kappa2N                package:GeneTS                R Documentation

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_D_e_s_c_r_i_p_t_i_o_n:

     The degree of freedom kappa of the sample distribution of the
     correlation coefficient depends both on the sample size N and the
     number G of investigated variables,  i.e. whether simple or
     partial correlation coefficients are being considered. For G=2
     (simple correlation coefficient) the degree of freedom equals
     kappa = N-1, whereas for arbitrary G (with G-2 variables
     eliminated in the partial correlation coefficient) kappa = N-G+1
     (see also 'dcor0').

     The function 'kappa2N' returns the sample size that corresponds to
     a given degree of freedom kappa, whereas 'N2kappa' converts sample
     size to the corresponding degree of freedom.

_U_s_a_g_e:

     kappa2N(kappa, G=2)
     N2kappa(N, G=2)

_A_r_g_u_m_e_n_t_s:

   kappa: degree of freedom

       G: number of variables (G=2 corresponds to simple correlation)

       N: sample size

_V_a_l_u_e:

     The sample size N corresponding to a given kappa, or the degree of
     freedom kappa corresponding to a given N.

_A_u_t_h_o_r(_s):

     Juliane Schaefer (<URL:
     http://www.stat.uni-muenchen.de/~schaefer/>) and Korbinian
     Strimmer (<URL: http://www.stat.uni-muenchen.de/~strimmer/>).

_S_e_e _A_l_s_o:

     'dcor0', 'cor0.estimate.kappa'.

_E_x_a_m_p_l_e_s:

     # load GeneTS library
     library(GeneTS)

     # sample sizes corresponding to kappa=7
     kappa2N(7)     # simple correlation
     kappa2N(7, 40) # partial correlation with 40 variables

     # degree of freedom corresponding to N=100
     N2kappa(100)
     N2kappa(100,40)

