Thursday, December 4, 2008

Case-Shiller Home Price Charting and Visualization Application

My family has been in the market for a house for several years now. A home in Boston is a huge investment, so naturally I've been curious about where home prices are headed. The S&P/Case-Shiller Home Price Indices measure home prices calculated from data on repeat sales of single family homes. Until recently, at the end of each month I would download the numbers in the form of an Excel spreadsheet, and manually chart and analyze the data. Finally, a couple of weekends ago I developed a simple Flex Application that uses the Advanced Data Visualization Framework to generate line graphs of home prices relative to 2000, month over month changes, and year over year changes.

So go check out the Lightsblue Home Price Application.

Alternatively, you can subscribe to the Lightsblue Home Price Feed, which will be updated when new features or data is added. The latest Case-Shiller home price data is currently published the last Tuesday of every month by S&P.


bostonbubble said...

Looks nice. If you happen to be taking feature requests, it would also be nice to have an option for inflation adjusted values and an option for displaying futures contracts too.

nvihinen said...

Perhaps if I get some time over the next couple of weekends, I'll add inflation adjusted values and futures.

David M Gordon / The Deipnosophist said...

Hi, Noah,

You have created a visually appealing and helpful visual display. Alas, the data remains raw; it lacks context.

More helpful, perhaps, would be to compare, or have the ability interactively to compare, the x and y axes of the current decline with previous declines. For example, how does the current decline of x percent in y time measure up against previous declines? Does the pace of the decline offer insight to the depth of this, or any, decline? Does the depth of a decline offer insight into how long a decline will continue?, how soon before prices stabilize?, how soon before prices rise? Etc.

X and Y axes are often shown, but rarely used (correctly); you have created a tool that could be extraordinarily useful, even seminal.

I fear, though, that the process of including all the data such an endeavour would require would prove equally exhausting as it must be exhaustive to provide the proper framework and context. But you have shown you can do it, if anyone can.

Thank you for the opportunity to comment.