Central tendency of sample means, Operation Management

Central Tendency of Sample Means

As was shown earlier (Advantages of SPC: feedback, the use of individual output measurements as the basis for process adjustment is inappropriate. How, then, should the need for adjustment (and the amount of adjustment) be determined?

We can take advantage of the behaviour of the mean values of samples, as described in the central limit theorem:

If random samples of size n are taken from any population having a mean µ and a standard deviation σ, the probability distribution of the sample means approaches a normal distribution of mean µ and standard error s = σ/√n as n becomes very large. To appreciate the significance of this, consider the pharmaceutical process example. If a large number of samples, each of nine tablets (i.e. n = 9), are weighed and the means of the samples calculated, their distribution will approximate a normal distribution of mean 505.48 mg (µ) and standard error 1.82 mg (s= σ//√n = 5.45/3) This is illustrated in this figure.

733_Central Tendency of Sample Means.png

Because the sample means cluster more closely around the population mean than the individual measurements, they provide a sensitive measure of any tendency for the process mean to drift out of control.

Posted Date: 3/15/2013 5:45:15 AM | Location : United States







Related Discussions:- Central tendency of sample means, Assignment Help, Ask Question on Central tendency of sample means, Get Answer, Expert's Help, Central tendency of sample means Discussions

Write discussion on Central tendency of sample means
Your posts are moderated
Related Questions
Go toto gmi.org and search for "The Ten Commandments of America Culture." The list presents ten sayings that represent commonly accepted American cultural values. Think about how t

In this case study, you will review a case involving a functional system. The Lynx Company uses a functional system for their sales system. It takes the orders from their salesm

An analysis of order and shipment data shows that the order fill rate is 97.1% and ABBA collected the following data concerning customer service performance: Late delivery-5 per

Emotional intelligence; a key factor to success I want a 20 question survey for this topic, based on these 5 factors self-awareness, self-regulation, motivation, empathy, and socia

Diversification as a strategy. Consider GE and how large and global it is. What problems do you think GE's most senior executives encounter in trying to stay on top of all th

1.  Investigate: Consider the operations of your own organisation (or another with which you are familiar) and report on how its operational processes are designed. From your readi

Q. What is usefulness of flexible manufacturing systems to manufacturing operations? Flexible manufacturing systems (FMS) comprise a few machines with part and device handling

All work packages in a project: Answer Do not have to be at the same level of the WBS Must be at the same level of the WBS Do not have to be referenced in the Work Brea

PDAs, iPods, iPhones, iPads, most cell phones, and other data devices are miniature computer systems designed to be highly mobile. Describe how such devices could alter the typical

Business-level, Corporate-level, and International Strategies Using the Internet, research about the following: • Globalization • International strategic alliances • Co