改进的PWM方法及在材料抗压强度区间估计中的应用

Improved PWM Method and the Application on Interval Estimation of Material Compression Strength

材料抗压强度的试验数据往往是小样本数据,样本均值易受异常点的影响,导致采用经典方法得到的置信区间不具有稳健性。针对这一问题,改进了深度加权平均方法,结合不同材料抗压强度的数据进行研究,并比较了一般及加权处理的Bootstrap方法的区间估计数据。结果表明,采用改进后的深度加权平均方法得到的置信区间较短,并且具有更好的稳健性。

Material compression strength is extraordinarily important on engineering application. But the date of experiment is always small. The sample mean is vulnerable to the value of abnormal points based on its small sample data, which makes the confidence interval got by the classical method have non-robustness. This paper improves the method of PWM reasonably, and adopts the general Boot- strap sampling methods and the weighted one to compare the interval estimations. According to the da- ta of the material compression strength, the result is that the method of improved PWM has shorter confidence interval and much more robustness.