Hello frndz,
today we will learn about Descriptive Statistics..
:- Average: The average of n number is defined as the sum of the n numbers divided by n.
For eg. the average of 6,4,7,10 and 4 is (6+4+7+10+4)/5 = 31/5 = 6.2
;- Median: To calculate the median of n numbers, first order the numbers from least to greatest; if n is odd, the median is the middle number.
For eg. the median of 6,4,7,10,4
step 1: first order it form least to greatest - 4,4,6,7,10
step 2: find the middle number i.e. 6
So median is 6
whereas, if n is even, the median is the average of the two middle numbers.
For eg. the median of 4,6,6,8,9,12 = (6+8)/2 = 7
(Note: if n is odd, median is (n+1)/2; else the average of n/2 and n/2 + 1)
:- It is not always true that half of the data in a series is less than median and half of the data is more than the median.
For eg. 3,5,7,7,7,7,7,7,8,9,9,9,9,10,10
Here the median is 7, but only 2/15 of the data is less than the median.
:- Mode; The mode of a list of numbers is the number that occurs most frequently in the list.
For eg. mode of 1,3,6,4,3,5 is 3 (occurs twice)
(Note: A list of numbers may have more than one mode.)
:- Range: Range is defined as the greatest value minus the least value.
For eg. the range of 11,10,5,13,21 is
21-5 = 16
:- Standard deviation: To calculate standard deviation;
step 1: find the arithmetic mean (average)
step 2: find the difference between the mean and each of the n numbers
step 3: square each of the differences
step 4: find the average of the squared differences
step 5: take the non negative square root of this average
For eg. standard deviation of 0,7,8,10,10
step 1: average = 7
step 2: differences = -7,0,1,3,3
step 3: square of differences = 49,0,1,9,9
step 4: average of step 3 = 68/5 = 13.6
step 5: square root of step 4 = 3.7
So S.D = 3.7
(Note: the more data are spread away from the mean, the greater the standard deviation and same as vice-versa).
Okie guys, keep practice on!! catch u soon.....
Er. Ankur Garg
garg.ankur6@gmail.com
today we will learn about Descriptive Statistics..
:- Average: The average of n number is defined as the sum of the n numbers divided by n.
For eg. the average of 6,4,7,10 and 4 is (6+4+7+10+4)/5 = 31/5 = 6.2
;- Median: To calculate the median of n numbers, first order the numbers from least to greatest; if n is odd, the median is the middle number.
For eg. the median of 6,4,7,10,4
step 1: first order it form least to greatest - 4,4,6,7,10
step 2: find the middle number i.e. 6
So median is 6
whereas, if n is even, the median is the average of the two middle numbers.
For eg. the median of 4,6,6,8,9,12 = (6+8)/2 = 7
(Note: if n is odd, median is (n+1)/2; else the average of n/2 and n/2 + 1)
:- It is not always true that half of the data in a series is less than median and half of the data is more than the median.
For eg. 3,5,7,7,7,7,7,7,8,9,9,9,9,10,10
Here the median is 7, but only 2/15 of the data is less than the median.
:- Mode; The mode of a list of numbers is the number that occurs most frequently in the list.
For eg. mode of 1,3,6,4,3,5 is 3 (occurs twice)
(Note: A list of numbers may have more than one mode.)
:- Range: Range is defined as the greatest value minus the least value.
For eg. the range of 11,10,5,13,21 is
21-5 = 16
:- Standard deviation: To calculate standard deviation;
step 1: find the arithmetic mean (average)
step 2: find the difference between the mean and each of the n numbers
step 3: square each of the differences
step 4: find the average of the squared differences
step 5: take the non negative square root of this average
For eg. standard deviation of 0,7,8,10,10
step 1: average = 7
step 2: differences = -7,0,1,3,3
step 3: square of differences = 49,0,1,9,9
step 4: average of step 3 = 68/5 = 13.6
step 5: square root of step 4 = 3.7
So S.D = 3.7
(Note: the more data are spread away from the mean, the greater the standard deviation and same as vice-versa).
Okie guys, keep practice on!! catch u soon.....
Er. Ankur Garg
garg.ankur6@gmail.com
No comments:
Post a Comment