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Homework Help: Basic statistics question

  1. Sep 8, 2011 #1
    1. The problem statement, all variables and given/known data
    A Fisher presents the following data, which give the logarithm to the base 10 of the volume occupied by algal cells on successive days, taken over a period for which the relative growth rate is approximately constant.

    Day 1 = 3.592, Day 2 = 3.823, Day 3 = 4.174, Day 4 = 4.532, Day 5 = 4.956, Day 6 = 5.163, Day 7 = 5.495 Day 8 = 5.602, Day 9 = 6.087

    Plot y against x. Do you think that the logarithmic transformation is appropriate? If so, why? Calculate and interpret the sample co-relation coefficient . By the method of least squares, fit log = alpha + betax to the n = 9 data points.

    3. The attempt at a solution

    I don't know what they mean by "transformation is appropriate". What am I supposed to do here? I also don't get what they want me to do with the calculation. Is X the n here? Plug in the values and then calculate it?

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

    Tukey discusses the relationship between the vapor pressure of B-trimethyl -borazole ( ym in millimeters of mercury) and temperature ( x, in C )

    X= 13 y= 2.9 X=56.1 y=51.4 (It's a list with 4 columns. 8 rows ))
    X=19.5 y= 5.1 X64.4 y=74.5

    Plot y against x. How can we straighten this plot? Try various transformations.

    3. The attempt at a solution

    Ok, straighten what, how? To it's a straight horizontal line? so I have to compare the X and Y values and find a pattern ? Like, X=4 y=2.. then just use square root for all the y values?
  2. jcsd
  3. Sep 8, 2011 #2


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    have you plotted you plotted the data? if so what do you see?
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