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1.5.5. Differences and Relationship among Basic Measures of Central Tendency

            There is a huge difference between basic measures of central tendency, i.e., mean, median and mode. These shall
            be equal in case of normal distribution. They will be almost equal in case of slightly positive or negatively skewed
            distribution.
            But, there is also a relationship between mean, median, and mode. We term this relationship as the empirical
            relationship.

            Relationship Between Mean, Median, and Mode
            We will recognise the empirical relationship between mean, median, and mode by using a frequency distribution
            graph. We can divide the relationship into four different cases:

            1.  In the case of a moderately skewed distribution, i.e., in general, the difference between mean and mode is equal
              to three times the difference between the mean and median.

                              Thus, the empirical relationship as Mean – Mode = 3 (Mean – Median)
            2.  In the case of a frequency distribution that has a symmetrical frequency curve, the empirical relation states that
              mean = median = mode.





                                       Frequency                    Mean = Median = Mode










                                                                x Variable
            3. In the case of a positively skewed frequency distribution curve, mean > median > mode






                                                             Mode
                                                             Median

                                                              Mean







            4. In the case of negatively skewed frequency distribution curve, mean < median < mode





                                                      Mode
                                                     Median
                                                      Mean








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