Prosper's blog entry is the biggest load of malarcky I've ever seen. Some of you have already pointed out some of the many problems. here are a few more:
It’s unfortunate that the author’s data analysis and perspective relied almost entirely on a hodgepodge of anonymous sources.
Huh? Prosper, better than anyone, knows exactly who the so-called anonymous sources are. For example, Prosper knows Fred93's real name, address, phone number, social security number, checking account number, etc. Similarly, is Prosper really claiming that Eric's is an "anonymous source" considering that it takes Prosper's OWN data and makes it available to the public and has done so for almost as long as Prosper has been around?
Although this return is negative, put in the context of the largest recession in generations, and the performance of other asset classes during the same time period, this paints a very different and more accurate picture of how lenders have fared on Prosper.
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[A] low single digit loss for Prosper lenders in the context of the worst recession since the Great Depression shows great promise for peer-to-peer lending as an alternative asset class for investors. Even a broad index like the S&P 500 saw an annualized loss of 6% in the past three years. Most individual investors have experienced performance substantially worse than this in their investment portfolios and 401k accounts.
This repeats a fallacy I have repeatedly pointed out. Yes, the S&P tanked badly in 2008. And yes, Prosper lenders' losses in 2008 were no doubt dwarfed by their stock losses. But guess what? The defaulted Prosper loans are worthless FOREVER. But those stocks regained most of their losses in 2009. If stock investors hold on to their shares, at some point (most likely this year) the losses will all be erased and stock investors will have profits. But no matter how long we hold on to our defaulted loans, they will NEVER bounce back -- they will ALWAYS be WORTHLESS.
The early results from the new rating system are excellent. Prosper is estimating returns for lenders above 10% for loans originated since our July re-launch and the early data supports these expectations.
Uh huh. Just like Prosper estimated similar returns for lenders using its much vaunted Experian default rates? Sure, this time it will be different.

Uh huh.
Below is a graph comparing the delinquency performance of loans originated by year with the loans originated in the third quarter of 2009. As you can see, the proportion of loans that are 31 to 120 days past due for the loans originated under the new rating system are dramatically lower.[/quote]
Let me see if I have this straight -- Prosper is comparing the percentage of bad loans originated in earlier years with the percentage of such loans from 3Q09??? Those loans are a mere 3.5-6.5 months old, so they have only had 3-6 payments even due yet. And to be at least 31 dpd, they would have had to miss the second through fifth payments! No duh that this subset of extremely young loans isn't doing badly yet.
Prosper was launched to the public in February of 2006 and was about 18 months old when the credit crisis turned our economy upside down.
So why is it that Fred93's charts showed even back then that Prosper loans were headed for a 40% default rate?