inclusionprobabilities       package:sampling       R Documentation

_I_n_c_l_u_s_i_o_n _p_r_o_b_a_b_i_l_i_t_i_e_s

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

     Compute the first-order inclusion probabilities from a vector of
     positive numbers  (for probability proportional-to-size sampling).

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

     inclusionprobabilities(a,n)

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

       a: vector of positive numbers.

       n: sample size.

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

     'inclusionprobastrata'

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

     ############
     ## Example 1
     ############
     # a vector of positive numbers
     a<-1:20
     # computation of the inclusion probabilities for a sample size n=12
     pik=inclusionprobabilities(a,12)
     pik
     ############
     ## Example 2
     ############
     # Computation of the inclusion probabilities proportional to the number 
     # of inhabitants in each municipality of the Belgian database.
     data(belgianmunicipalities)
     pik=inclusionprobabilities(belgianmunicipalities$Tot04,200)
     # the first-order inclusion probabilities for each municipality
     data.frame(pik=pik,name=belgianmunicipalities$Commune)
     # the inclusion probability sum is equal to sample size
     sum(pik)

