SpaceShuttle               package:vcd               R Documentation

_S_p_a_c_e _S_h_u_t_t_l_e _O-_r_i_n_g _F_a_i_l_u_r_e_s

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

     Data from Dalal et al. (1989) about O-ring failures in the NASA
     space shuttle program.  The damage index comes from a discussion
     of the data by Tufte (1997).

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

     data(SpaceShuttle)

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

     A data frame with 24 observations and 6 variables.

     _F_l_i_g_h_t_N_u_m_b_e_r Number of space shuttle flight.

     _T_e_m_p_e_r_a_t_u_r_e temperature during start (in degrees F).

     _P_r_e_s_s_u_r_e pressure.

     _F_a_i_l did any O-ring failures occur? (no, yes).

     _n_F_a_i_l_u_r_e_s how many (of six) 0-rings failed?.

     _D_a_m_a_g_e damage index.

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

     Michael Friendly (2000), Visualizing Categorical Data: <URL:
     http://euclid.psych.yorku.ca/ftp/sas/vcd/catdata/orings.sas>

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

     S. Dalal, E. B. Fowlkes, B. Hoadly (1989), Risk analysis of the
     space shuttle: Pre-Challenger prediction of failure, _Journal of
     the American Statistical Association_, *84*, 945-957.

     E. R. Tufte (1997), _Visual Explanations: Images and Quantities,
     Evidence and Narrative_. Graphics Press, Cheshire, CT. 

     M. Friendly (2000), _Visualizing Categorical Data_. SAS Institute,
     Cary, NC.

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

     data(SpaceShuttle)
     plot(nFailures/6 ~ Temperature, data = SpaceShuttle,
          xlim = c(30, 81), ylim = c(0,1),
          main = "NASA Space Shuttle O-Ring Failures",
          ylab = "Estimated failure probability",
          pch = 19, col = 4)
     fm <- glm(cbind(nFailures, 6 - nFailures) ~ Temperature,
               data = SpaceShuttle,
               family = binomial)
     lines(30 : 81,
           predict(fm, data.frame(Temperature = 30 : 81), type = "re"),
           lwd = 2)
     abline(v = 31, lty = 3)

