# Thread: Quartile and Standard deviation

1. ## Quartile and Standard deviation

Here is the data

15 12.8 11.5 14.5 13.6 14.5 10.5 10.7 10.8 14.1
15.1 10.3 15 10.3 14.5 14.9 11.3 14.3 12.6 14.7
10.4 10.4 15 10.1 15 12.4 12.5 12 12.1 14.8
10.1 15 12.9 14.7 14.9 15.1 11 14 10.2 15.3
14.8 14.4 14.9 10.5 10.9 13.7 15.1 13.1 14.4 12.7
10.3 15.2 15.1 10.8 13.9 11.8 10.5 15.1 15.3 15.1
11.2 13.5 12.9 14.8 13.8 14.5 15.2 15.5 14.9 11.4
14.7 14 10.7 10.7 14.8 10.9 11.4 14.6 10.1 14.4
15 11.7 13.9 13.8 10.6 13.9 15.8 10.6 15.4 14
15.4 15 15.7 15.3 11.7 10.4 15.3 11.5 10.4 10.3

How can i find the standard and quartile deviation ?
the method shown in wikipedia about standard deviation is very lengthy.

Also i want to know that the question states that find the GROUPING ERROR in results of mean, median and mode ?
How to find it ?

2. ## Re: Quartile and Standard deviation

Originally Posted by haftakhan
Here is the data

15 12.8 11.5 14.5 13.6 14.5 10.5 10.7 10.8 14.1
15.1 10.3 15 10.3 14.5 14.9 11.3 14.3 12.6 14.7
10.4 10.4 15 10.1 15 12.4 12.5 12 12.1 14.8
10.1 15 12.9 14.7 14.9 15.1 11 14 10.2 15.3
14.8 14.4 14.9 10.5 10.9 13.7 15.1 13.1 14.4 12.7
10.3 15.2 15.1 10.8 13.9 11.8 10.5 15.1 15.3 15.1
11.2 13.5 12.9 14.8 13.8 14.5 15.2 15.5 14.9 11.4
14.7 14 10.7 10.7 14.8 10.9 11.4 14.6 10.1 14.4
15 11.7 13.9 13.8 10.6 13.9 15.8 10.6 15.4 14
15.4 15 15.7 15.3 11.7 10.4 15.3 11.5 10.4 10.3

How can i find the standard and quartile deviation ?
the method shown in wikipedia about standard deviation is very lengthy.

Also i want to know that the question states that find the GROUPING ERROR in results of mean, median and mode ?
How to find it ?
First of all, is this data from a population or from a sample?

3. ## Re: Quartile and Standard deviation

Originally Posted by haftakhan
Here is the data

15 12.8 11.5 14.5 13.6 14.5 10.5 10.7 10.8 14.1
15.1 10.3 15 10.3 14.5 14.9 11.3 14.3 12.6 14.7
10.4 10.4 15 10.1 15 12.4 12.5 12 12.1 14.8
10.1 15 12.9 14.7 14.9 15.1 11 14 10.2 15.3
14.8 14.4 14.9 10.5 10.9 13.7 15.1 13.1 14.4 12.7
10.3 15.2 15.1 10.8 13.9 11.8 10.5 15.1 15.3 15.1
11.2 13.5 12.9 14.8 13.8 14.5 15.2 15.5 14.9 11.4
14.7 14 10.7 10.7 14.8 10.9 11.4 14.6 10.1 14.4
15 11.7 13.9 13.8 10.6 13.9 15.8 10.6 15.4 14
15.4 15 15.7 15.3 11.7 10.4 15.3 11.5 10.4 10.3

How can i find the standard and quartile deviation ?
the method shown in wikipedia about standard deviation is very lengthy.

Also i want to know that the question states that find the GROUPING ERROR in results of mean, median and mode ?
How to find it ?
For standard deviation:

Put the data into a spread sheet (all in one column), then add extra columns and cells to perform the calculations, or use the built in functions.

CB

4. ## Re: Quartile and Standard deviation

the question states about this data that its the length of 100 trouts in millimeter. i have calculated quartile deviation and now i want to know how to answer this part
find the GROUPING ERROR in results of mean, median and mode ?