Page 122 - Data Science class 10
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Example 1.4: A survey of eighty people (40 men and 40 women) was taken on what genre of movie they would
        choose to watch, and the following responses were recorded:
           • 12 men preferred comedy/family sas-bahu movies.
           • 12 men preferred action movies.
           • 16 men preferred horror movies.

           • 22 women preferred comedy/family sas-bahu movies.
           • 11 women preferred action movies.
           • 7 women preferred horror movies.
        The information collected is used to build the following two-way table:


                             Category      Comedy         Action       Horror         Total

                               Men            12            12           16            40
                              Woman           22            11            7            40
                               Total          34            23           23            80


        1.4.1. Interpreting Two-way Frequency Tables
        The entries in the table are counts. The table has numerous features:
           • Categories are in the left column and top row.

           • The counts are located in the centre of the table.
           • The totals are at the end of each row and column.
           • A sum of all counts (a total) is placed at the bottom right.

        For example, in the table given below, the rows of the table tell us whether it's a male or a female and the columns
        of the table tell us if they own a car or not. Each cell tells us the number (or frequency) of people. For example, 20
        females own a car.

                                  Category      Owns a car  Don’t own a car     Total

                                     Men           55              5              60
                                   Woman           20              40             60

                                    Total          75              45            120


          Activity         1


           Record how many of your near and dear ones like cricket and how many of them like football. Create a
           two-way relative frequency table with the data.



        1.4.2. Two-way Relative Frequency Table

        The two-way frequency type of table and the two-way relative frequency type of table are extremely similar. The
        main difference is that, here we take percentages rather than numbers. Tables of two-way relative frequency show
        the percentage of data points that fall into each group. Depending on the context of the issue, you can use either
        row relative frequencies or column relative frequencies.
        Let us see the below two-way table recording preferences of male and female architecture students with regard to
        their choice of the subject as Landscaping or Interior Decoration.
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