Questions tagged [risk-models]
The risk-models tag has no usage guidance.
147
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Marginal Risk Contribution under Factor structure
Given the factor structure below with K factors, the return for N assets is given by (under matrix notation):
$R =\alpha + \beta F + \epsilon$
where $F$ is matrix of K factor returns and $\beta$ is ...
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35
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How to combine DV01s from multiples maturities into fixed ones?
Suppose I have multiples maturities on my book of IRS trades , each one maturing in 15, 35 , 58, 65, 70, 74, 95 (...) days.
How do I decompose (or combine) the DV01 for each flow/maturity into fixed ...
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55
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How to test a risk model?
I'm reading the Barra risk model handbook (2004) available online and trying to understand the methodology. I've read a few materials on portfolio theory, so I can get at least the theoretical ideas ...
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76
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Techniques for proxying time series / stock prices
What are some good techniques for proxying time series?
My purpose is for risk management / modelling and I would like proxy to missing series.
Given that I also have to account for volatility, ...
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23
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MultiFactor Risk Model Ex Ante StDev vs. StDev of Monte Carlo PnL Distribution
In the context of applying a multifactor risk model to a portfolio of linear and nonlinear equity securities, why would there be differences between the calculated ex ante portfolio stDev and the ...
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94
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Introductory Books to Network Theory
Can anyone please suggest a good introductory book to Network Theory which is the area of mathematics that is widely used for systemic risk and contagion modeling in finance. If the book contains some ...
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39
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Core deposits forecasting in stress testing
I’m designing a stress test at a commercial bank. What are the advantages/disadvantages of forecasting core NMD deposits vs. total deposit balances?
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84
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Calculation of Total Credit Risk Capital % but seeing lower capital percentage for higher risk band. Is there any correction required?
I am trying to calculate the Total Credit Risk capital % for my learning purpose as given below. Assuming adding 1 single loan with different pds.
i have noticed one point in the table and have two ...
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135
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Why does Hierarchical Risk Parity ignore the clusters generated?
I am currently working through the Hierarchical Risk Parity algorithm (Lopez de Prado (2016) link ) and trying to understand each of the steps.
I have completed the step of creating the clusters, and ...
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29
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what is the right time period for estimating factor loadings in multi factor models?
Is there a generally recommended time frame (12 months, 24 months, 60 months) for estimating the factor loadings (betas) in a multi-factor model such as Fama French or Carhart or equivalent?
4
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are there any good papers on sector-specific versions of factor models?
Does anyone know of any good papers that build sector-specific (utilities, financials, energy, etc.) versions of factor models like the Fama French 3-factor or Carhart 4-factor models?
For example, ...
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2
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141
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Filtered Historical Simulation VaR for swaps
I am trying to understand how to calculate FHS VaR for a portofolio of vanilla swaps. I think I understand the main ideas behind FHS VaR and how to implement it for other assets such as equities. I ...
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63
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Infill lower frequency data: Brownian Bridge
Given monthly returns data, I would like to infill those to get daily returns. Roughly estimates imply that annual volatility is about 1.5x of SPY. One option that came up in my initial research was ...
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0
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90
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Practical implications of Andy Lo paper on Sharpe ratio using quarterly returns?
I am hoping to determine the practical implications of the Andy Lo paper criticizing the use of a scaling factor in converting periodic Sharpe ratio to annualized Sharpe ratio. I am particularly ...
4
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0
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86
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Ruin theory with infinite-mean Pareto-distributed claims: how to characterize the ruin time and the reserve prior to ruin
Consider the Cramér–Lundberg model
$$\hspace{8em}R(t)=u+c\,t-\sum_{j=1}^{N(t)}V_{j}\,,\hspace{8em}(1)$$
where $c$ and $u$ are positive constants, $N(t)$ is a Poisson process with a rate $\lambda$ (in ...
4
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0
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107
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Market Risk FRTB - How to demonstrate that the linear transformation of the alternative definition of Vega reflects the actual vega risk?
I have a question regarding the use of alternative vega sensitivities (bank system sensitivities) in the context of the Vega Risk Charge of the SBM.
The article 325t.6 of the CRR allows banks to ...
14
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1
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886
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Quantifying climate change risk
I am looking for resources on applicable and practical solutions for estimation and quantifying climate change risk from asset owners perspective (for example, a portfolio of equity, fixed income, and ...
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146
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What is the market share of MSCI Barra Equity Model?
My understanding is that MSCI/Barra's model has a very large market share in funds and banks, but I cannot find out how large is the exact market share.
Is there any data on this, or can someone ...
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48
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Variables for retail lending of bank
Typically to estimate the credit-worthiness of customers in retain bank lending, banks generally consider many demographic and socio-economic variables most importantly -
Age, number of dependents, ...
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1
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88
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Standard market risk platform Value-at-Risk (VaR)
if possible, could you share publicly available methodological guides/pamphlets or post links to specialised websites which give sufficient detail of the basic assumptions, algorithms and possible ...
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0
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103
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Calculation of Expected Shortfall using IMA Approach ( FRTB)
I am trying to calculate the Expected shortfall of a FX portfolio through IMA Approach of FRTB in excel . I have used several combinations in excel to get the liquidity horizons and then calculate the ...
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94
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What happens if my risk factor caught by statistical risk model using PCA turns out to be totally different from other PM's risk factor? [closed]
In order to explain systematic risk we use risk factors and I've learned that since they try to explain 'systematic' risk, risk factors are relatively well-known.
However, what happens if the risk ...
2
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0
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137
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Is implied volatility really all that usefull?
I take implied volatility as the positive floating point number which lets the BS formula match an observed option price (assuming we have some useful interest rate, some underlying, etc).
How useful ...
2
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0
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85
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Arrow Debreu Price vs Green's function
How is the Arrow Debreu Price related to Green's function at an intuitive level and how is this used in practice?
Note Added 2021/02/01
I came across this in the Black Derman Toy model paper by Boyle, ...
2
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1
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123
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Downside deviation (semivariance) in m.v. portfolio optimization
Currently I am considering the downside deviation or semivariance in a m.v. optimization framework.
For this specific measure of risk I have found in papers different formulae. The majority of them ...
2
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1
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314
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Mean Absolute Deviation in m.v. portfolio optimization
I just read some articles about $MAD$ as a measure of risk in finance.
Is the following formulation a correct way to implement a $MAD$ portfolio optimization model which minimizes risk without ...
2
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0
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204
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Implied Gamma VS Implied Volatility
Reading this paper, I'm struggling to understand what the author is saying with paragraphs below (see pages 39-42):
We define Implied Gamma ($\Gamma_{\operatorname{implied}}$) as the value of the ...
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1
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146
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Capital Allocation, VaR, Expected Shortfall
Are there any serious drawbacks / weaknesses in the Euler allocation method, when used to allocate VaR capital (and potentially Expected Shortfall) to risk factors in a portfolio? I notice that ...
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1
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135
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Model Validation Aggregation Documentation (Binomial, Hosmer-Lemeshow, Tolerance) - Credit Risk et cetera
I came across some document that says for a PD (Probability of Default) model in order to assess its accuracy you need to first look at the Binomial Test, then the Hosmer-Lemeshow Chi-square test, ...
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1
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66
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I’m trying to construct a binomial model that uses 2 risky model - number of steps varied
So with this question I am unsure how to even do a binomial model with 2 risky assets never mind having n-steps. All the examples I’ve found are either not containing any risky assets or only have one....
2
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1
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406
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Code (Python or R) references for operational risk models (AMA/COM)
I have to build an operational risk model and to be compliant with Basell II and III regulations I thought of using AMA (Advanced measurement approach) or COM (change of measurement).
We have no ...
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2
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1k
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Do the weights of the exponentially weighted moving average (EWMA) have to sum to 1?
I am currently trying to calculate a volatility by using the EWMA model because it is said to yield better results than just using an equal weighted calculation approach. However I am a bit confused ...
3
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0
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62
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ESG risk factors
In the context of EU action on sustainable finance, the European Commission has initiated a series of regulations in order to achieve the goals of Paris Agreement on sustainability.
One of those ...
0
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1
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82
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Ratios or combinations of risk measures
In finance, alternative risk measures such as value-at-risk (VaR) and GARCH are introduced as replacements to standard deviation volatility.
Is there any application or value where several risk ...
2
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1
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637
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Open source projects to gain demonstrable experience in implementing modeling in C++
I have a mathematics background with a PhD in mathematics (not related to stochastic processors or financial mathematics) and have been in derivatives valuation for around 6 years. When applying for ...
3
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1
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168
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Why didn't stock markets drop in response to COVID-19 earlier, way before Feb 21 2020?
The S&P500 started to drop only on Feb 20 2020, and the Nikkei 225 and the FTSE 100 on Feb 21 2020. Yet as early as Jan 120, COVID-19 was reported in Hong Kong, South Korea, and Japan. Their ...
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1
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114
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How to model/price the risk of Covid-19 and other pandemics
How would you model and price the risk of Covid-19 pandemic? These large cost low probability events with very little history seems to pose a particular challenge when quantitatively modeling and ...
2
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2
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161
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Quantitative risk management for energy markets
I'm currently preparing an exam about energy markets. The knowledge of notions of quantitative risk management accounts for the 50% of the total exam. During my university education, though, I didn't ...
2
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0
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64
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Where could I find code to compute Potential Future Exposure
Ideally code in SAS, R, Python or Matlab for calculations involving counterparties holding positions in energy markets on multiple price curves, with a Monte-Carlo methodology or a simpified ...
2
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3
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214
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PD and LGD for ECL calculations needs to be time dependent?
I'm studying the implementation of an expected credit loss (ECL) model. I have encountered a complication. Do I need to calculate a probability of default (PD) and loss given default (LGD) with a time ...
0
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1
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141
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Demonstration of the Schweinler-Wigner Orthogonalization procedure
Can anyone give me a practical demonstration of the Schweinler-Wigner Orthogonalization procedure? The steps of performing it or possibly a code snippet.
The Schweinler-Wigner Orthogonalization ...
2
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1
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3k
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Absolute and Relative Value at Risk
Is it correct to calculate the VaR as 99% max between loss and profit. E.g. if 99% VaR on the loss side of the distribution is -100, and on the positive side of the distribution there is a value ...
3
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2
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368
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Stop-Loss strategies
Does anyone know some bibliography about the problems or limitations of using Stop-Loss strategies in a portfolio?
Let me explain better: for example you can have a portfolio of 30 stocks from ...
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0
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105
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How to correctly simulate volatility shocks?
I am working on the comparison of different volatility timing/target strategies on portfolios starting from different conditions (data, asset classes, calculation of realized volatility, different ...
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1
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113
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Backtesting a stock scoring model
I'm working on a simple stock scoring model consisiting of 3 factors:
1.market cap
2.liquidity of the stock
3.the value at risk
we defined 3 intervals for each factor and we assigned the ...
3
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1
answer
301
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Portfolio Systematic Risk, Breaking it down into factor % contributions
I have a portfolio (p) of N equities, with let's say weights vector (m) at the start of the calculation period. Each equity has its own set of factors (like corresponding country, industry index, etc.)...
2
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0
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58
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Conceptual help - Machine Learning on finance data set [closed]
I am working on Anomaly detection model problem for a finance data set - set of gift card activation transactions. My team member suggested an idea that " First train the model with normal instances ...
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1
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466
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Barra model: why standardize the fundamental risk factors?
The two main types of risk factors included in the famous Barra model are called the "fundamental factors", and "industry factors," and the thing that I do not understand is why are only the former ...
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53
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How to Risk and Return using Carhart 4 factor model
I have to calculate firm risk and return for a group of firms. I have firm CUSIPs. I also have access to CRSP data from WRDS. Can someone explain to me how I can use CRSP and data from Ken French’s ...
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Dominating credit risk modeling approaches for capital calculation in banks
In Basel/CRR (capital requirement regulation) there are various approaches for the estimation of capital requirements.
For corporate exposures there is the Foundations IRB approach (F-IRBA, own ...