Monday, April 27, 2009

Whom Do You Believe: Me or the RPX Forwards?

RPX housing futures offer a different prediction than I do. Eric Nielsen of the University of Chicago offered this comment:


"I spent last year working in credit research at a large MBS hedge fund and as part of my job I investigated the RPX index, meeting with representatives of their company at several conferences.

In summary, I would be very suspicious of numbers coming from their index. Their methodology is quite strange and at least as of 10 months ago trade in the contracts was very light making the predictive power of the futures prices suspect.

On the plus side, at least historically their index tracks Case-Shiller quite closely. However, their index is substantially more volatile.

More information on how they compute their index can be found at this address:
http://www.radarlogic.com/white%20papers/The%20Radar%20Logic%20Index%20Methodology%20White%20Paper.pdf

Their index is based on the distribution of price-per-square- foot transactions in a given region over a given time interval. They do not differentiate between new and old housing stock, so their index is not constant quality.

Further, they report that their index is computed daily or monthly, but given the frequency with which transactions databases are updated this is not possible. I suspect they just use whatever data they have as of certain date, which means heterogenaity in county reporting speeds can bias their index."

Either way, it is still cheaper to buy a house via RPX (if you can do that) rather than from an actual homeowner.

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