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Homework Help: Interpreting this Statistics question

  1. Jun 1, 2013 #1
    1. The problem statement, all variables and given/known data

    On p. 13, they present and discuss Table 1, summary scores for the test periods. At the bottom of the first column, they say that the "fall CBM WIF is 0.85 standard deviations below the mean." What mean are they referring to? What is the value of the mean?

    2. Relevant equations

    None needed.

    3. The attempt at a solution

    Here is the pdf: http://casenex.com/casenex/cecReadings/monitoringEarly.pdf
    (Go to page 13 on the paper)

    You may have to read several pages to get the context. I would be extremely grateful if someone helped me, I've been stuck wondering what mean they are talking to for an hour already. I thought I was missing something along the way, and I so I've re-read it again and again.

    The data collectors take a measurement of the fall CBM WIF measures once in fall and once in spring along with other criterion measures. Then they assess the two CBM measures for 20 weeks as well.

    I thought that there are two means being referred to in the second column on page 13. The average of the two fall CBM measurements and the two spring CBM measurements.
    Last edited: Jun 1, 2013
  2. jcsd
  3. Jun 2, 2013 #2

    Simon Bridge

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    They tell you on that page:
    Means and standard deviations for these scores and for the criterion
    variables are shown in Table 1.

    -- p13​

    ... the values in the table are mean and standard deviation.
  4. Jun 2, 2013 #3
    Would the mean be 10.11 and 29.72?
    Fall CBM WIF score: 10.11 - 0.85(9.26)
    Spring CBM WIF score: 29.72 - 1.24(19.96)
  5. Jun 2, 2013 #4

    Simon Bridge

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    I only looked long enough to read the description of what the table values were.
    From memory, the first part of the table had headings X and SDX or somesuch.
    From the text on page 13, I figure the X column is all means and the SDX column is all standard deviations on the X value immediately to it's left.

    If your numbers reflect that then the answer is "yes" and if they do not then the answer is "no".

    Could it be that you don't know how to use the data in the article?
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