Continuous Frequency Distribution, Mean deviation about mean - Statistics Video Lecture - Class 11

hello friends this video statistics part
12 is brought to you by exam viacom no
more fear from exam before watching this
video please make sure that you have
watched statistics part 1 - part 11
let's discuss continuous frequency
distribution in continuous frequency
distribution the data is classified into
different class intervals without gas
please note without gaps for example
when I'm saying that is to 10 to 20 the
next value is 20 to 30 the next is 30 to
40 the next is 40 to 50 that will be 66
to 70 there is no gap if we have data
like this 10 to 20 21 to 30 31 to 40
this is not continuous so for what
distribution of our frequency
distribution to be continuous first
thing the class interval has to be there
which equal for example here it is 10
interval 0 sort n the class interval is
there some class interval is there and
there is no gap there is no gap it is 10
20 this is 20 30 there is no gap and the
class interval is a such kind of
distribution is called continuous
frequency distribution now in this case
we have two dough's first doubters if it
is a class interval is happened 10 to 20
what value should we take for X I for
example in the past questions we had
this is Fi and we used to have X I a
fixed value but here is an interval
8 10 to 20 20 30 so in case in this case
so we were to take the mean on this so
in this case X I will be 10 plus 25 that
is 30 by 2 in this case 20 plus 30 by 2
50 by 2 25 in this case 30 plus 45 to 70
by 2 is 25 in this case 40 plus T by 2
90 by 2 45 in this case 50 plus 60 by 2
that is 55 in this case 60 plus 70 by 2
65 in this
same facility by 2 this is the value of
x iyb idli generally actually if you
want to find mean deviation about mean
on me those kind of thing about me
second thing second thought we can have
if you see 20 is here also for these
heroes so if you have the value 20 it is
way in a bitch bucket it will be in this
bucket
what is bucket so the rule a er is the
lower limit right it is always included
we include lower limit and the upper
limit the upper limit is always is to
let me repeat the rules once again the
lower limit is always included and the
upper limit is always excluded so in
this case 20 will not be in this folder
because right these always straight so
this will have value strong ten to
nineteen point nine nine nine nine nine
nine at this point this will be this
mosque from twenty to twenty nine point
nine nine nine nine tell me in the box
to let you see box two will happen
similarly for 40 if you want to ask for
tea will be in this or this we know that
this boss will be have thirty to thirty
point nine nine nine nine forty will not
be there because the upper limit is
always excluded and the lower limit is
of is included so here lower limit is
infinity so 40 may be in this box then
let me repeat the two doubts we had
first thing how we find the value of x I
says it is range so we'll just take the
mean of the maximum value so the
exercise will be 10 plus 20 by two 15 25
35 and so on similarly whether the
values are included or not the rule is
the lower limit is all the discipline
and the upper limit is always excluded
the lower limit is included the lower
limit is included and the limit is
excluded please remember lower limit is
included in the upper limit is excluded
that's found if I you repeat once again
in continuous frequency this
we have class intervals in different
class intervals without gaps there is a
first thing with respective frequencies
lower limit has included upper limit is
excluded and fine excise we take the
mean of the upper and lower limit of the
classroom now if you want to find the
mean deviation about me please remember
mean division about me not median the
formula will change for continuous
distribution mean division about mean
first we have to find the mean correct
because if you want to find mean
division about a point a we have to
first find the point a so in this case
we have you first find the point the
mean to find the mean we'll use the same
formula which we have used in the past
Sigma fi x I by Sigma fi and X I is
nothing here if you see is the class
interval if you have example 30 to 40 40
to 50 should be a de the mean of this
sorry to 30 plus 40 why do you do it if
I in this case 40 plus 50 by do so XIV
no frequency is given so we get the mean
once we have the mean you do the same
formula which we have Sigma fi into
instead of X is X I - mean mod by Sigma
I correct everything is same but just
here we have to first find the value of
x I because the range will be given and
from that range we have to find the
value of x I will take my exam thank you
visit exam viacom to watch free
education videos try free online tests
get the best quality study materials
study from the best tutors and mentors
and much more thanks and sorry