# brain sizes: Einstein's and women's

Jet thatjetnospam at yahoo.com
Wed Jul 17 22:12:15 EST 2002

```
John Knight wrote:
>
> "Jet" <thatjetnospam at yahoo.com> wrote in message
> news:3D35D71A.36E73264 at yahoo.com...
> >
> >
> > John Knight wrote:
> > >
> > > "Jet" <thatjetnospam at yahoo.com> wrote in message
> > > news:3D353D8F.8A736C4B at yahoo.com...
> > > >
> > > >
> > > > Bob LeChevalier wrote:
> > > > >
> > > > > "John Knight" <johnknight at usa.com> wrote:
> > > > > >Believe me, Parse, you don't need algebra or calculus to calculate
> the
> > > > > >statistical average for American girls in TIMSS math.  Even
> > > for
> > > > > >guesses doesn't require anything but some very basic probability
> > > theory.
> > > > > >
> > > > > >It's as simple as this:
> > > > > >
> > > > > >If you're asked a question which has four multiple choice answers,
> and
> > > you
> > > > > >haven't got a clue what the answer is, what is the probability of
> > > getting a
> > > > > >correct answer?  Since you have once chance in four of getting the
> > > right
> > > > > >answer, your probability is 0.25.  If you guess on two questions,
> your
> > > > > >probability is .5, and three it's .75, and four, it's 1.0.
> > > > > >
> > > > > >In other words, over the long run, or over millions of test takers,
> > > guessing
> > > > > >on such a question will yield 25% correct answers, or conversely,
> every
> > > > > >fourth answer will be correct.
> > > > >
> > > > > This makes the assumption that those who know nothing guess
> randomly.
> > > IN
> > > > > reality, we don't know that people guess randomly when faced with a
> test
> > > > > question they do not understand.  Indeed, we know that they do not.
> > > > >
> > >
> > > Wrong.  Dead wrong.  You could make that argument about one question,
> but
> > > when the pattern is repeated over and over again, then you can detect a
> > > pattern:  American girls scored lower on many questions than if they'd
> just
> > > guessed because they didn't have a clue about what the answer was.
> >
> > Do you? Give us the answer, and the explanation, so we know you are not
> > guessing.
> >
> >   Many of
> > > all], which means you're nuts to even hint that "Indeed, we know that
> they
> > > do not"  "guess randomly".
> > >
> > > The ONLY time you could apply that argument is when a large percentage
> of
> > > them answered correctly, but even then, if 0% failed to respond at all,
> then
> > > some of them HAD to guess.
> >
> > Well, that's a reasonable assumption, but so what? Some people probably
> > guess on every multiple choice question on ever test.
>
> You and I agree.  LeChevalier is an idiot.

No, he is not, you are.

He said, and I quote:  "we don't
> know that people guess randomly when faced with a test question they do not
> understand.  Indeed, we know that they do not".

It would make sense that in general, people will guess randomly as a
last resort.

>
> This is not the stupidest thing he's ever said.  And he'll deny even said it
> as time goes by.  But only a real moron "thinks" like this.
> >
> > >
> > > > > But the assumption becomes totally meaningless if in fact they know
> > > > > SOMETHING.  If 100% of them know something, but not enough to solve
> the
> > > > > problem, then it is quite plausible that 100% of them will get the
> > > > > wrong.  Thus someone knowing Newtonian physics perfectly will get
> the
> > > wrong
> > > > > answer on a question that uses special relativity theory.  A good
> test
> > > > > designer will know that the Newtonian approximation is a likely
> error,
> > > and
> > > > > will include that answer among the incorrect alternatives.
> > > >
> > > > Then the article makes the shockingly stupid conclusion that NONE of
> the
> > > > girls who got the answer right understood the problem!
> > > >
> > >
> > > If guessing on a multiple choice question would yield 25% correct, but
> > > American girls only got 5% correct, then how would YOU calculate how
> many of
> > > them understood the problem?
> >
> > Maybe 95% of the girls didn't understand the question, 5% did. Um, duh.
>
> You don't seem to understand the point either.  If *all* students just
> *guessed* on a four part multiple choice question, and didn't have a clue
> about what the answer was, they would have gotten 25% of them correct just
> by chance.

Yes, so it seems that they did not all guess randomly.

>
> The only way for them to get less than 25% correct would be to know
> something about the problem and select the wrong answer on purpose, or to
> have the wrong information in the first place.

Or to think they know the answer, and be wrong. Like you are most of the
time.

>
> If 30% of them got it correct, this doesn't mean that 30% of them knew the
> answer.  If they didn't have the wrong information, or didn't make an error,
> then of the 30% who got it correct, 23% would have gotten it correct because
> they guessed, and only 7% would have gotten it correct because they
> understood the problem [ x = total guesses, 0.25x = correct guesses 0.75x =
> wrong guesses = 70%, x = .93, 0.25x = .23 = correct guesses, correct total
> answers of 30% - 23% correct guesses = 7% (those who knew the problem)].

The above is utter nonsense. If we figure 0.25x = 30%, then x= 1.2! X
can't be both .93 and 1.2.

How does it feel to have a woman mop the floor up with you WRT math?

>
> >
> > >
> > > > >
> > > > > >No algebra.  No calculus.  A bit of probability theory, and you
> > > know
> > > > > >that 25% of all students will get the correct answer if they only
> > > *guess* on
> > > > > >a four part multiple choice question.
> > > > >
> > > > > But you have no evidence that any kid "guessed" on any problem.
> > > > >
> > > > > >Now here's the hard part:
> > > > > >
> > > > > >Question H04 on TIMSS had four multiple choice answers, so you
> would
> > > think
> > > > > >that no country or age group or race or sex would answer less than
> 25%
> > > of
> > > > > >them correct, right?
> >
> > This would only make sense if everyone in the group knew they didn't
> > know, and just started guessing.
> >
>
> Which was the case for many of the questions that American girls answered.
> You can't score that low, consistently, if you know something about the
> subject

Why not? BTW, do you know the answer?
>
> > > > >
> > > > > Wrong.  I would think that if the question were difficult and well
> > > designed,
> > > > > that this would be quite possible.
> > > > >
> > > > > >How do you think that's possible?
> > > > > >
> > > > > >You can probably figure this out with no knowledge of algebra or
> > > calculus,
> > > > > >and you already know all the probability theory that might be
> needed,
> > > so
> > > > > >what is your explanation?
> > > > >
> > > > > I've given an explanation, and mine explains how on question D12,
> both
> > > boys
> > > > > and girls in the US scored less than 17% and South Africans scored
> only
> > > 6.4%
> > > > > correct.
> > > >
> > > > Isn't it odd that someone who is harping on math ability doesn't seem
> to
> > > > realize that 17 and 6 are both lower than 25? :)
> > > >
> > > > J
> > >
> > > What's your point, J?
> >
> > My point is that you illustrate the saying, "Figures don't lie, but
> > liars sure can figure."
> >
> > You figure because American girls got a score of 22.something correct on
> > one test question on one test, that there is no such thing as "gender
> > equality".
> >
>
> No.  I figure because American girls consistently scored lower than if
> they'd just guessed on a number of problems, not just one, and because this
> is a pattern that's repeated in many other tests, that they were either
> misinformed in the classroom, or didn't believe what they were taught and
> went with "intuition" instead of facts (or a combination).
>
> American boys didn't do that much better, btw, which is another thing that I
> figure.

Why? Intuition? LOL.

>
> >  Who exactly do you think made the point that getting
> > > 17% correct on a four part multiple guess problem is a lower score than
> if
> > > everyone just guessed?
> >
> > You?
> >
> > >
> > > What part of that don't you understand (other than the typical and
> > > infinitely STUPID statement by lojbab that no students guessed)?
> >
> > He never made that statement.
> >
> > J
> >
>
> And I quote:  "we don't know that people guess randomly when faced with a
> test question they do not understand.  Indeed, we know that they do not".
>
> Do you agree with that statement, J?

I can't know for sure, but my guess is that most people use random
guessing is a last resort. So, in general, I do.

J

>
> John Knight

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