Normal distribution, Mathematics

Assignment Help:

Normal Distribution

Figure 1

1015_normal distribution.png

The normal distribution reflects the various values taken by many real life variables like the heights and weights of people or the marks of students in a large class. In all these cases a large number of observations are found to be clustered around the mean value m and their frequency drops sharply as we move away from the mean in either direction. For example, if the mean height of an adult in a city is 6 feet then a large number of adults will have heights around 6 feet. Relatively a few adults will have heights of 5 feet or 7 feet.

Further, if we draw samples of size n (where n is a fixed number over 30) from any population, then the sample mean 89_computation of covariance ungrouped data2.png   will be (approximately) normally distributed with a mean equal to m i.e. the mean of the population.

The characteristics of normal probability distribution with reference to the above figure are

  1. The curve has a single peak; thus it is unimodal.

  2. The mean of a normally distributed population lies at the center of its normal curve.

  3. Because of the symmetry of the normal probability distribution, the median and the mode of the distribution are also at the center.

  4. The two tails of the normal probability distribution extend indefinitely and never touch the horizontal axis.

If s is the standard deviation of the normal distribution, 80% of the observation will be in the interval m -1.28s to m + 1.28s.

Figure 2

375_normal distribution1.png

95% of the observations will be in the interval m - 1.96s to m + 1.96s.

Figure 3

2353_normal distribution2.png

98% of the observations will lie in the interval m - 2.33 s to m + 2.33 s.

Figure 4

342_normal distribution3.png

 

 

Standard Normal Distribution

The Standard Normal Distribution is a normal distribution with a mean m = 0 and a standard deviation s = 1. The observation values in a standard normal distribution are denoted by the letter Z.


Related Discussions:- Normal distribution

Ellipse, How we find locus of the middle points of chord of an ellipse whic...

How we find locus of the middle points of chord of an ellipse which are drawn through the positive end of the minor axes

Differential equations, Find the normalized differential equation which has...

Find the normalized differential equation which has {x, xex} as its fundamental set

Find out the slope of equations, Example:  find out the slope of equations ...

Example:  find out the slope of equations and sketch the graph of the line.                         2 y - 6x = -2 Solution To get the slope we'll first put this in slope

Highest common factor (hcf), We know that a factor is a quantity whic...

We know that a factor is a quantity which divides the given quantity without leaving any remainder. Similar to LCM above we can find a highest common factor (HCF)

HELP, WHAT TWO SIX DIDGIT NUMBERS CAN YOU ADD 984,357

WHAT TWO SIX DIDGIT NUMBERS CAN YOU ADD 984,357

Ratios, a muffin recipe calls for three forth of a cup of sugar and one eig...

a muffin recipe calls for three forth of a cup of sugar and one eight of a cup of butter. travis accidentally put in one whole cup of butter. how much sugar does travis need to put

Graph of a function, Graph of a function Help me in understanding the ...

Graph of a function Help me in understanding the concept of graph of a function in linear algebra and matrices.

Wronskian, In the earlier section we introduced the Wronskian to assist us ...

In the earlier section we introduced the Wronskian to assist us find out whether two solutions were a fundamental set of solutions. Under this section we will look at the other app

Drug administration, A drug is administrated once every four hours. Let D(n...

A drug is administrated once every four hours. Let D(n) be the amount of the drug in the blood system at the nth interval. The body eliminates a certain fraction p of the drug duri

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd