Page 258 - Artificial Intellegence_v2.0_Class_11
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In this case, we create a frequency table using class interval, shown as follows:

                                           Class Interval     Tally         Frequency
                                               0-10                              0

                                               11-20            /                1
                                               21-30                             0
                                               31-40            //               2
                                               41-50          ////  /            6

                                               51-60         ///  ////           8
                                               61-70           ///               3
                                               71-80            /                1
                                               81-90           ////              4

                                              91-100                             0
                                               Total           25               25


              Graphs and Shapes of Distributions
              Data can be summarized through various methods such as data matrices, frequency tables, or graphs. In graphs, the
              data points are distributed throughout the chart. These distributions show the extent (dispersion, variability, scatter) of
              the data. The extension can be stretched (over a larger area) or compressed (over a narrower area).
              Here we learn about data distribution and the importance of the distribution. The shape of a distribution is described by
              its number of peaks and their symmetry, their tendency to skew, or their uniformity.
              The distribution shape shows:
              •  spread of the data i.e., scatter, variance, etc.
              •  where the mean lies in the data distribution

              •  range of the dataset
              Distributions that are skewed have more data points plotted on one side of the graph than on the other.
              Shapes of distribution are determined by factors such as:

              Number of Peaks
              The peaks are usually called modes. The mode represents that the data count is higher in some areas than in other areas
              of the graph.

              •   A unimodal distribution has a single peak or mode. The single peak can have different shapes (e.g., very high and
                  thin or short and fat). One of the most common types of unimodal distributions is the normal distribution (single
                  peak at the centre), also called the “bell curve” because its shape resembles a bell.

              •  A bimodal distribution has two peaks or modes.
              •  A multimodal distribution has three or more peaks.











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