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  Procedure testing of hypothesis 1.       Setting up of hypothesis – Null hypothesis and Alternative hypothesis. 2.       Defining the level of significance (α) 3.       Computation of test statistic  The test statistics is a statistic based on appropriate probability distribution. It is used to test                     whether the null hypothesis set up should be accepted or rejected. Z – Distribution: Use z- distribution under normal curve for large sample (i.e., if the sample size n≥    30). The Z – statistic is defined as 4.       Critical region or critical value. The rejection region or critical region is the region of the standard normal curve corresponding to a predetermined level of significance (α). The value of the sample statistics defines the region of acceptance and rejection is call...

  Inferential Statistics Definitions: Hypothesis : Hypothesis is a statement about the values of the population parameter. It is made on the basis of the information obtained by experimentation. Testing of hypothesis is a procedure for deciding whether to accept or reject the hypothesis. Procedures which enable us to decide whether to accept or reject hypothesis are called tests of hypothesis, also known as test of significance.   Statistical hypothesis : a statistical hypothesis is a statement about the parameters of one or more populations. Example: (i) The average IQ of normal human beings is 113. (ii) The teaching methods in both the schools are effective. There are two types of hypotheses. They are Null hypothesis and alternative hypothesis. N ull hypothesis: A null hypothesis is a statistical hypothesis formulated for the sole purpose of rejecting it. Example: if we wish to decide whether one procedure is better than the other, then we formulate ...

  OPERATION RESEARCH FUNDAMENTALS FOR BUSINESS OPERATION RESEARCH Operation Research  Operation Research is a discipline that helps to make better decisions in complex scenarios by the application of a set of advanced analytical methods.  It couples theories, results and theorems of mathematics , statistics and probability with its own theories and algorithms for problem solving Operation Research is also known as  • Decision Science • Management Science • Operation management • Quantitative Techniques

The values of a time series may be affected by the number of movements or fluctuations, which are its characteristics. The types of movements characterizing a time series are called components of time series or elements of a time series. These are four types Secular Trend  Seasonal Variations  Cyclical Variations  Irregular Variations  Secular Trend  Secular Trend is also called long term trend or simply trend. The secular trend refers to the general tendency of data to grow or decline over a long period of time. For example the population of India over years shows a definite rising tendency. The death rate in the country after independence shows a falling tendency because of advancement of literacy and medical facilities. Here long period of time does not mean as several years. Whether a particular period can be regarded as long period or not in the study of secular trend depends upon the nature of data. For example if we are studying the figures of sales of cloth ...