Saturday, August 20, 2011

A look at Prosper's 2008 Loans

Previously I published a list of words which did poorly in pre-2008 loans and words that did well in pre-2008 loans. I wanted to see if those lists could predict what would happen in 2008 loans on Prosper.

I created a new value, WordValue, which will become negative if a loan has more words which had previously failed in it and become positive if a loan has more words which had previously succeeded in it. (Additional description of the value is below.)

Suffice it to say, I expected that lower WordValues would repay less often than higher WordValues. It turns out that this was not the case for 2008 loans:

DescriptionPaidRecoveredNever Recovered
2008, D, All49.8%50.7%34.7%
2008, D, WordValue <-150.9%51.7%34.2%
2008, D, WordValue >= -147.5%48.3%35.8%
2008, E, WordValue < -144.7%45.6%39.1%
2008, E, WordValue >= -142.2%42.7%46.4%

What I found is that lower WordValues actually repayed at a higher rate than higher WordValues--exactly the opposite of what I was expecting. This means that some of the low performing words in loans before 2008 performed better than average in 2008 loans.

Since my original conjecture is that the word "need" performs less well than average I tested that on this same set of loans and found the following:

DescriptionPaidRecoveredNever Recovered
2008, D, All49.8%50.7%34.7%
2008, D, Title or Description contain "need"49.7%50.7%36.2%
2008, D, Title or Description do not contain "need"49.9%50.7%33.8%
2008, E, Title or Description contain "need"43.5%44.6%39.3%
2008, E, Title or Description do not contain "need"44.6%45.4%41.6%
2009, D, All27.9%27.9%13.4%
2009, D, need in title or desc25.5%25.5%14.7%

We get mixed messages here, too. In 2008 D loans with "need" were about 2.5% more likely to never recover (meaning they were confirmed to Default or Charge Off) but roughly equally as likely to have ended with a "Paid" status. 2008 E loans with "need" are, to date, less likely to have finished their loan with a "Paid" status but 5.5% less likely to never recover. 2009 D loans are less likely to have ended and Paid and more likely to never recover.

Now obviously not all 2008 and 2009 3-year loans have reached the end of their term. We'll be able to draw better conclusions in the coming months, but it's entirely possible that there is no correlation between "need" and loans which aren't repayed.

In future posts I'll whittle down my list of words that fail and see if I can find a set of words that consistently has results which are worse than the average.



About the WordValue number:
I created the WordValue by taking the difference between the Paid percentage of loans containing each word and the average repayment rate for loans before 2008. I only used words that were more or less than .5% of the average.

The WordValue number is the sum of each of those differences from the average taken only once per word.

Wednesday, August 17, 2011

Machine Lending

For those of you not already in the know, Stanford is offering a few free AI classes online during the fall semester. Introduction to Artificial Intelligence and Machine Learning seem like they'd both offer interesting advice on creating a program which could pick loans with a better chance of repayment than I would pick by hand.

I'm looking forward to the start of the classes. It isn't as cool as designing a self driving car but it's a start.

Monday, August 15, 2011

What's Coming

With the belief that the way people write their requests for loans reflects their attitude towards lending and, therefore, their probability of repayment, I set out on a journey to find words which are associated with failed loans.

So I looked at the word "need" in a few different ways. I saw that there is variation on Prosper across the years and across the credit grades, and I've seen that something similar is happening on Lending Club.

I also looked at words that are associated with failed loans and words that are associated with loans that get paid off.

In the next few weeks, I'll start testing the words that have failed before and see if they fail on newer loans with the idea of building a list of words that, if used by a borrower, indicate that a loan is more likely to fail. I'll show how my first attempt failed -- words associated with failure in Prosper loans before 2008 weren't all associated with failure in 2008 loans -- and I'll try different sets of words to see if I can find some consistent pattern.

Sunday, August 7, 2011

Needs Series: Comparing to Lending Club

Of course all of this needs data does us absolutely no good if it isn't generalizable beyond the loans that it came from. Since the initial data was taken from Prosper, it seemed that Lending Club loans would be make a good comparison and continue to tell us if we're finding something relevant or just random noise.

Data Set: All Lending Club Loans made in 2007 and 2008

2007-2008 LoansTotal LoansPercent Charged Off or Defaulted
All Loans299621.2%
"Need" in title or description81426.8%
"Need" not in title nor description218219.2%
"Payday" in title or description757.1%
"Payday" not in title nor description298921.1%

So there you have it, the word "Need" appears to correlate more often with a failure to repay a loan in Lending Club as well. (I included "Payday" data just for fun -- with only 7 loans the data isn't likely to be relevant, but it does fall in line with what we'd expect.)

Since so many of the 2009 loans won't be paid off until 2012, I included the >30 days late category with the already Charged Off and Defaulted loans and found the following stats:

2009 LoansTotal LoansPercent Charged Off, Defaulted or >30 days late
All Loans528110.7%
"Need" in title or description126313.6%
"Need" not in title nor description40189.8%
"Payday" in title or description683.3%

The trend continues...


All Articles in the Needs Series
An Introduction
Initial Findings
Correlation Matrix
Comparing to Lending Club