable as it's sole duty is to test how good said person is at taking tests.

There are probably multiple flaws from my logic but however many flaws one can find, this effect will always lead, in my opinion, to the conclusion that the IQ test is not greatly reliable at all.

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    Welcome to Skeptics! According to the FAQ, Skeptics.SE is for researching the evidence behind the claims you hear or read. This question doesn't appear to have any doubtful claims made by others to investigate. Please edit it to reference a notable claim. – Oddthinking Apr 1 '13 at 0:53
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    We have already had some answers talking about the Flynn Effect, where they point to papers that attribute the result to better nutrition, healthcare, smaller families, (and better literacy) which reveals a flaw in your logic. – Oddthinking Apr 1 '13 at 0:55
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    If your doubtful of IQ tests, please refer to this question as well: skeptics.stackexchange.com/questions/2758/… – Larian LeQuella Apr 1 '13 at 1:54
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    @Zoshi, just because you "think it it's impossible that on average ..." doesn't mean it really is impossible. Just because you personally can't instantly see a reason for something doesn't mean that something doesn't happen. What an arrogant attitude. If scientists had such an attitude, many would reject quantum mechanics and relativity due to their counter intuitive nature. – Kenshin Apr 1 '13 at 8:07
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    "I think that it's impossible that on average, our children are smarter than us as there is no reason for that to happen and biologically, no species can evolve that fast and the genetic differences between two successive generation" — you're completely ignoring possible simple explanation, like the fact that it was studied 1932-1978, thus comparing generations with vast amount of people who grew up in poverty and malnourished, with generations better nourished and with better healthcare. – vartec Jul 13 '15 at 1:56

Flynn effect does not discredit the notion of IQ tests since the effect has several drawbacks if studied on the basis of IQ test validation studies such as "sample sizes tend to be small; the earlier and later versions of the same test may differ significantly in format or content (e.g., Kaufman, 2010); there may be significant order effects; many tests are never re-normed and therefore lie beyond the reach of this method; and direct within-examinee comparisons have not been made for many tests even if the tests have been re-normed. In addition, validation studies rely on group-level data and presuppose a representative normative basis for the derivation of a standardized IQ score." per a meta-analytic study 'The Flynn Effect: A Meta-analysis' by Lisa Trahan et.al. in 2014.

The “Flynn effect” refers to the observed rise over time in standardized intelligence test scores, documented by Flynn in a study on intelligence quotient (IQ) score gains in the standardization samples of successive versions of Stanford-Binet and Wechsler intelligence tests. Flynn’s study revealed a 13.8-point increase in IQ scores between 1932 and 1978, amounting to a 0.3-point increase per year, or approximately 3 points per decade. More recently, the Flynn effect was supported by calculations of IQ score gains between 1972 and 2006 for different normative versions of the Stanford-Binet (SB), Wechsler Adult Intelligence Scale (WAIS), and Wechsler Intelligence Scale for Children (WISC). The average increase in IQ scores per year was 0.31, which was consistent with Flynn’s earlier findings.

This meta-analytic study in 2014 shows that it is advisable to correct IQ scores for the Flynn effect such as in high stakes decisions in the United States for determination of intellectual disability in capital punishment cases. Also, researchers concluded that the study results supported previous estimates of the Flynn effect and its robustness across different age groups, measures, samples, and levels of performance. The overall Flynn effect of 2.31 produced by this meta-analysis was lower than Flynn’s value of 3.11 in a 2009 study and Fletcher et al.’s value of 2.80 in a 2010 study.

Conclusions: For the present, the need to correct IQ test scores for norms obsolescence in high stakes decision-making is abundantly clear. At average levels of IQ, a score difference of 95 and 98 is not critical. However, in capital punishment cases, life and death may reside on a 3-point difference of 76 versus 73, or 71 versus 68. These findings are consistent with previous research and with the argument that it is feasible and advisable to correct IQ scores for the Flynn effect in high stakes decisions.

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