Chi-Square Distribution Question

Discussion in 'Chit Chat' started by Algo_Design_Kid, Nov 29, 2011.

  1. First question : Why is the peak of the distribution always just a bit before the actual dF?

    This can be seen here.. [​IMG]

    Second : Why when dF = 2 does the left side of the curve just go straight up the y axis and never find its way to 0?


    [​IMG]

    The teacher is totally puzzled in class and I can't find anything written in plain english that tells me why.


    Thanks
     
  2. FGBL07

    FGBL07

    You are misreading the graph for dF=2.

    Take a look at the density function: for dF=2 the function collapses to 0.5*e**(-x/2). The result for x=0 is 0.5.
     
  3. Seems you are right Chi Sq Pdf x= 0 is .5

    Can you actually explain what this means? Neither my teacher or book are helping.. I am probably missing something simple.