Meaning of Goodness of fit test: We find out which distribution fits the sample data the most. And this is achieved using chi-square distribution (Snedecor and Cochran, 1989). How to apply: There are 4 steps to follow: State the hypothesis: Data follows a distribution or not Criteria to reject null hypothesis: if Χ 2 > Χ 2 (k,1-α) then reject null hypothesis. Analyze sample data: Compute the chi-square value using below formula: ∑(Oi- Ei) 2 /Ei : Oi is observed frequency and Ei is expected frequency Interpret the results: Declare the results after comparing the values of Χ 2 and Χ 2 (k,1-α), where k is degree of freedom and α is significance level. Degree of Freedom: It is = n - 1 - m m: number of parameter in the distribution. So in case of normal distribution m is 2 ( μ ,α) and in case of poisson dist. m is = 1 ( λ). Example 1: Goodness of fit test for Normal Distribution Year wise d...
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