January 10th, 2008 . by Vanaja
One of the most important objectives of statistical analysis is to get one single value that describes the characteristic of the entire mass of unwieldy data. Such a value is called central value or an average or the expected value of the variable.

The term ” average ” has been defined by various authors. Some important definitions are given below.

- “Average is an attempt to find one single figure to describe whole of figures” -Clark

- ” An average is a single value selected from a group of values to represent them in some way-a value which is supposed to stand for whole group, of which it is a part, as typical of all the values in he group” -A.E Waugh

- ” An average is a typical value in the sense that it is sometimes employed to represent all the individual values in a series or of a variable” -Ya-Lun-Chou

- “An average is a single value within the range of the data that is used to represent all the values in the series.Since an average is somewhere within the range of the data. It is also called a measure of central value” - Croxton &Cowden

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September 9th, 2007 . by Vanaja
**A group consists of 50 students. Out of these 20 are girls .There are 10 Australian students. Out of 50 students, 25 students like cricket.**

What is the probability of selecting an Australian girl who likes cricket?

**Hint:**

Probability of selecting a girl= 20/50

Probability of selecting an Australian student = 10/50

Probability of a student like cricket=25/50

Therefore the the probability of selecting an Australian girl who likes cricket= (20/50 )(10/50)(25/50) = 1/25 =0.25

Posted in Problems and Solutions, Statistics ** | **
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August 9th, 2007 . by Vanaja
The word statistics conveys many meanings to people. to some it is another form of mathematics and for some other it suggests charts, graphs and tables which they find in newspapers and many other such things.

The study of statistics involves methods of refining numerical and non-numerical information into useful forms. In addition to meaning data, statitics also refers to a subject just as mathematics or physics. In this sense statistics is a body ofmethods of obtainining and analysing in order to make decisions on them.

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