HOUMBA-28 Stepwise Regression

An Excel add-in that runs forward selection, backward elimination and stepwise regression, then writes a report in the same layout as Excel's Data Analysis > Regression tool (with Standard Error shown as RMSE). Variables enter and leave on |T-Stat| ≥ 2 by default, or on p-values if you prefer.

• Works in Excel for the web, Windows and Mac.
• No macros, no Trust Center settings, nothing to install on your computer.
• Your data never leaves your workbook.

Install page: https://cranksrust.github.io/stepwise-regression-excel/

Install (students)

The add-in is not in the Office Add-ins store yet, so it is installed from a small file called HOUMBA-28-Stepwise-Regression.xml (Microsoft calls this a manifest: it tells Excel the add-in's name, button and web address). This takes about two minutes and only needs to be done once per browser or computer.

Step 1: Download the add-in file

1. Go to https://cranksrust.github.io/stepwise-regression-excel/
2. Click Download the add-in file and save HOUMBA-28-Stepwise-Regression.xml somewhere easy to find, such as Downloads.

Step 2: Add it to Excel

Excel for the web (recommended, works for everyone)

1. Go to office.com and open any workbook.
2. Open Add-ins. Where it is depends on your window width:
   • Wide window: Home tab, Add-ins button at the right end of the ribbon.
   • Narrow window: click the ⋯ at the right end of the Home ribbon, or use the Insert tab, Add-ins.
3. Click More Add-ins (on some versions, Advanced).
4. Open the My Add-ins tab and click Upload My Add-in near the top right.
5. Click Browse, choose HOUMBA-28-Stepwise-Regression.xml, and click Upload.
6. A Stepwise Regression button appears on the Home tab (in a narrow window, it may be under the ⋯).

Excel for Mac

1. Quit Excel.
2. In Finder, press Cmd+Shift+G, paste ~/Library/Containers/com.microsoft.Excel/Data/Documents/wef and press Return. If it says the folder does not exist, go to ~/Library/Containers/com.microsoft.Excel/Data/Documents and create a folder named wef.
3. Copy HOUMBA-28-Stepwise-Regression.xml into the wef folder.
4. Open Excel and a workbook, then go to Home > Add-ins (or Insert > Add-ins > My Add-ins). Stepwise Regression is listed under the developer or shared add-ins section. Click it once and the button appears on the Home tab.

Excel for Windows (desktop)

Go to Home > Add-ins > More Add-ins > My Add-ins. If Upload My Add-in is shown, follow steps 4 to 6 above. If it is not, use Excel for the web.

Step 3: Run a regression

1. Click Stepwise Regression on the Home tab. A panel opens on the right.
2. Select your Y column, including its label cell, and click Use selection next to Y range.
3. Select your X columns, including their label cells, and click Use selection next to X range. Hold Ctrl (Cmd on Mac) to pick columns that are not next to each other.
4. Leave First row contains labels ticked if you included the labels.
5. Choose the Method (Stepwise is the default) and Criterion (T-Stat, entering and removing at |T-Stat| = 2.00, is the default).
6. Click Run regression. The report opens on a new sheet named Stepwise.

Try it with sample data

Download home-prices.xlsx: 60 fictional home sales with eight candidate predictors. Use Y A1:A61 and X B1:I61 on the Home Prices sheet, then run Forward, Backward and Stepwise and compare the steps.

Step	Forward	Backward	Stepwise
Start	intercept only	all 8	intercept only
1	+ TAX_ASSESSED	− GARAGE	+ TAX_ASSESSED
2	+ AGE	− BATHROOMS	+ AGE
3	+ SQFT	− BEDROOMS	+ SQFT
4	+ MILES_DOWNTOWN	− TAX_ASSESSED	+ MILES_DOWNTOWN
5	+ SCHOOL_RATING		− TAX_ASSESSED
6			+ SCHOOL_RATING
Final R Square	0.9082 (5 terms)	0.9070 (4 terms)	0.9070 (4 terms)

TAX_ASSESSED looks like the best single predictor, but it only echoes the real drivers. Stepwise drops it once they are in the model (its T-Stat falls to 1.58). Forward selection never re-checks, so it ends with TAX_ASSESSED still in the model at a T-Stat of −0.85.

If something goes wrong

Problem	Fix
No Add-ins button	The window is too narrow. Check under ⋯ on the Home ribbon or the Insert tab, or widen the window.
Upload My Add-in is missing or greyed out	Your school or work account may block custom add-ins. Sign in to office.com with a personal Microsoft account and try again.
The button disappeared	In Excel for the web, uploaded add-ins are remembered per browser. Upload the add-in file again.
"Every X column must start and end on the same rows as Y"	Select the same rows for Y and X, for example A4:A48 and B4:F48.
"The model with every predictor cannot be estimated"	Two X columns carry the same information (for example one is a fixed number minus the other). Remove one, or use Forward or Stepwise.

More help: https://cranksrust.github.io/stepwise-regression-excel/support.html

About

Built by the University of Texas at Austin's MBA at Houston Class of '28 for Professor Tom Sager's BA 286T Statistics course, Fall 2026.

• MAINTAINING.md: how the add-in works, hosting, tests and publishing to the Office Add-ins store.
• vba/: the original VBA (.xlam) version for desktop Excel, kept as a backup.
• Released under the MIT License.