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Schechter Function

  1. Jan 3, 2012 #1
    Schechter Function....

    I''m very confused with what the difference is between the Schechter Function and 'Maximum likelihood method' or 1/Vmax method? Are the later two methods to be applied to the Schechter or are they completely different functions to calculate LF altogether?

  2. jcsd
  3. Jan 8, 2012 #2
    Re: Schechter Function....

    These are completely different things. The Schechter function describes the luminosity function of galaxies [see: http://en.wikipedia.org/wiki/Luminosity_function_(astronomy [Broken]) ]; while the maximum likelihood and 1/vmax methods are statistical methods of fitting a function (e.g. the Schechter function) to a set of data [see: http://en.wikipedia.org/wiki/Maximum_likelihood ]
    Last edited by a moderator: May 5, 2017
  4. Jan 9, 2012 #3
    Re: Schechter Function....

    OK. What do you think is the best method for fitting Schechter function for Galaxy Groups? The distance is roughly similar for these galaxies, so 1/Vmax method wouldnt be applicable right?

  5. Jan 10, 2012 #4
    Re: Schechter Function....

    I'm not sure, I've never done it myself. I'm sure it depends on the situation---and I'm sure you're right, if the distances are comparable, 1/Vmax isn't doing much.
    I think there is also a lot of variety on how to implement a maximum likelihood method---I don't think its a specific algorithm.
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