Unformatted text preview: ring this type of distribution is very
simple. We have just to count the number of times a particular
value is repeated, which is called the frequency of that class. In
order to facilitate counting prepare a column of tallies.
In another column, place all possible values of variable
from the lowest to the highest. Then put a bar (Vertical line)
opposite the particular value to which it relates.
To facilitate counting, blocks of five bars
are prepared
and some space is left in between each block. We finally count the
number of bars and get frequency.
Example 1:
In a survey of 40 families in a village, the number of children per
family was recorded and the following data obtained.
1
0
3
2
1
5
6
2
2
1
0
3
4
2
1
6
3
2
1
5
3
3
2
4
2
2
3
0
2
1
4
5
3
3
4
4
1
2
4
5
Represent the data in the form of a discrete frequency
distribution.
50 Solution:
Frequency distribution of the number of children Number of
Children
0 Tally
Marks Frequency
3 1
2
3 7
10
8 4
5
6 6
4
2
40 Total b) Continuous frequency distribution:
In this form of distribution refers to groups of values. This
becomes necessary in the case of some variables which can take
any fractional value and in which case an exact measurement is not
possible. Hence a discrete variable can be presented in the form of
a continuous frequency distribution.
Wage distribution of 100 employees
Weekly wages
(Rs)
50100
100150
150200
200250
250300
300350
350400
Total Number of
employees
4
12
22
33
16
8
5
100
51 4.3 Nature of class:
The following are some basic technical terms when a
continuous frequency distribution is formed or data are classified
according to class intervals.
a) Class limits:
The class limits are the lowest and the highest values that
can be included in the class. For example, take the class 3040.
The lowest value of the class is 30 and highest class is 40. The two
boundaries of class are known as the lower limits and the upper
limit of the class. The lower limit of a class is the value below
which there can be no item in the class. The upper limit of a class
is th...
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 Winter '08
 Moshiri
 Business, Statistics

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