stone                package:DCluster                R Documentation

_S_t_o_n_e'_s _T_e_s_t

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

     Stone's Test is used to assess risk around given locations (i. e.,
     a putative pollution source). The null hypotheses is that relative
     risks are constant across areas, while the alternative is that
     there is descending trend in relative risks as distance to the
     focus increases. That is

       H_0  :  theta_1 = ... = theta_n = lambda
       H_1  :  theta_1 >= ... >= theta_n

     Supposing data sorted by distance to the putative pollution
     source, Stone's statistic is as follows:


             max_j [(sum_i=1 ^j O_i) / (sum_i=1 ^j E_i)]


     Depending on whether lambda is known (usually 1) or not, E_i may
     need a minor correction, which are not done automatically. See
     _achisq_ manual page for details.

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

     Stone, R. A. (1988). Investigating of excess environmental risks
     around putative sources: Statistical problems and a proposed test.
     Statistics in Medicine 7,649-660.

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

     DCluster, stone.stat, stone.boot, stone.pboot

