# All Questions

12,638 questions
57 views

### Best practice approach for computing beta

I was wondering how one should choose parameters such as "frequency" of returns (daily, monthly etc.), "time frame" (1 or 3 or 5 years of historical data etc), benchmark (same of the portfolio or the ...
70 views

### What are some scenarios where trading a risk reversal makes sense?

I understand that risk reversal is a bet on the skew of the implied volatility curve. But when would one have a view on the skew of the curve? I understand that one can have a view on the underlying. (...
29 views

### Relationship between Tracking Error and Beta to benchmark

Analyzing an indexed portfolio, can we say there is any relationship between ex-ante TE and Beta to benchmark? Tracking error is the volatility of the difference in returns between the portfolio and ...
47 views

### API returning company tickers found in provided news article

I'm looking for a REST API (paid or free) that accepts a string containing a news article (example below) as payload and returns an array of company tickers (eg TSLA for Tesla) mentioned in the ...
38 views

### Brownian motion from price-series, what is the time step?

If I assume a given empirical price-series is a brownian motion, I can estimate the drift and standard deviation as long as I know what the time step was when the process was 'generated'. But since ...
32 views

### Approximation of portfolio VaR (after mapping) when Delta and Gamma both equal zero

As titled, I am having trouble estimating the VaR of a portfolio mapped as a function of a single risk factor $S$, in the form : $$V(S) = S^3 - 30S^2 + 300S + 150$$ with current value $S = 10$. $S$...
24 views

### Why no median-CVaR optimization for portfolios?

Question Since CVaR is a concept that can be applied to all probability distribution, even if they do not follow normal distribution, I thought CVaR should be more concerned with median, not the ...
73 views

### How to add Risks-Not-In-VaR (RNIV) to VaR under Basel III

I am trying to generate/prove the magnitude of the over-conservativeness of the regulatory VaR (internal models) under Basel III against what a more accurate VaR would be. However, I can't seem to ...
69 views

### Why can we assume that asset return rates are normally (or lognormally) distributed?

In many theories of financial mathematics it is assumed that asset return rates are normally distributed (e.g. VaR models) or lognormally distributed (e.g. Black-Scholes model). In practice, asset ...
41 views

### Constructing Portfolio Beta

Suppose I have a portfolio with securities with different history. Say some securities have 15-20 years of history and some are like Uber or Lyft, which has limited history. There are assets with 1/2/...