Market VaR and Credit VaR Measure Different Portfolio Risks
Summary
The document distinguishes market value at risk from credit value at risk. Market VaR estimates a portfolio loss threshold over a chosen horizon and confidence level using market risk factors such as rates, foreign exchange, spreads, and equity prices. Credit VaR instead focuses on changes in debt value caused by default or worsening creditworthiness, with portfolio correlations playing an important role.
It also notes differences in typical horizons and distribution shape: credit risk is often assessed over longer periods and can have more skewed returns. The discussion distinguishes both measures from conditional VaR, or expected shortfall, which averages losses beyond a specified threshold and is described as coherent. The explanations are conceptual rather than a complete implementation guide; results depend on the selected horizon, confidence level, model, and portfolio assumptions.
Key ideas
- Market VaR estimates a loss threshold over a specified horizon and confidence level from market risk factors.
- Credit VaR measures losses associated with default and deterioration in counterparties’ credit quality.
- Credit VaR often concerns longer horizons and skewed credit return distributions.
- Credit VaR and conditional VaR are distinct concepts, despite overlapping abbreviations.
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# Difference between VaR and credit VaR?
# Difference between VaR and credit VaR?
Quick question: is there a difference between credit VaR and VaR or are they the same thing?
## Answer by Jacob M. Morley (score 2)
https://quant.stackexchange.com/a/10674
They are different metrics.
As I understand it:
- Market risk VaR is a not a coherent risk measure, because it is not subadditive.
- Market returns are generally considered on a shorter time horizon relative to credit returns, which has implications for expected return drift (namely, credit return drift is likely more substantial, as credit is longer dated).
- Credit return distributions are also considerably more skewed.
Credit VaR effectively subtracts the expected portfolio value from a confidence cutoff value (often something like from 95 to 99.9 percentile). I.e. it is the value at the confidence cutoff less then expected value of the tail region for which it is the right bound. Malz has a bit more on credit risk VaR in Chapter 6.9.1 a
Somewhat Related (and confusing, since a few resources I have seen have referred to CVaR as either credit and conditional VaR):
Conditional VaR (or expected shortfall) is $\frac{\int_{-\infty}^c f(x) x \, \mathrm{d}x}{\mathbb{P}\{x \le c\}}$
where $c$ denotes the value threshold that corresponds to the percentile of interest. It is coherent.
## Answer by SolitonK (score 2)
https://quant.stackexchange.com/a/33671
I would like to bring this topic back to life as I believe it calls for some further explanation and disambiguation of definitions.
VaR - Value at Risk - is a statistical technique which, given some parameters (horizon, confidence interval, look-back period) and estimation methodology, attempts to forecast the worst possible loss of my portfolio (with a given confidence) at any given horizon. So, for example having a portfolio on which I calculate a 99% 1-day VaR and found it to be 100k, the results could be interpreted as following, at any given one day, with 99% certainty, my portfolio is not expected to loose more than 100k.
Typically, how this is done is, by decomposing all assets of the portfolio into relevant risk factors (factors relevant for its valuation) and simulating their behavior, re-value the entire portfolio. Such factors can be swap curves, FX rates, credit spreads, equity prices, equity indices, implied volatily etc. This approach as it is evident, concerns market risk factors and how they on a day-to-day affect the performance of the portfolio.
Credit VaR - this statistical technique (various implementations and methodologies) provides a measure of the portfolio's risk given changes in the value of debt caused by counterparty default or deterioration of that counterparty's credit worthiness. Furthermore, intra-portfolio asset correlation is an important aspect here (a lot of discussion can be made around this topic and various methodologies have been developed). As it is evident, this type of technique most closely concerns debt portfolio with longer horizons.Shown in full with attribution under the source's licence. Licence: CC BY-SA 4.0 (Stack Exchange)
This summary was written by Stratmill's research agent from the original; it is not a copy of the source.