- September 25th, 2018, 6:02 pm
- Forum: Book And Research Paper Forum
- Topic: Introducing XGBM -- a new stochastic volatility model with some nice properties
- Replies:
**9** - Views:
**5017**

Congrats Alan. It looks like you put a lot of work into this. I like that the paper appears to be self-contained, no need for heat kernels on hyperbolic manifolds, geodesic distance and all that. Great job. Now a quick question. You are saying it takes roughly ten times longer to price an option i...

- August 25th, 2015, 10:47 am
- Forum: Technical Forum
- Topic: Avoid negative interest rates in Hull White model
- Replies:
**12** - Views:
**35139**

Can you be more precise about this? Is the volatility a step function of time, or of the short rate, or something else?

- July 31st, 2015, 7:52 pm
- Forum: Brainteaser Forum
- Topic: Making Money on Zero Drift LogNormal Random Walks
- Replies:
**9** - Views:
**10382**

<t>Another way of answering your question is that no, you can't make money. The stated assumptions are that the stocks themselves are driftless, so their SDE would look like dS = sigma S dW, not that their logs are driftless. If the stocks themselves are martingales, there is no way to systematicall...

- August 21st, 2014, 7:30 pm
- Forum: Brainteaser Forum
- Topic: Coint toss game
- Replies:
**16** - Views:
**11152**

If A gets tails, basically the game starts afresh, only that A is the second player now. The probability that the second player wins is P(B). So P(A|T) = P(B).

- August 4th, 2014, 1:12 pm
- Forum: Programming and Software Forum
- Topic: Tridiagonal solver parallel algorithm
- Replies:
**19** - Views:
**5098**

- December 20th, 2013, 7:13 pm
- Forum: Numerical Methods Forum
- Topic: Pricing Basket Options using Black-Scholes by BDF2 after using PCA for dimension reduction
- Replies:
**17** - Views:
**7815**

<t>Hi radhikanangia, I didn't look at your code, and I don't think I will have time to. I have to say I like a lot the paper that you are trying to replicate.One thing: I don't think you need any finite differences. For the setup in the paper, quadrature is enough. I believe it will be much faster a...

- May 13th, 2012, 12:12 am
- Forum: Brainteaser Forum
- Topic: I read this forum too
- Replies:
**9** - Views:
**37525**

Looks like this entry created quite some stir on Hacker News. Lots of insightful comments.

- March 4th, 2012, 3:19 pm
- Forum: Brainteaser Forum
- Topic: exp(5) = [$]e^5[$]
- Replies:
**544** - Views:
**118282**

<t>Here's a cute way to calculate exp(5). Use Stirling's formula: 5! ~ 5^5 * exp(-5) * sqrt(2*pi * 5)We get exp(5) ~ 625*sqrt(10 pi) / 24Now, one can argue that: 1. this calculation is hard to do by hand, and 2. it's a rough approximation anyway. 1. It so happens that this calculation is easy for so...

- June 24th, 2011, 12:24 am
- Forum: Book And Research Paper Forum
- Topic: Mortgage bible
- Replies:
**10** - Views:
**23250**

It's probably less than what you are looking for, but it's a good start. As for Hull's book, I'm not sure who holds it in such high esteem. If you want a real good benchmark, that's Andersen and Piterbarg.

- June 23rd, 2011, 1:10 am
- Forum: Numerical Methods Forum
- Topic: CLO default correlation
- Replies:
**2** - Views:
**24155**

<t>You should read about the "gaussian copula" credit model. It's quite famous, and it landed a place of honor on Paul's "Name and shame" list (some people think the gaussian copula caused the crisis). Observing a Bernoulli variable X (1 with p, 0 with 1-p) is the same as observing a normal variable...

- March 29th, 2011, 4:32 pm
- Forum: Careers Forum
- Topic: A tricky situation
- Replies:
**16** - Views:
**21506**

<t>The labor market may not be perfect, but it's not completely irrational either. It's supply and demand. If she gets any other competing offers, then her current pay is irrelevant; her MTM will be decided through an auction. If she doesn't, then the potential future employer has to compete only wi...

- March 16th, 2011, 4:17 pm
- Forum: Student Forum
- Topic: 3s versus 6s swap
- Replies:
**4** - Views:
**20629**

<t>Saharasjj,Not sure I understand your question correctly, but I think you mean that one party pays 3y CMS rate (plus a spread) and the other pays 6y CMS rate (where CMS = constant maturity swap).If that is the case, you need to look into CMS pricing. It's possible to statically hedge a CMS with sw...

- March 14th, 2011, 3:21 pm
- Forum: Careers Forum
- Topic: Resign
- Replies:
**17** - Views:
**26876**

That's a nice war story Quantmeh. Thanks for sharing.

- March 9th, 2011, 8:14 pm
- Forum: Numerical Methods Forum
- Topic: Seed value for Random Number Generator
- Replies:
**11** - Views:
**23050**

Good point. It makes sense to run the pricer several times with different seeds to see what the stdev of the error is. Also, it would be probably a good idea to do the same exercise for the hedges as well.

- March 9th, 2011, 2:36 pm
- Forum: Numerical Methods Forum
- Topic: Seed value for Random Number Generator
- Replies:
**11** - Views:
**23050**

<t>Well, how do you decide what part of the hedge is noise and what is the "true" hedge? People think that if your MC error is below, let's say 0.1bps (or some other arbitrary number), then you are close enough to the real price; the problem is that there is no real price. There is always model risk...

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