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  2. Proportional hazards model - Wikipedia

    en.wikipedia.org/wiki/Proportional_hazards_model

    This interpretation of the baseline hazard as "hazard of a baseline subject" is imperfect, as the covariate being 0 is impossible in this application: a P/E of 0 is meaningless (it means the company's stock price is 0, i.e., they are "dead"). A more appropriate interpretation would be "the hazard when all variables are nil".

  3. Hazard ratio - Wikipedia

    en.wikipedia.org/wiki/Hazard_ratio

    In survival analysis, the hazard ratio (HR) is the ratio of the hazard rates corresponding to the conditions characterised by two distinct levels of a treatment variable of interest. For example, in a clinical study of a drug, the treated population may die at twice the rate of the control population.

  4. Discrete-time proportional hazards - Wikipedia

    en.wikipedia.org/wiki/Discrete-time_proportional...

    This approach performs well for certain measures and can approximate arbitrary hazard functions relatively well, while not imposing stringent computational requirements. [5] When the covariates are omitted from the analysis, the maximum likelihood boils down to the Kaplan-Meier estimator of the survivor function. [6]

  5. Failure rate - Wikipedia

    en.wikipedia.org/wiki/Failure_rate

    A concept closely-related but different [2] to instantaneous failure rate () is the hazard rate (or hazard function), (). In the many-system case, this is defined as the proportional failure rate of the systems still functioning at time t {\displaystyle t} (as opposed to f ( t ) {\displaystyle f(t)} , which is the expressed as a proportion of ...

  6. Accelerated failure time model - Wikipedia

    en.wikipedia.org/wiki/Accelerated_failure_time_model

    In full generality, the accelerated failure time model can be specified as [2] (|) = ()where denotes the joint effect of covariates, typically = ⁡ ([+ +]). (Specifying the regression coefficients with a negative sign implies that high values of the covariates increase the survival time, but this is merely a sign convention; without a negative sign, they increase the hazard.)

  7. Hazard analysis - Wikipedia

    en.wikipedia.org/wiki/Hazard_analysis

    ANSI/GEIA-STD-0010-2009 (Standard Best Practices for System Safety Program Development and Execution) is a demilitarized commercial best practice that uses proven holistic, comprehensive and tailored approaches for hazard prevention, elimination and control. It is centered around the hazard analysis and functional based safety process.

  8. Nelson–Aalen estimator - Wikipedia

    en.wikipedia.org/wiki/Nelson–Aalen_estimator

    The Nelson–Aalen estimator is a non-parametric estimator of the cumulative hazard rate function in case of censored data or incomplete data. [1] It is used in survival theory, reliability engineering and life insurance to estimate the cumulative number of expected events. An "event" can be the failure of a non-repairable component, the death ...

  9. Hierarchy of hazard controls - Wikipedia

    en.wikipedia.org/wiki/Hierarchy_of_hazard_controls

    For example, construction professionals cannot remove the danger of asbestos when handling the hazardous agent is the core of the task. [3] The most effective control measure is eliminating the hazard and its associated risks entirely. The simplest way to do this is by not introducing the hazard in the first place.