The calculated approximation of a result which is usable even if input data may be incomplete or uncertain.

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4
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1answer
98 views

How are Quandl monthly S&P500 earnings estimates derived?

Can someone explain how the monthly earnings estimates are derived for S&P500? Quandl sources multpl.com, who state: ...
6
votes
0answers
166 views

Estimating Parameters - Vasicek

The Vasicek model for the short rate $r_t$ is given by the SDE $$ dr_t = \alpha(\beta - r_t)dt + \sigma dW_t, $$ where $W_t$ is a Brownian motion under the physical measure. I'd like to compute bond ...
6
votes
0answers
69 views

What kind of errors arise when I fit ARMA(1,1) to data generated from ARMA(1,1)-GARCH(1,1) process?

As far as I know estimates of parameters of ARMA(1,1) are asymptotically optimal when fitted to data from ARMA(1,1)-GARCH(1,1) process, and only their variance increase, so when we assume large ...
4
votes
0answers
218 views

Estimation of ranks of log-returns via copula

I have successfully chosen and estimate a copula for the ranks of the log-returns of my actions. My question is, since I have worked with the ranks instead of directly the log-returns (in order to be ...
3
votes
0answers
103 views

Derivation of variance of Zhou (1996) volatility estimator

Does anyone know how to derive the Variance of Bin Zhou's volatility estimator (Theorem 1) in 'High-Frequency Data and Volatility in Foreign-Exchange Rates' (1996) Zhou 1996 Any help would be ...
3
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0answers
173 views

Should I use Resampling or Expectation Maximization to compute a robust covariance matrix?

I have several assets, each with different return histories. Some of the assets have 75 days of return history, others have 40 or so days. In calculating a robust covariance matrix, should I be using ...
2
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0answers
38 views

How to calculate the estimation error of portfolio variance using propagation results?

I am trying to find a conservative approximation for the propagated estimation error of a investment portfolio's variance (comprising two assets), given we know the estimation error for the variance ...
1
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0answers
18 views

Relationship between in-sample and out-sample periods length

I have two general questions regarding "in-sample fitting vs. out-of-sample backtesting" kind of analyses. Is there any relationship between the length of the data collected for in-sample fitting ($a$)...
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0answers
66 views

How to fit exogenous + GARCH Model In Python?

I am studying a textbook of statistics / econometrics, using Python for my computational needs. I have encountered GARCH models and my understanding is that this is a commonly used model. In an ...
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0answers
138 views

Skewed Generalized Error Distribution's (SGED) pdf

I want to use the SGED distribution of Theodossiou for GARCH estimation, however, I am struggling to understand which is the correct pdf function of the distribution. Let me just say that the ...
1
vote
0answers
55 views

What are the estimation methods for SV models?

I want to know about some methods like Methods-of-Moments, Quasi-Maximum Likelihood method, Baysian methods using Markov Chain Monte Carlo methods. Is there any reference to have an idea of these ...
1
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0answers
101 views

Derivation of a ML estimator

I have the following likelihood function: I'm given this information about the $\Omega$ matrix ($\boldsymbol{1}$ is a $T \times 1$ vector of ones): I would like to be able to show that the ...
0
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0answers
13 views

Do smaller horizons better estimate volatility for longer horizons than the longer horizons?

Suppose you want an estimate of the 20 day return variance. You could grab historical lagging 20 day windows to build an estimate, or you could build 10 day lagging windows (twice as many data points) ...
0
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0answers
20 views

Modeling the distrubution of future swap rates

I'm interested in better understanding the unwind cost/value of a swap at various points in the future. Suppose that we have entered a 7Y swap (paying fixed) and want to understand the unwind cost/...
0
votes
0answers
27 views

is mean and variance sufficient to determine the following question?

consider this question: I want to buy AAPL, and I could buy it from 3 brokers. I have their historical quote. Is there any statistic other than mean and variance I could use to determine if one broker ...
0
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0answers
19 views

Asset weights in asset allocation

I am trying to solve an asset allocation problem by approximating the expected utility of a portfolio. I am using the following formula: $E_t [U(1 + w_t' r_{t+1} + w_{ft} r_{f, t + 1})] = m_{1,t+1} - ...
0
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0answers
90 views

Forecasting conditional variance using fGARCH

I am forecasting the conditional standard deviation using ARMA(1,0)-GJRGARCH(1,1) in R using the fGarch package. Here is a sample code: ...
0
votes
0answers
193 views

Forecasting conditional mean in ARMA-GARCH model (R/Matlab)

I am trying to forecast the conditional mean from a ARMA(1,0)-GARCH(1,1) model. The mean equation in my model is: $x_t = \mu + \delta x_{t-1} + h_t \epsilon_t$ where x is the variable (a return ...
0
votes
0answers
90 views

Skewed Generalized Error Distribution in GARCH modelling

I am trying to estimate GARCH models with the use of Theodossiou's (2000) Skewed Generalized Error Distribution. I am modifying matlab's ARMAX-GARCH-K toolbox to calculate this model. I am calculating ...
0
votes
0answers
130 views

Maximum Likelihood Estimation Heston Model using Matlab

My question is based on the MLE of the Heston model discussed in this paper URL: http://www.princeton.edu/~yacine/stochvol.pdf with Matlab code: http://www.princeton.edu/~yacine/closedformmle.htm ...