Adaptive sample size and sampling intervals schemes have been widely used to improve the statistical efficiency of Hotelling T control chart in detecting small changes when the quality of a product or a process can be characterised by the multivariate distribution of quality characteristics. In this paper, we design a Hotelling T scheme varying sample sizes and sampling intervals (VSSI-T) for a...

I develop a simple Hotelling model which corresponds the distribution of consumer preferences to the intensity of competition. This is a new perspective on consumer distribution in the Hotelling model. I impose two properties, mean preserving spread (MPS) and monotone likelihood ratio property (MLRP), on distribution functions. These properties provide a way to measure the intensity of competit...

We show that crude oil production from existing wells in Texas does not respond to current or expected future oil prices, contradicting a basic prediction of Hotelling’s (1931) canonical model of exhaustible resource extraction. In contrast, the drilling of new wells exhibits a strong price response, as does the rental rate on drilling rigs. To explain these observations, we reformulate Hotelli...

Hotelling’s T 2 statistic is an important tool for inference about the center of a multivariate normal population. However, hypothesis tests and confidence intervals based on this statistic can be adversely a¤ected by outliers. Therefore, we construct an alternative inference technique based on a statistic which uses the highly robust MCD estimator [9] instead of the classical mean and covarian...

Endpoint detection is very important undertaking on the side of getting a good understanding and figuring out if a plasma etching process is done in the right way, especially if the etched area is very small (0.1%). It truly is a crucial part of supplying repeatable effects in every single wafer. When the film being etched has been completely cleared, the endpoint is reached. To ensure the desi...