Page 216 - DSOC404_METHODOLOGY_OF_SOCIAL_RESEARCH_ENGLISH

Methodology of Social Research

note 2. After this leaving the first frequency again the next two frequencies are added together and
their sum is written in column 3. For example, in above table the frequency 4 is the first
frequency, so leaving this the next two frequencies i.e. 2+5 =7 is written in column 3. if in
the end there is no pair the element is left out.
3. After this the three frequencies are added together and their sum is written in column 4,
for example 4+7+3=14, 2+5+9=16, etc. If in the end we cannot find three elements then it is
left out.
4. After this leaving the first frequency again the next three frequencies are added together
and their sum is written in column 5. For example, 7+3+2= 12. If in the end we cannot find
three elements then it is left out.
5. After this leaving the first two frequencies, third time again we write the sum of three
elements in column 6. For example: 3+2+5=10, 9+8+3= 20, etc. If in the end we cannot find
three elements then it is left out.
6. After this while doing the analysis we must keep in mind the frequencies of column 1 to 6.
the frequency that is highest in column 1, we will put a tick mark against that in column 7.
for example, in column 1 the frequency of 9 is the highest therefore, we will put a tick mark
against 9 in column 7. After this the frequency of which elements is highest in column 2,3,4,5,6
and that sum in column 1 we will put a tick in column 7. for example, in column 2 the sum
of 14 is highest, and this sum is of 5 and 9 in column 1 therefore, we will put a tick against 5
and 9 in column 7. in the same way the sum of 17 is the highest in column 3 and this sum is
of 9 and 8 in column 1. therefore, we will put atick against 9 and 8 in column 7.
7. in this way after doing the analysis, the frequency that has the highest ticks against them
in column 7, the value of that will be our mode, for example, in the above table the highest
6 ticks are against the frequency 9. therefore, the value of 9 i.e, 35 in the above table is the
mode.

Mode of continuous series
to find the mode of a continuous series firstly we need to find out the class-interval in which mode
is located by analysis. If there is more than one mode or we can find out the mode by analysis then
we need to find out the class-interval of mode by using the above technique as shown in the table.
thereafter the mode can be calculated by the given formula.
f − f
Mo = L + 1 i ×
2 f − f − 1 f 2
Where Mo = Mode
L = Lower limit of mode class-interval
i = the difference between the upper and lower limit
of mode class-interval.
f = frequency of mode class-interval
f = the frequency of class-interval before mode class-
1
interval
f = the frequency of class-interval after mode class-
2
interval

Example 15 in the table given below the marks of 40 students are listed. find the mode
by using inspection method and grouping method.

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