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Quality and Reliability Methods - SAS

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386 <strong>Reliability</strong> <strong>and</strong> Survival Analysis II Chapter 20<br />

Proportional Hazards Model<br />

Figure 20.15 ICDevice Output<br />

Example: Right-Censored Data; Tobit Model<br />

The Tobit model is normal, truncated at zero. However, you can take the exponential of the response <strong>and</strong> set<br />

up the intervals for a right-censored problem. In Tobit2.jmp, found in the <strong>Reliability</strong> folder of the sample<br />

data, run the attached script to estimate the lognormal.<br />

Proportional Hazards Model<br />

The proportional hazards model is a special semiparametric regression model proposed by D. R. Cox (1972)<br />

to examine the effect of explanatory variables on survival times. The survival time of each member of a<br />

population is assumed to follow its own hazard function.

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