Number of data points for statistical graph

[froggy19]

Hi,

I am doing a excel program currently and the program is to return some graphs(eg. normal, lognormal, weibull etc) based on some datas. However, i would like to find out if there is any requirements or rather the number of data points i would need in order for my graph to be "accurate" or "precise"?


Cheers.

[Code Doc]

You will need at least three points for Excel to show any type of a curve. The more points you add, the more accurate the curve will depict the relationship. Even Excel cannot make bricks without straw.

At the extreme, any more than 30 points is probably a waste (the normal distribution rule).

[froggy19]

Hi,

thank you for the help (",)

Cheers

[froggy19]

Hi Code_Doc,

you mention "At the extreme, any more than 30 points is probably a waste (the normal distribution rule)." Is there any article available on the internet to read more about this. I dno't seems to be able to find them

Cheers

[Rassis]

The answer to your question and any further questions you may have on stats can be found in this excellent e-book:

http://www.statsoft.com/textbook/stathome.html