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We introduce random survival forests, a random forests method for the analysis of right-censored survival data. New survival splitting rules for growing survival trees are introduced, as is a new missing data algorithm for im-puting missing data. A conservation-of-events principle for survival forests is introduced and used to define ensemble mortality, a(More)
BACKGROUND The increase in heart rate that accompanies exercise is due in part to a reduction in vagal tone. Recovery of the heart rate immediately after exercise is a function of vagal reactivation. Because a generalized decrease in vagal activity is known to be a risk factor for death, we hypothesized that a delayed fall in the heart rate after exercise(More)
This document details the procedures and recommendations of the Goals and Metrics Committee of the Strategic Planning Task Force of the American Heart Association, which developed the 2020 Impact Goals for the organization. The committee was charged with defining a new concept, cardiovascular health, and determining the metrics needed to monitor it over(More)
The minimal depth of a maximal subtree is a dimensionless order statistic measuring the predictiveness of a variable in a survival tree. We derive the distribution of the minimal depth and use it for high-dimensional variable selection using random survival forests. In big p and small n problems (where p is the dimension and n is the sample size), the(More)
BACKGROUND Abnormal heart rate recovery after symptom-limited exercise predicts death. It is unknown whether this is also true among patients undergoing submaximal testing. OBJECTIVE To test the prognostic implications of heart rate recovery in cardiovascularly healthy adults undergoing submaximal exercise testing. DESIGN Population-based cohort study.(More)
BACKGROUND Previous reports have suggested that an attenuated exercise heart rate response may be associated with coronary heart disease risk and with mortality. These observations may parallel the association between reduced heart rate variability during normal activities and adverse outcome. This investigation was designed to look at the prognostic(More)