aidsEla               package:micEcon               R Documentation

_E_l_a_s_t_i_c_i_t_i_e_s _o_f _t_h_e _A_I_D_S _m_o_d_e_l

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

     Calculates the demand elasticities of an AIDS model.

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

        aidsEla( coef, W, P = NULL, formula = "AIDS",
           qNames = NULL, pNames = NULL )

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

    coef: a list containing the coefficients alpha, beta and gamma.

       W: a vector of the shares at which the elasticities should be
          calculated.

       P: a vector of the prices at which the elasticities should be
          calculated.

 formula: the elsticity formulas to be used (see details).

  qNames: an optional vector of strings containing the names of the
          quantities to label elasticities.

  pNames: an optional vector of strings containing the names of the
          prices to label elasticities.

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

     At the moment only the elasticity formulas of the orginal AIDS
     ('AIDS'), the formula of Chalfant (1987) ('Ch') and the formula of
     Eales and Unnevehr (1988) ('EU') are implemented.

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

     a list containing following elements: 

 formula: the elasticity formula used to calculate these elasticities

     exp: vector of expenditure elasticities

marshall: matrix of Marshallian (uncompensated) price elasticities

   hicks: matrix of Hicksian (compensated) price elasticities

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

     Arne Henningsen ahenningsen@agric-econ.uni-kiel.de

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

     Chalfant, J.A. (1987) A Globally Flexible, Almost Ideal Demand
     System. _Journal of Business and Economic Statistics_, 5, p.
     233-242.

     Deaton, A.S. and J. Muellbauer (1980) An Almost Ideal Demand
     System. _American Economic Review_, 70, p. 312-326.

     Eales J.S. and L.J. Unnevehr (1988) Demand for beef and chicken
     products: separability and structural change. _American Journal of
     Agricultural Economics_, 70, p. 521-532.

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

     'aidsEst'

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

        data( Blanciforti86 )
        estResult <- aidsEst( c( "pFood1", "pFood2", "pFood3", "pFood4" ),
           c( "wFood1", "wFood2", "wFood3", "wFood4" ), "xFood",
           data = Blanciforti86, method = "LA:L" )
        wMeans <- colMeans( Blanciforti86[ , c( "wFood1", "wFood2",
           "wFood3", "wFood4" ) ] )
        aidsEla( estResult$coef, wMeans, formula = "Ch" )

