stretchbetaval            package:popbio            R Documentation

_G_e_n_e_r_a_t_e _s_t_r_e_t_c_h_e_d _b_e_t_a-_d_i_s_t_r_i_b_u_t_e_d _r_a_n_d_o_m _n_u_m_b_e_r_s

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

     Generate a stretched beta number with mean, standard deviation,
     minimum and maximum values and CDF value for bounded fertility
     estimates

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

     stretchbetaval(mn, std, minb, maxb, fx)

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

      mn: mean of a fertility rate 

     std: standard deviation

    minb: minimum value  

    maxb: maximum value  

      fx: Cumulative Distribution Function value 

_D_e_t_a_i_l_s:

     This function calls function 'betaval'.

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

     Returns a stretched beta number with mean mn, standard deviation
     std, minimum and maximum values (minb, maxb) and CDF value fx.

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

     Original MATLAB script by Morris & Doak (2002: 283). Adapted to R
     by Patrick Nantel, 11 July 2005.

_S_o_u_r_c_e:

     converted Matlab code from Box 8.5 in Morris and Doak (2002)

_R_e_f_e_r_e_n_c_e_s:

     Morris, W. F., and D. F. Doak. 2002. Quantitative conservation
     biology: Theory and practice of population viability analysis.
     Sinauer, Sunderland, Massachusetts, USA.

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

     'betaval'

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

     stretchbetaval(3, 1.2, 1, 20, runif(1))

      # Generates stretchbeta random
      # fertilities for a population of 1000 mature individuals (Ni) with mean
      # fertility (f) of 3.0 and inter-individual variance in fertility (varF) of 1.5.
      
      Ni   <- 1000
      f    <-    2.5
      varF <-    1
      fmin <- 1
      fmax <- 5
      rndfert<-numeric(Ni) 
     for(i in 1:Ni)
     {
        rndfert[i]  <- stretchbetaval(f, sqrt(varF), fmin, fmax, runif(1)) 
     }
      hist(rndfert,20, main="Stretched beta-distributed random fertilities", 
     xlab="Fertility rate", , col="blue") 

