Errors of Measurement

To ensure the quality of a product, errors of measurement is very important, as test cases are executed at various levels defects if found any in the tested area. The defects are logged and data is collected. The defects are then fixed. The testing team verifies if the defect was really fixed and closes the defects. This information is very beneficial. Proper tracking ensures that all defects were fixed. This information also helps in future projects.

Variation in a process has two sources:

• Variation of the process that makes the product.
• Variation of the measurement process.

Even when rightly used, a measuring instrument may not give a true reading of a characteristic. The distinction between the true value and the measured value can be due to one or more five sources of variation.

Bias is the difference between the observed average of measurements and the reference value. The reference value is also termed as accepted reference value or master value. It is a value that serves as an agreed-upon reference for the measured values.

Any statement of bias and repeatability must be preceded by three conditions:

• Definition of the test method: this definition includes the step-by-step procedure, equipment to be used, preparation of test specimens, test conditions and so on.

• Definition of the system of causes of variability: these include materials, analysts, apparatus, and laboratories.
• Existence of a statistically controlled measurement process: the measurement process must have stability for the statements on bias and precision to be valid.

Errors of measurement can cause incorrect decisions on:

• Individual units of product.
• Lots submitted to sample the plans.

In the classification of a product, two types of errors can occur, they are:

• A non conforming unit can be accepted (the consumer's risk).
• A conforming unit can be rejected (the producer's risk).

Posted Date: 9/29/2012 2:44:08 AM | Location : United States

Ask an Expert

Related Discussions:- Errors of measurement in quality of product, Assignment Help, Ask Question on Errors of measurement in quality of product, Get Answer, Expert's Help, Errors of measurement in quality of product Discussions

Write discussion on Errors of measurement in quality of product
Your posts are moderated

Write your message here..

Related Questions

Materials requirement planning, what are the draw backs in the adoption of ... what are the draw backs in the adoption of the materials requirement planning system

Purchasing and supply.., 5 steps in the process of evaluating the purchasin... 5 steps in the process of evaluating the purchasing and supply system

describe channel strategy, 1. Describe in general the type of channels you... 1. Describe in general the type of channels you might utilize for your product/service? Why do you think it is appropriate? 2. How do you think this channel strategy will

Explain the unique characteristics of dairy supply chain, Explain the uniqu... Explain the unique characteristics of dairy supply chain. Dairy Supply chain - Farmers, Cooperatives, Processors, Retail Outlets, Consumers; Characteristics of dairy supply cha

Pricing , Hello, I have one question please. How much per page? Hello, I have one question please. How much per page?

Mrp systems., mrp mrp

Mc donalds operations, i am a management trainee and currently i am working... i am a management trainee and currently i am working with a supply chain company which deals with supply of raw materials all over India to Mc Donalds. I am tryin to implement a be

E-commerce, 1. Based on your own research on the use of e-commerce/e-procur... 1. Based on your own research on the use of e-commerce/e-procurement in the public and private sectors, what are those elements that you consider to be unique to each? 2. How woul

VENDOR DEVELOPMENT, WHAR ARE THE RESPONSIBILITIES? WHAR ARE THE RESPONSIBILITIES?

Materials management operations, discuss discuss