Mean deviation, Applied Statistics

First Moment of Dispersion or Mean Deviation

Mean deviation or the average deviation is the measure if dispersion which   is based upon all the items in a variable .It is the arithmetic mean of the deviations of the values from a measure of central tendency   In the words of Clark and schkade average deviation is the average amount of scatter of items distribution from either mean or the median ignoring sings of the deviations.

Thus it is a measure obtained by calculating the absolute deviations of each observation from the media or the mean, taking all deviations as positive, and then averaging these decimations by taking their arithmetic mean. Mean deviation from arithmetic mean is also called first moment of dispersion.

The following process is adopted for its calculation:

(1)   Choice of Average : Theoretically mean deviation may be computed from any average mean or median or mode but in practice median and mean   are popular, of the two the use of median is better since sum of the deviations of observations is the least from median, as such unless specifically    nothing is given in the question median should be used.

(2)   Ignoring sings:  In its computation the algebraic sings of the deviations are ignored i.e. all the deviations are taken as positive. To indicate deviations are absolute and sings are ignored.

(3)   Mean of the Deviations:  The total of sum of the deviations is divided by the number of items, the quotient or the result is the mean deviation.

(4)   Formula: Mean deviation is expressed by the greek letter small delta as such.

(5)   Mean deviation from Mean

(6)   Mean deviation from Median

(7)   Mean deviation from Mode

Coefficient of Mean Deviation: The purpose of comparing variations or dispersal between two or more different sets of data a relative measure is computed using the following formula .

Coefficient of mean deviation from mean =x/x

Coefficient of mean deviation from median=m/m

Coefficient of mean deviation from mode= z/z

Posted Date: 9/26/2012 7:37:44 AM | Location : United States

Related Discussions:- Mean deviation, Assignment Help, Ask Question on Mean deviation, Get Answer, Expert's Help, Mean deviation Discussions

Write discussion on Mean deviation
Your posts are moderated
Related Questions
Choose any published database from the internet or Bethel library (such as those from the Census Bureau or any financial sites). You may opt to use one of the data files provided b

The box plot displays the diversity of data for the totexp; the data ranges from 30 being the minimum value and 390 being the maximum value. The box plot is positively skewed at 1.

In recent years a number of calculators are available for doing statistical calculations over and above the usual addition, subtraction, multiplication and division. The fx-82 mode

Find unlabeled data set test.txt and initial centroids data set centroids.txt in the archive, both files have the following format: [attribute1_value attribute2_value ...

Ask 3. Precision Manufacturing has a government contract to produce stainless steel rods for use in military aircraft. Each rod is required to be 20 millimeters in diameter. Each

The file Midterm Data.xls has a tab labeled "Many vs. S&P" which presents historical price data for several assets, a volatility condition (VIDX = 1 if the NYSE volatility is grea

Geometric Mean The geometric mean   of numbers is defined as the th root of the product of numbers .It is obtained by multiplying all the values of a variable and then extracti

Correspondence analysis is an exploratory technique used to analyze simple two-way and multi-way tables containing measures of correspondence between the rows and colulnns of an

This question has two parts with multiple items to answer. You are a psychologist who has collected the subjective well-being scores of a number of elderly people aged 90 or abo

1. Recognize and explain the opportunities for statistical learning. 2. Describe how the use of statistics supports student learning. 3. Recognize appropriate data displays a