ozone2                package:fields                R Documentation

_D_a_i_l_y _8-_h_o_u_r _o_z_o_n_e _a_v_e_r_a_g_e_s _f_o_r _s_i_t_e_s _i_n _t_h_e _M_i_d_w_e_s_t

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

     The response is 8-hour average (surface) ozone ( from 9AM-4PM)
     measured in parts per billion (PPB) for 153 sites in the
     midwestern US over the period June 3,1987 through August 31, 1987,
     89 days. This season of high  ozone corresponds with a large
     modeling experiment using the EPA Regional Oxidant Model.

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

     data(ozone2)

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

     The data list has components: <s-args> <s-arg name="y"> a 89X153
     matrix of ozone values. Rows are days and columns are the  sites. 
     </s-arg> </s-arg name="lon.lat">  Site locations in longitude and
     latitude as a 153X2 table </s-arg> <s-arg name="chicago.subset">
     Logical vector indicating stations that form teh smaller 
     Chicagoland subset. (see FIELDS ozone data set) </s-arg> </s-args>
     <s-section name="Reference"> Nychka, D., Cox, L., Piegorsch, W.
     (1998) Case Studies in Environmental  Statistics Lecture Notes in
     Statistics, Springer Verlag, New York

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

     data( ozone2)

     # pairwise correlation among all stations
     # ( See cover.design to continue this example)
     cor.mat<- cor( ozone2$y, use="pairwise")

     #raw data image for day number 16 
     good<- !is.na( ozone2$y[16,])
     out<- as.image( ozone2$y[16,good], x=ozone2$lon.lat[good,])
     image.plot( out)

