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Symmetry
                 Distribution is symmetric if its left half forms a mirror image of its right half.



















                                                    -4   -3  -2  -1  0    1   2   3    4

                                                       Symmetric          U shaped













                                                   10      20      30        40      50



                 Skewness
                 Skewness is a measure of a distribution's symmetry. The mode of a distribution is its highest point. If the tail on one side
                 of the mode is fatter or longer than the tail on the other, the distribution is skewed, i.e., it is asymmetrical.

                 A distribution that is not symmetric has values that tend to be more spread out on one side of the graph than on the
                 other. In such a case, we say that the distribution is skewed. There are three types of distributions which are left-skewed
                 distribution, right-skewed distribution and symmetry distribution.



                                     Left-skewed         Right-skewed                            Symmetric
                        Outliers                                           Outliers
                         at low                                             at high
                         values                                             values





                                  Mean        Mode     Mean       Mode                    Mode = Mean = Median
                                       Median               Median

                 Let’s observe how these distributions look when you use histograms.


                 Left-skewed Distribution
                 A negative skew in an asymmetrical distribution where the tail on the left side is longer than the tail on the right is known
                 as left-skewed distribution. It is also called negative-skewed. In left-skewed distribution, the values are more spread out
                 on the left side. The median and mean are less than the mode.

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