Page 121 - Data Science class 10
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Example 1.2: Consider a farewell event of mixed classes having only ten students. You have conducted the survey
            by asking students if they like eating pizza. You record the data in the format given below.

                                       Name of student         Age           Likes Pizza?

                                        Participant no 1       18              <Yes>
                                        Participant no 2        6                No
                                        Participant no 3       13              <Yes>

                                        Participant no 4        9                No
                                        Participant no 5       12              <Yes>
                                        Participant no 6       14              <Yes>

                                        Participant no 7       19              <Yes>
                                        Participant no 8        8                No
                                        Participant no 9       16                No

                                       Participant no 10       12              <Yes>
            If you now break down the data into age categories of (5 – 10 years), (10 – 15 years), and (15 – 20 years), and plot
            the number of students who like and dislike pizzas, then the table would look like below:

                                        Age Group         Likes Pizza    Does not like pizza

                                          5 to 10             0                  3
                                         10 to 15             4                  0
                                         15 to 20             2                  1

            The row category in this example is “5-10 years”, “10-15 years” and “15-20 years”. The column category is their
            choice “Likes pizza” or “Does not like pizza”. Each cell tells us the number (or frequency) of the students. There is a
            lot of information that we can get from this small table. For example,

            Q. How many students were questioned?
            Answer: 10
            Q. How many students liked pizzas?
            Answer: 6

            Q. In which age group do students like pizzas the most?
            Answer: 10 – 15

            Let us now have a look at another example:
            Example 1.3: Two-way frequency tables show how many data points fit in each category. The columns of the table
            tell us whether the student is a male or a female. The rows of the table tell us whether the student prefers dogs,
            cats, or doesn't have a preference. Each cell tells us the number (or frequency) of students.

                                          Preference          Male             Female

                                          Prefer cats          36                22
                                          Prefer dogs           8                26

                                        No preference           2                6
                                            Total              46                54




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