Common or random causes - causes of variability, Operation Management

Common or Random Causes - Causes of Variability

Consider throwing a pair of dice. The possible outcomes range from 2 to 12, but with different probabilities of occurrence (see figure below). Over a long series of throws, '2' would result in about 3 per cent (1/36) of the throws, and '7' would result in about 17 per cent (6/36) of them. However, the result of a particular throw is unpredictable. It will be determined by a number of variables which interact in a manner of which we have no detailed knowledge at the time of the throw e.g. the trajectories of the dice as they leave the hand, the microscopic contours of the surfaces of the dice and landing surface, the mechanical properties of the surfaces at the points of contact, etc. Such variables are called common causes.

2073_Common or random causes - causes of variability.png

When, in the long run, the outputs of a process can be expressed in probabilistic terms, the process is described as a common cause system. Manufacturing processes are typically common cause systems. That is, even when great care is taken in the set up and control of the process, variability of the output occurs. This variability cannot be reduced unless the process is changed. Statistical methods provide a means of registering common-cause variations and distinguishing them from the second type, assignable causes.

Posted Date: 3/15/2013 5:13:18 AM | Location : United States







Related Discussions:- Common or random causes - causes of variability, Assignment Help, Ask Question on Common or random causes - causes of variability, Get Answer, Expert's Help, Common or random causes - causes of variability Discussions

Write discussion on Common or random causes - causes of variability
Your posts are moderated
Related Questions
Production Control Meaning and Definition Production control involves implementation of production plans or schedules by coordinating different activities. It seeks to

HOW TO CARE FOR A TODDLERn #Minimum 100 words accepted#

Tools and Techniques of Layout Planning Various techniques are available for planning the layout. The most commonly used techniques is the use of two dimensional templates. O

Develop a way that Pandora could benefit from grid computing

How would the EBQ change if the set-up costs were reduced by 50 percent, and the holding costs were reassessed by 40 percent, taking account of the opportunity costs of capital at

Discuss how laws tie into business ethics. Support your ideas with research and specific examples of laws discussed in your text.

A local bar serves a premium draft beer to its customers. The daily demand for beer is assumed to follow a normal distribution with a mean of 80 litres and a standard deviation of

Productivity is a relative measure is true or false

An electrical contractor's records during the last 5 weeks indicate the number of actual job requests. Predict the number of requests for week 6 using each of the below methods:

Develop a Work Breakdown Structure (WBS) for a project in which you are going to build a bicycle and identify two major components with three levels of details for each component