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Thread: Finding the p value

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    Finding the p value




    I am taking a statistics class, and i have some problems Understanding a formula.

    The formula in question is like this:

    p-value=2P(T>|t_obs,beta_i|)

    I have calculated the t_obs,beta_i, but i do not understand what i am supposed to do in this next step. specifically, i have no idea what P is, and i suspect (T>|t_obs,beta_i|) should be a binary value? like 1 or 0?

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    Re: Finding the p value

    Can you add any more content, such as the statistical test you are performing or a screenshot of the actual problem?
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    Re: Finding the p value

    This is the method i should use

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    Re: Finding the p value

    This is the task i am asked

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    Re: Finding the p value

    Well it seems like you may be doing a two-sided t-test based on a regression coefficient. The 2P, is the multiplication of the p-value you had looked up on the t-distribution, times 2, since it is a two-sided hypothesis, meaning it could be different by being significantly more or less, no directionality in the difference just that it is different from the null.
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    Re: Finding the p value

    Thanks for clarifying, it helps yet i do not understand how i do the computation at step 3.

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    Re: Finding the p value

    What i dont understand:

    What is T ?
    how do i do the computation of (T> |t_obs,bi|)?

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    Re: Finding the p value

    Did you calculate a test statistic in step 2? If so, what is it?
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    Re: Finding the p value

    The calculation i did for step 2:


    β_2=-0.0024044
    β_0=4.073
    σ_g=0.004414



    t_(obs,β_i )=(β_2-β_0)/σ_g =-9557.107

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    Re: Finding the p value

    Well that value can get converted into a p-value if you know your degrees of freedom. I believe it is usually n-1.
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    Re: Finding the p value

    I know my degree of freedom to be 573.

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    Re: Finding the p value

    Well you are lucking out, I am waiting to see if someone replies to my post, so I am in the cyber-neighborhood.


    Look at this wonderful page I found just for you bok11:


    http://www.cyclismo.org/tutorial/R/pValues.html


    I didn't punch all of your numbers in but I quickly got the following based on your t-statistic:


    5.565753e-11

    Are you following all of your above steps and understanding what all of the values mean?
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    Re: Finding the p value


    Sorry I got sloppy above and didn't insert all of the numbers. I believe it should be this:


    2*pt(-abs(-9557.107),df=573)


    Which you may need to force to show you more digits if desired or otherwise it is, p<0.0001.


    With experience you will recognize that 9557 is a big number.
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