# Create a function from a data set when there is one independent variable and 3 dependent

I have a data set which consists of 1.Number of users, 2.Cpu usage, 3.Ram Usage, 4.Response time,

The way I understand it Number of users is my independent variable. Is there a way, a method, or a program to help me create a function that expresses Response time in terms of cpu usage, ram usage and number of usage? I believe regression is the way to go but I cannot find any example using Google. Below there is a graph that show all my values

Any help would be much appreciated

UPDATE: Is it better to assume that only response time is dependent and the other 3 independent? If so what method should I use?

You could definitely try Linear Regression to model response time as a linear function of {Number of users, Cpu usage, Ram Usage}.

But, first you may want to read-up the Wikipedia article linked above. If your data can fit into a simple Excel spreadsheet - then linear regression can be done from with-in Excel using the data analysis pack.

With regards to:

Is it better to assume that only response time is dependent and the other 3 independent? If so what method should I use?

You should ask yourself - what is the quantity I'm interested in predicting? or understanding how one quantity differs with a change in set of other explanatory quantities.

For ex: If you are concerned about response time and would like to understand how response time behaves with respect to {Number of users, Cpu usage, Ram Usage} variables then response time is indeed your target/dependent variable of interest.

• I have tried excel's data analysis but the output is not validating against the data. Yes I indeed want to understand how response time behaves so thanks for making it clear to me. Commented Feb 5, 2014 at 12:02