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The interquartile range (IQR) can be calculated as:
        IQR = Q3 – Q1

        which is 160 – 60 = 100.

            20        40       60       80       100       110      120       140      160       180      200
                               Q1                          Q2                           Q3

        As reported on a weather report, the temperature ranges for the day are an important application of quartiles. If
        there are irregularities, they may have a big impact on the range values. The top and bottom 25 percentiles of the
        data points are thus preferred to be ignored in favour of the IQR. IQR is more resilient and a better reflection of the
        degree of dispersion in the data when there are irregularities.

        4.6. DECILES


        Decile is a technique that is used to divide a distribution into ten equivalent parts. When data is divided into
        deciles, a decile rank is allotted to each data point in order to sort the data into an ascending or descending order.
        Each section of the sorted data denotes 1/10 of the original sample or population. This ordering is done with the
        help of a scale from 1 to 10, where each successive value represents an increase of 10 percentage points. A decile
        has 10 categorical buckets, a quartile has 4, and a percentile has 100.
        In the fields of finance and economics, the concept of a decile is commonly used to analyse data. It can be used to
        check the performance of a portfolio in the field of finance.
        The higher the place in the decile ranking, the higher is the overall ranking. For example, a person getting 98
        percentiles in an exam would be placed in a decile ranking of 10. But, a person receiving 5 percentiles in the same
        exam would be placed in a decile ranking of 1.
        The formula for calculating decile is:
                  (n + 1)
        Di = i ×   10  Data
                   th
        Where:
               th
        i is the i  decile and can be represented as:
                            (n + 1)
         st
        1  Decile, D  = 1 ×   10  data
                             th
                   1
                             (n + 1)
        2  Decile, D  = 2 ×   10  data
         nd
                              th
                    2
        and so on
        n is the number of data in the population sample.
        Follow the given steps to calculate decile:
        Step 1  Find the number of data or variables in the sample or population which is denoted by n.
        Step 2  Now, arrange all the data or variables in the sample or population in ascending order.
        Step 3  Then, based on the decile that is to be find, calculate the decile by using the formula:
                  (n + 1)
        Di = i ×   10  Data
                   th
        Step 4  Finally, based on the decile value, find the corresponding variable from amongst the population data.
        Let us take an example to understand the concept in detail:
        Suppose we have 22 random numbers between 24 and 70. We want to represent them as deciles.

        The numbers are:
        [25, 33, 28, 45, 42, 36, 54, 68, 44, 35, 26, 37, 43, 55, 64, 65, 30, 39, 47, 52, 58, 66]



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