Computational predictions of the functional stenosis severity from coronary imaging data use an allometric scaling law to derive hyperemic blood flow (Q) from coronary arterial volume (V), Q = αV(β) Reliable estimates of α and β are essential for meaningful flow estimations. We hypothesize that the relation between Q and V depends on imaging resolution. In five canine hearts, fluorescent micros...

Let V be the m×m upper-left corner of an n× n Haar-invariant unitary matrix. Let λ1, · · · , λm be the eigenvalues of V. We prove that the empirical distribution of a normalization of λ1, · · · , λm goes to the circular law, that is, the uniform distribution on {z ∈ C; |z| ≤ 1} as m → ∞ with m/n → 0. We also prove that the empirical distribution of λ1, · · · , λm goes to the arc law, that is, t...

In survival or reliability studies, it is common to have truncated data due to the limited time span of the study or dropouts of the subjects for various reasons. The estimation of survivor function under left truncation was first discussed by Kaplan and Meier by extending the well known productlimit estimator of the survivor function. The focus of this paper is on the nonparametric estimation ...

SUMMARY Cause-specific hazard and cumulative incidence function are of practical importance in competing risks studies. Inferential procedures for these quantities are well developed and can be applied to semi-competing risks data, where a terminating event censors a non-terminating event, after coercing the data into the competing risks format. Complications arise when there is left truncation...

BACKGROUND We carried out a study to examine whether left truncation bias could explain the negative association between smoking and preeclampsia. METHODS Monte Carlo and other simulation models were used to determine the effect of differential rates of early pregnancy loss among smokers on the relation between smoking and preeclampsia at ≥20 weeks' gestation. Assumptions included no associat...

Many statistical methods for truncated data rely on the assumption that the failure and truncation time are independent, which can be unrealistic in applications. The study cohorts obtained from bone marrow transplant (BMT) registry data are commonly recognized as truncated samples, the time-to-failure is truncated by the transplant time. There are clinical evidences that a longer transplant wa...

Survival and reliability analyses deal with incomplete failure time data, such as censored truncated data. Recently, the classical left-truncation scheme was generalized to analyze “field data”, defined samples collected within a fixed period. However, existing competing risks models dealing left-truncated field data are not flexible enough. We propose copula-based for latent times, permitting ...