normal probability distribution curve

Introduction - The scientific methods of collection of data, its classification and application to commerce and everyday life is called statistics. A list of some important terms as follows: (i) ungrouped data (ii) tabulation of data (iii) range (iv) frequency (v) frequency distribution (..

In this chapter we have studied the method of evaluating probabilities of events relating to independent events and conditional events. We have also studied about random variables and their probability distributions, namely binomial distribution and Poisson h..

In a frequency distribution, the mid-value of each class is obtained. Then on the graph paper, the frequency is plotted against the corresponding mid-value. These points are joined by straight lines. These straight lines may be extended in both directions to meet the X - axis to form a po..

(i) The class intervals are made continuous and then the histogram is constructed. (ii) A kink or a zig - zag curve is shown near the origin. It indicates that the scale along the horizontal axis does not start at the origin. (iii) The horizontal scale and vertical scale need not..

If x is a discrete random variable assuming the values x 1 , x 2 , x 3 ,….,x n with probabilities p 1 , p 2 , p 3 ,…., p n respectively then (x 1 ,p 1 ), (x 2 , p 2 ),…(x n , p n ) defines a probability distribution of X. Mathematical Expecta..

Poisson distribution is a limiting process of binomial distribution. Poisson distribution occurs when there are events which do not occur as outcomes of a definite number of outcomes. Poisson distribution is used under the following conditions: ..

Poisson Distribution - Poisson distribution is a limiting process of binomial distribution. Poisson distribution occurs when there are events which do not occur as outcomes of a definite number of outcomes. Poisson distribution is used under the fol..

Binomial Distribution - A trial, which has only two outcomes i.e., "a success" or "a failure", is called a Bernoulli trial. Let X be the number of successes in a Bernoulli trial, then X can take 0 or 1 and P(X =1) = p = "probability of a success" P(X = 0) = 1 - p = q = "pro..

Frequency Distribution - A teacher gave a test to a class of 26 students. The maximum mark is 5. The marks obtained by the pupils are: Such data as above is called ungrouped (or raw) data. We may arrange the marks in ascending or descending order. The data so represented is called an arra..

where l is a finite number and is equal to np. The sum of the probabilities P(X = r) or simply P(r) for r = 0, 1, 2, is 1. This can be seen by putting r = 0, 1, 2, in (4) and adding all the probabilities. Also, each of the probabilities is a non-negative fraction. This..