Lnorm-class              package:distr              R Documentation

_C_l_a_s_s "_L_n_o_r_m"

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

     The log normal distribution has density

   d(x) = 1/(sqrt(2 pi) sigma x) e^-((log x - mu)^2 / (2 sigma^2))

     where mu, by default =0, and sigma, by default =1, are the mean
     and standard deviation of the logarithm. C.f. 'rlnorm'

_O_b_j_e_c_t_s _f_r_o_m _t_h_e _C_l_a_s_s:

     Objects can be created by calls of the form 'Lnorm(meanlog,
     sdlog)'. This object is a log normal distribution.

_S_l_o_t_s:

     '_i_m_g': Object of class '"Reals"': The space of the image of this
          distribution has got dimension 1 and the name "Real Space". 

     '_p_a_r_a_m': Object of class '"LnormParameter"': the parameter of this
          distribution (meanlog and sdlog), declared at its
          instantiation 

     '_r': Object of class '"function"': generates random numbers (calls
          function 'rlnorm')

     '_d': Object of class '"function"': density function (calls
          function 'dlnorm')

     '_p': Object of class '"function"': cumulative function (calls
          function 'plnorm')

     '_q': Object of class '"function"': inverse of the cumulative
          function (calls function 'qlnorm')

_E_x_t_e_n_d_s:

     Class '"AbscontDistribution"', directly.
      Class '"UnivariateDistribution"', by class
     '"AbscontDistribution"'.
      Class '"Distribution"', by class '"AbscontDistribution"'.

_M_e_t_h_o_d_s:

     _i_n_i_t_i_a_l_i_z_e 'signature(.Object = "Lnorm")': initialize method 

     _m_e_a_n_l_o_g 'signature(object = "Lnorm")': returns the slot 'meanlog'
          of the parameter of the distribution 

     _m_e_a_n_l_o_g<- 'signature(object = "Lnorm")': modifies the slot
          'meanlog' of the parameter of the distribution 

     _s_d_l_o_g 'signature(object = "Lnorm")': returns the slot 'sdlog' of
          the parameter of the distribution 

     _s_d_l_o_g<- 'signature(object = "Lnorm")': modifies the slot 'sdlog'
          of the parameter of the distribution 

_N_o_t_e:

     The mean is E(X) = exp(mu + 1/2 sigma^2), and the variance Var(X)
     = exp(2*mu + sigma^2)*(exp(sigma^2) - 1) and hence the coefficient
     of variation is sqrt(exp(sigma^2) - 1) which is approximately
     sigma when that is small (e.g., sigma < 1/2).

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

     Thomas Stabla Thomas.Stabla@uni-bayreuth.de,
      Florian Camphausen Florian.Camphausen@uni-bayreuth.de,
      Peter Ruckdeschel Peter.Ruckdeschel@uni-bayreuth.de,
      Matthias Kohl Matthias.Kohl@uni-bayreuth.de

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

     'LnormParameter-class' 'AbscontDistribution-class' 'Reals-class'
     'rlnorm'

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

     L=Lnorm(meanlog=1,sdlog=1) # L is a lnorm distribution with mean=1 and sd=1.
     r(L)(1) # one random number generated from this distribution, e.g. 3.608011
     d(L)(1) # Density of this distribution is 0.2419707 for x=1.
     p(L)(1) # Probability that x<1 is 0.1586553.
     q(L)(.1) # Probability that x<0.754612 is 0.1.
     meanlog(L) # meanlog of this distribution is 1.
     meanlog(L)=2 # meanlog of this distribution is now 2.

