Regression analysis in Excel

Regression analysis is one of common need for data analysis. For this we need to install data analysis add in from Microsoft. If you are using first, follow the steps of installation (see the link). In Microsoft Excel 2003, this under tools. Click add ins. Then you can see list of add ins installed. Check data analysis and data analysis VBA.

With Data Analysis ToolPak installed we will be able to see Data analysis function under tool menu in Excel 2003. Click the data analysis you can select the regression analysis. Select regression analysis. 

Now we need to specify range of X and Y values and output area (most preferably in new worksheet). Specify input Y range, X range. For dignosis of regression model we will like to see residual plots and also normal probability plot. Check the appropriate boxes.   

Now OK will take you all the output needed in regression analysis:

You can change the plot to look them nicer (if you need to present).

Quick method without need of data analysis VBA: 

We can also get regression plot and equation with R square, using just scatter plot and adding the line to the plot and display linear regression equation. Such plot is useful in presentation of results.

For plotting from Excel read my another blog: 

http://excelgraphs.blogspot.com/