1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Simple/silly question

  1. Jul 6, 2004 #1
    In studies, they always refer to certain variable values or something. Like: one-sample t (64) = 7.02, p < .0001. This overestimation occurred even though self-ratings of ability were significantly correlated with our measure of actual ability, r (63) = .39, p < .001 or This was true for the first set of self-appraisals, &Beta s(67) = - .40 to - .49, p s < .001, as well as the second, &Beta s(67) = - .41 to - .50, p s < .001

    what are t, p, r etc. ? :confused:

    I know I should know this but it's been a looooooong time.


    Poop. Those "&Beta"s are meant to be Beta symbols.
     
    Last edited: Jul 6, 2004
  2. jcsd
  3. Jul 6, 2004 #2

    chroot

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Can you provide a link to the entire source material? It is possible that this is some kind of notation common in the field from which this quote came from.

    - Warren
     
  4. Jul 6, 2004 #3
    This sounds like an abstract from a psychological studies. I am not sure about the symbols. But in general in statistics, "r" refers to the "sample correlation coefficient" between two variables. "r" lies in the range from -1 to 1. A positive (negative) value indicates a positive (negative) *linear* correlation between the two variables. Since in studies we can only take a finite number of samples, we can only hope to estimate r using the data that are available to us. In this process of estimation there is likely to be "errors".

    As to "p", it is called the "p value" and 1-p is called the "confidence level". It is tied with something called "hypothesis testing" in statistics. I do not see any hypothesis in the piece of writing so I cannot explain it.

    As to the one sample t and beta, I think they are some "test statistics" for some hypothesises. But without knowing the hypothesises I cannot say any further.
     
  5. Jul 7, 2004 #4

    uart

    User Avatar
    Science Advisor

    "t(n)" most likely refers to t-distribution of n degrees of freedom and "p" is the probability that the given "t" results could have occured purely by chance given the "null hypothoses". Note the a "t" distribution is a common probability density function that is quite similar to the Normal distribution. The quoted example is a little unusual as "t" distributions with degrees of freedom greater than 30 are rarely used as they are extremely well approximated with the normal distribution.

    "r" is a corelation coefficient, and "Beta" is yet another distribution function.
     
    Last edited: Jul 7, 2004
  6. Jul 8, 2004 #5
    Thanks guys. That was indeed from a psychological study (http://www.apa.org/journals/psp/psp7761121.html - a most interesting read!), but I've seen similar notation in numerous other places. thanks again.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Simple/silly question
  1. Silly kinda question. (Replies: 3)

  2. 2 silly questions (Replies: 10)

  3. Silly question (Replies: 7)

Loading...