Results 1 to 2 of 2

Math Help - stats: plz need help

  1. #1
    Junior Member
    Joined
    Mar 2007
    Posts
    63

    stats: plz need help

    A person scores 81 on a test of verbal ability and 6.4 on a test of quantitative ability. For the verbal ability test, the mean for people in general is 50 and the standard deviation is 20. For the quantitative ability test, the mean for people in general is 0 and the standard deviation is 5. Which is this person’s stronger ability: verbal or quantitative? Explain your answer to a person who has never had a course in statistics.
    Last edited by harry; September 12th 2007 at 02:30 PM.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Aug 2007
    From
    USA
    Posts
    3,111
    Thanks
    2
    Quote Originally Posted by harry View Post
    A person scores 81 on a test of verbal ability and 6.4 on a test of quantitative ability. For the verbal ability test, the mean for people in general is 50 and the standard deviation is 20. For the quantitative ability test, the mean for people in general is 0 and the standard deviation is 5. Which is this personís stronger ability: verbal or quantitative? Explain your answer to a person who has never had a course in statistics.
    Well, person who never has had statistics, you are going to have to learn one word. You may heave heard it before in a different context. I submit to you NORMALIZE.

    In this case, it means to invent a comparative measure so that different types of scores can be compared. Fortunately, the statistics wizards have done it already. I like to describe it to persons who never have had statistics as "How far off is it, compared to how far off it's supposed ot be?"

    Verbal

    Score 81
    Mean 50
    Standard Deviation 20
    How far off is it? 81 - 50 = 31
    Compare to how far off it is suppsed to be. 31/20 = 1.55
    Conclude: Well, then this person is 1.55 "supposed-to-be"s above where the average Joe is.

    Quantitative

    Score 6.4
    Mean 0
    Standard Deviation 5
    How far off is it? 6.4 - 0 = 6.4
    Compare to how far off it is suppsed to be. 6.4/5 = 1.28
    Conclude: Well, then this person is 1.28 "supposed-to-be"s above where the average Joe is.

    That's about it. Compare 1.55 to 1.28 and answer the question.

    You may find more technical terms, such as z-score, Normal Deviation, something like that, but I promised that you would have to learn only one word, so I'll leave it at that. There might even be a formula sitting about, somehting like \frac{x-\mu}{\sigma}, but again, I don't want to muddy the waters.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Stats
    Posted in the Statistics Forum
    Replies: 1
    Last Post: October 14th 2009, 02:45 PM
  2. Stats
    Posted in the Advanced Statistics Forum
    Replies: 4
    Last Post: August 9th 2009, 09:07 PM
  3. Stats
    Posted in the Advanced Statistics Forum
    Replies: 2
    Last Post: June 27th 2009, 01:02 AM
  4. STATS HELP!
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: October 5th 2008, 06:02 AM
  5. stats
    Posted in the Advanced Statistics Forum
    Replies: 4
    Last Post: December 31st 2007, 10:23 AM

Search Tags


/mathhelpforum @mathhelpforum