Forecasting for any small business involves guesswork. You know your business and its past performance, but you may not be comfortable predicting the future. Using Excel is a great way to perform what ...

Abstract: Monitoring the ratio of two normal random variables (RZ) is one of the most important directions in Statistical Process Control (SPC). To enhance the sensitivity of traditional RZ charts in ...

It is shown that under fairly mild conditions linear combinations of independent normally distributed random variables with random coefficients tend to zero almost everywhere. The result is applied to ...