He co-founded Case Shiller Weiss (CSW) in 1991 to increase market awareness of ongoing price changes in residential real estate. CSW used the new indexing technique from a highly regarded academic paper to create the S&P
Case-Shiller index. Following this creation, CSW published forecasts of the Case-Shiller indexes in
The Wall Street Journal for over five years. In 1993 he co-authored a paper with
Karl Case and
Robert Shiller "Index-Based Futures and Options Markets in Real Estate", in
The Journal of Portfolio Management. The paper defines and analyzes a method to hedge and invest in home prices. In 2004
Chicago Mercantile Exchange launched home price futures based on the Case-Shiller indexes. In 1995 Weiss led the development of the CASA automated home valuation service. In 1997, Weiss conceived of a new financial structure enabling equity market investors to hedge or invest in home prices and other economic indexes. Weiss named the structure the Proxy Asset Data Processor and along with Shiller received two US patents, 5987435 and 6513020, for these inventions. They founded Macro Securities to commercialize these inventions. Securities under these patents have traded on the American Stock Exchange (UOY and DOY) and the New York Stock Exchange (UMM and DMM). A major uninsured home-ownership risk is the loss of home value due to market declines. In 1999 in collaboration with Robert Shiller, he published "Home Equity Insurance" in the
Journal of Real Estate Finance and Economics to address this subject. During sale of CSW to Fiserv, Weiss observed the extent to which smaller assets are worth less, for each dollar they earn, than larger more liquid assets; therefore
liquid assets generate lower income per dollar invested. Owners of the smaller assets could benefit from higher prices if some of their cash flows were aggregated into a larger more liquid fund. Weiss patented Common Index Securities – US patents 7155468 and 7716106 – financing structures that generate liquid and therefore value enhanced investments by aggregating
cash flows from smaller assets. This solution applies to any asset class whose value or earnings can be reliably indexed. In 2007, Weiss founded Market Shield Capital to commercialize Market Shield funds and Market Shield Mortgage loans based on the structure called Common Index Securities that Weiss patented in 2006. Weiss founded Weiss Analytics and currently serves as the CEO. WA aims to mitigate the financial risk of home ownership through 90 million repeat sales indexes, one for each house in the US, through the use of big data and
parallel computing techniques. This approach presents home price dynamics at the house level or any user defined aggregation. Instead of arbitrary market definitions such as
metro area, users can define their own markets such as "all houses with a current value above $500,000 within a 50-mile radius of the Statue of Liberty". This definition of new sub-markets leads to new insights. == Writings ==