# Linear regression

In advance I admit my statistical amateur status, but I still have numbers to crunch and a job to do so…

I have considered the sample model that uses linear regression on stock prices, etc. That model uses dates as the independent variable, x.

I am trying to do linear regression where x is not based on time but on throughput, hits on a web server, for example. The dependent variable would be- for instance- a measurement of CPU.

The other complication is that the contents of cells are dynamic, being fed by linked matrices, which are in turn fed by a datalink. I know that i am probably over-complicating the linkages, but I am just trying to tackle one obstacle at a time. Bottom line is: no cell value can be static.

So, taking one issue at a time, I have calculated linear regression but the independent value (x) is an item cell with the dependent value (y). X needs to be on the chart as the x axis, and y on the y axis. But with them both being in the same item group(?) I cannot chart them like that.

How do I rectify that?

Vince

Vince, I looked over your model and noted that there was 21 million cells which is impressive; however, it was too impressive for my laptop. I tried the solution I described below but I cannot verify for you that it worked.

What you might consider is creating a new matrix via a datalink that will take the x and y values and datalink them as categories plus what you want to plot as an item. If you set the selection on the datalink wizard correctly, this will be a dynamic datalink so as the values in the source matrix changes the “charting” matrix will change as well. I did something similiar at:

[url:37fjz8pl]http://www.quantrix.com/forums/showthread.php?t=307[/url:37fjz8pl]

I hope this works and please let me know your results. If not, maybe we can trim the model down data wise so that we I can work out a tested solution.

Steve

Here is the steps I took with the datalink wizard:

Select data source as two dimensional matrix data

Set your source matrix

Select the category that contains your x, y and plotting data (“Item” in your case?)

Select data destination as Multi-dimensional OLAP Analysis

Create new matrix

Select your columns to include (x, y and plotting data)

Set your x and y to category and plotting data to item (sort if necessary)

Set any summary choices

Set “Remove previously imported category items and data”

Hit finish (this is were I needed more horsepower)