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
Discuss strengths and threats to the survival of the military health system. Summarize the Tricare program and detail its options for enrolees. What is Tricare's greatest threat an

Suppose you run HR at a large organization. How will you determine supply and demand? How will employee turnover factor into your decisions? Suppose you want to retain your two

Can a factory be fast, dependable, flexible, produce high-quality products, and still provide poor service from a customer's perspective?

1. The purpose of supply chain management is to synchronize a firms processes with those of its suppliers and customers. 2. Supply chain management tries to match the flow of ma

Quesrion: Oceania Hospitals has recorded demand for heart transplant surgery over the past few years. The data is given in the following table: a) You have been hired

Problem 4: Comp-Max Computers assembles computers and computer equipment. It is about to start production of three new types of computers, called model A, B, and C, respectively. E

Line Balancing of Product Layouts A major consideration in the design of product layouts is that of bottlenecks; just as the strength of a chain is determined by its weakest

Describe the generic product development process described in this chapter. How does this process change for "technology push" products?

How do you determine as a project manager when project work should be contracted out, and how does risk enter into the decision?