jenks71               package:classInt               R Documentation

_I_l_l_i_n_o_i_s _1_9_5_9 _c_o_u_n_t_y _g_r_o_s_s _f_a_r_m _p_r_o_d_u_c_t _v_a_l_u_e _p_e_r _a_c_r_e

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

     Classic data set for the choice of class intervals for choropleth
     maps.

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

     data(jenks71)

_F_o_r_m_a_t:

     A data frame with 102 observations on the following 2 variables.

     '_j_e_n_k_s_7_1' a numeric vector: Per acre value of gross farm products
          in dollars by county for Illinois in 1959

     '_a_r_e_a' a numeric vector: county area in square miles

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

     Jenks, G. F., Caspall, F. C., 1971. "Error on choroplethic maps:
     definition, measurement, reduction". Annals, Association of
     American Geographers, 61 (2), 217-244

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

     data(jenks71)
     (jenks71)

