Chi V X, Chau N P
INSSET de St Quentin, Université de Picardie, France.
Biometrics. 1996 Mar;52(1):286-90.
Explicit formulas for the distribution function, the expectation, and the variance of the ratio X/Y were calculated, where X and Y are dependent variables. We assumed that the pair (X, Log Y) has a bivariate normal distribution. The work was motivated by a recent draft from the American Food and Drug Administration (FDA) on the treatment of high blood pressure (FDA, 1990, Draft of the Proposed Guidelines for the Clinical Evaluation of Antihypertensive Drugs). The effect of antihypertensive drugs on blood pressure usually achieves a peak level and then decreases to a trough level before the next dose. The FDA recommended that the ratio of trough-to-peak effects should be at least 0.5. It is well known that trough and peak effects are correlated.
计算了比率X/Y的分布函数、期望和方差的显式公式，其中X和Y是相关变量。我们假设(X, Log Y)对具有二元正态分布。这项工作的动机来自美国食品药品监督管理局（FDA）最近关于高血压治疗的一份草案（FDA，1990年，抗高血压药物临床评价拟议指南草案）。抗高血压药物对血压的作用通常会达到峰值水平，然后在下一次给药前降至谷值水平。FDA建议谷值与峰值效应的比率应至少为0.5。众所周知，谷值和峰值效应是相关的。
