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SAS/Ets 9.22 User's Guide 100. Provides detailed reference material for using SAS/ETS software and guides you through the analysis and forecasting of features such as univariate and multivariate time series, cross-sectional time series, seasonal adjustments, multiequational nonlinear models, discrete choice models, limited dependent variable models, portfolio analysis, and generation of financial reports, with introductory and advanced examples for each procedure. You can also find complete information about two easy-to-use point-and-click applications: the Time Series Forecasting System, for automatic and interactive time series modeling and forecasting, and the Investment Analysis System, for time-value of money analysis of a variety of investments | 982 F Chapter 17 The MDC Procedure Output 17.5.4 shows the summary table that is produced by the preceding statements. Output 17.5.4 Average Probabilities of Choosing Each Particular Alternative The MEANS Procedure Analysis Variable probs alt Mean 1 0.0178197 2 0.0161712 3 0.0972584 4 0.0294659 5 0.0594076 6 0.1653871 7 0.1118181 8 0.1043445 9 0.3564940 10 0.0272324 11 0.0096334 12 0.0049677 Now you change the preference parameter for variable D2L. In order to fix all the parameters you use the MAXIT 0 option to prevent optimization and the START option in MODEL statement to specify initial parameters. Two-level Nested Logit proc mdc data small maxit 0 outest a model decision r15 r10 ttime ttime_cp sde sde_cp sdl sdlx d2l type nlogit choice alt start 1.1034 0.3931 -0.0465 -0.0498 -0.6618 0.0519 -2.1006 -3.5240 -2.0941 0.6762 1.0906 0.7622 id id utility u 1 r15 r10 ttime ttime_cp sde sde_cp sdl sdlx d2l nest level 1 1 2 3 4 5 6 7 8 @ 1 9 @ 2 10 11 12 @ 3 level 2 1 2 3 @ 1 output out predicted2 p probs run Example 17.5 Choice of Time for Work Trips Nested Logit Analysis F 983 You apply the same SORT and MEANS procedures as applied earlier to obtain the following summary table in Output 17.5.5. Output 17.5.5 Average Probabilities of Choosing Each Particular Aalternative after Changing the Preference Parameter The MEANS Procedure Analysis Variable probs alt Mean 1 0.0207766 2 0.0188966 3 0.1138816 4 0.0345654 5 0.0697830 6 0.1944572 7 0.1315588 8 0.1228049 9 0.2560674 10 0.0236178 11 0.0090781 12 0.0045128 Comparing the two tables shown in Output 17.5.4 and Output 17.5.5 you clearly see the effect of increased dislike of late arrival. People shifted their choices towards earlier times alternatives 1-8 from the on-time option alternative 9 . Brownstone and Small 1989 also estimate the two-level nested logit model with equal scale parameter constraints T1 t2 r3. Replication of their model estimation is shown in the following statements Nested Logit with Equal .
