A measure of the variation in price over time. Also a measure of the risk of a financial instrument.

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Portfolio volatility

Problem True or fale? The stock of a firm has an expected return of 10%, and a volatility of 10%. The weight of the stock in a portfolio is 5%, and the correlation of the stock’s return with the ...
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5answers
545 views

Construction of “vol of vol”

How do you construct something that lets you buy "vol of vol"? not necessarily for VIX, but any particular stock or index.
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6answers
13k views

How to calculate historical intraday volatility?

Sorry for what must be a beginner question, but when I went to write code I realized I didn't understand exactly how historical volatility, or statistical volatility, is defined. Wikipedia tells me ...
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0answers
81 views

High frequency price forecast model ARMA GARCH or another?

Can you reccomend model for high frequency data (1 second and less) (returns and volatility forecasting)? Most papers use ARMA, GARCH etc in 1 minute and lower time frame. PROBLEM ARMA does not know ...
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2answers
111 views

A good way to calculate the realised daily volatility

Currently, I am confused about the calculation of realised daily volatility. Assume I have daily returns, for example, FTSE, then I need to estimate the daily realised volatility. I read some ...
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1answer
70 views

Volume or Volatility?

I've recently been given a project which came with some documentation. In this documentation is a bullet point that reads: Liquidity Risk in Equity, Credit and Vol I'm unsure as to whether vol is ...
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62 views

Cointegration and variance of time series

Given that $X_t , Y_t$ are two cointegrated random processes, what can we say about the relationship between variance of the two increments $var(X_{t+h}-X_t)$ , $var(Y_{t+h}-Y_t)$ for a given ...
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2answers
75 views

Short Volatility [closed]

Being net short options is an obvious case of being short volatility. But what other investments are "functionally" short volatility? Is long equities long or short volatility? Is short Apple long or ...
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3answers
126 views

Direct use of implied volatility

I am not sure to understand exactly the direct use of implied volatility. Let's take an example: if an instrument has a daily volatility of $\sigma$, there is a 68% probability that its value will be ...
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1k views

Correctly applying GARCH in Python

Problem: Correct usage of GARCH(1,1) Aim of research: Forecasting volatility/variance. Tools used: Python Instrument: SPX (specifically adjusted close prices) Reference material: On Estimation of ...
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1answer
57 views

Solving a Non-Linear PDE using a Finite Difference Scheme

I have the following non-linear PDE and I have no idea how to go about solving it using a finite difference scheme in Python. Can someone get me started and/or point me to an algorithm for doing this? ...
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0answers
59 views

variance ratio for pair-trading

I am using the variance ratio test to check whether my sequence is mean reverting in that test there is a parameter n, How in general I choose this n? or what is the meaning of this parameter? ...
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2answers
683 views

Volatility of a rolling window strategy

What methods can be applied to determine the volatility of strategy using a rolling window? Using normal standard deviation would bias the results as the returns will be highly correlated. Although, ...
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466 views

Do intraday volume and volatility share the same properties?

volatility clustering and mean reversion are very well known properties that one could use when trading. Traders, especially in options world, do take realized vol into account (e.g. by forecasting it ...
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1answer
105 views

Question about historical volatility ranking

I have seen this strategy example, which uses garch in a regime switching context: https://systematicinvestor.wordpress.com/2012/01/06/trading-using-garch-volatility-forecast/ The author classifies ...
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2answers
129 views

Time-independent local volatility

Suppose somebody provides us with a surface of European call prices $C(\tau,K)$ where $\tau$ stands for time-to-maturity and $K$ for the strike. By Dupire's results, there is a unique local volatility ...
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0answers
46 views

How to calibrate volatility surface for Interest Rate Cap&Floor pricing

I'm using Black model to do interest rate Cap & Floor pricing. The volatility is determined by using the bootstrapping methodology. However, afterwards, how should I do the calibration, or ...
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2answers
92 views

I have portfolio volatility for individual years, can I use them to compute portfolio volatiltiy for subperiods?

Thanks for opening this question. I have constructed some rules for a portfolio with annual rebalancing and am backtesting it for the period 1990-2014. I want to compare the risk-adjusted return to ...
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2answers
237 views

Is there a way to adjust R PerformanceAnalytics function VaR with EWMA or GARCH method?

Is there a way to upgrade R PerformanceAnalytics function VaR with more risk sensitive approaches like EWMA or GARCH? Or is there another R package which can handle the issue?
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1answer
117 views

Volatility updating rule using r

I'm trying to program a volatility updating rule using iteration. I start with the well know Heston-Nandi model where the returns dynamics are : with is iid standard normal randome variable, where ...
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1answer
144 views

On an application of Ito's lemma

Assume that instantaneous returns are generated by the continuous time martingale: $$dp_t = \sigma_t dW_t$$ where $W_t$ denotes a standard Weiner process and One day returns are denoted by $r_{t+1} ...
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0answers
41 views

Hedge volatility decreases

My particular options positions are typically a long delta, and long vega. Decreases in implied volatility, or specifically the VIX, can drastically alter the profitability of my position. Is there a ...
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2answers
70 views

Garch for covariance matrix?

I have seen plenty of literature about GARCH on estimation volatility. how about covariance? There are plenty of risk models depending on the covariance matrix. I guess we can assume the correlation ...
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1answer
262 views

using garch to forecast volatility but getting low persistence model

I am using a GARCH(1, 1) model to try model volatility for a certain stock. I have a GARCH function in matlab that returns the three parameters, omega, alpha & beta. I then use this parameters ...
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1answer
58 views

Variance Swap volatility

In an article, it is mentioned that a parameter is "the variance swap volatility at time t". I know what a variance swap is but I don't know what they could mean by "variance swap volatility". ...
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66 views

DCC GARCH - Specificating of ARCH and GARCH parameter Matrices STATA

The command in STATA to calculate the DCC model of two variables is: mgarch dcc ( x1 x2=, noconstant) , arch(1) garch(1) distribution(t) $$ \begin{bmatrix} ...
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2answers
144 views

How to write a home task report which is part of the interview process for a quant position in a trading firm

I recently appeared in an interview for a quant research post in a trading company. As part of the interview, I was given a home-task to solve in a week. The inerviewer gave me a dataset consisting of ...
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0answers
44 views

SRRI calculation for absolute return funds

I am trying to understand the formula for calculating SRRI for absolute return funds described in ESMA's guideline CESR/10-673, and Richard's answer has been of great help (What does this formula (to ...
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1answer
111 views

What is an appropriate algorithm to use for tax loss harvesting?

I've been reading into how Betterment and Wealthfront have architected their tax loss harvesting algorithms, but they stop short of providing any real examples. Essentially, they both reduce to: ...
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0answers
36 views

Correction factors for volatilities of smoothed returns

In An Introduction to High Frequency Finance (http://www.amazon.ca/Introduction-High-Frequency-Finance-Ramazan-Gen%C3%A7ay/dp/0122796713), the authors (on page 253) build a tick-frequency volatility ...
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0answers
37 views

Reputational Harm

How would you measure the reputational harm incurred on an individual by an organization. How is Market Pricing in the expected payout resulting from the law suit by an individual ? The news breaks ...
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7answers
25k views

What is the difference between volatility and variance?

How do volatility and variance differ in finance and what do both imply about the movement of an underlying?
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2answers
65 views

I have portfolio volatility for year 1 and for year 2. What is portfolio volatility for year 1 and 2 combined?

Thanks for looking into this question. Portfolio volatility in year 1 = 15%. Portfolio volatility in year 2 = 20%. What is the portfolio volatility over the timespan year 1 and 2 combined? Is it ...
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0answers
105 views

How to hedge a long stock with the corresponding volatility ETF

Let us say I want to establish a market neutral position. So if I buy 50 shares of stock (SPY) and I want to delta hedge, I sell an ATM covered call. So that brings the position delta to 0. Now, I ...
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81 views
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2answers
187 views

Why is the vega of an at the money option so insensitive to movements in volatility? I.e, why do ATM options have such little Vomma?

I've been trying to understand why at the money options have very little vomma. I was reading and came across a graph that showed vega as volatility changes and I couldn't grasp how the relationships ...
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1answer
73 views

European vanilla call/put option, when volatility increases, how will gamma changes?

according to the BS formula, $\gamma = \frac{N'(d_1)}{S_0\sigma\sqrt{T}}$, gamma will decrease when volatility increase. How does it intuitively make sense? rather than from the formula.
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0answers
136 views

Constructing Volatility Smile from American Options

My question is about best practices for reconstructing volatility smiles for a fixed tenor from American option data. For simplicity/liquidity, I am currently considering options on SPY. I am ...
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1answer
220 views

Bloomberg equity option volatility data

Using the Bloomberg open API, I am trying to program a C++ script that is able to download option volatility data from Bloomberg. I currently do not have access to Bloomberg, but in the coming week I ...
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1answer
102 views

Which volatility to use to price options on futures contract?

I have some questions regarding pricing futures options and I just want to be sure that my thoughts are correct. I am trying to price options on futures for american & european style. In the ...
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0answers
76 views

Volatility Surface Constituents, do's and dont's

Recently I have been working a lot with implied volatility and volatility surfaces. The basic idea is easy to follow: 1) Gather market prices of options at different (Strike,Expiry) 2) Calculate ...
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3answers
703 views

What does it mean to be “long or short in volatility”?

I've heard a question regarding pricing of european calls. The question is: Is the call long or short in volatility when it is (deep) OTM? What is the profile of the implied volatility? I ...
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1answer
98 views

What are the parameters of the function PORTVAR in Matlab?

According to the Matlab help, Portvar will give the "Variance for portfolio of assets" by entering the returns of the Assets and the corresponding weight. However, it does not explain the parameters ...
7
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1answer
901 views

Risk Budgets with Target Portfolio Volatility

I'm working through the implementation of a risk budgeting approach as described in the recent Roncalli paper. The idea is that the portfolio manager sets a contribution of total portfolio volatility ...
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2answers
54 views

Comparing Portfolio Volatility with Index Volatility seems a wrong method?

thanks for looking into this question. I am comparing an investment strategy against the S&P 500 for a financial article I'm writing. I compute volatility of the Portfolio in this way, as the ...
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1answer
90 views

I have volatility of a portfolio in year 1 and in year 2. How do I calculate the volatility over the total 2-year period?

thanks for looking into this question. See the picture below (better is right-mousebutton - open in new tab). I also have the price and return data of the Stocks if that's needed to calculate the ...
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1answer
30 views

Transaction Costs Measure ATOP: What does it mean and exactly measure?

I went through some presentations about LowVol strategies for some indices. In the presentations were tables with average returns, vola, Sharp ratio and ATOP. I have no clue what this ATOP is supposed ...
2
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1answer
178 views

Some questions about implied volatilities and how to generate theoretical prices when market prices are not available

I am building a little Excel file that take some option prices in input and plots the volatility smile/surface. I have a script that reads market prices from the option chain for 3 different ...
2
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2answers
474 views

How to calculate the volatility matrix with multiple stocks

calculating the volatility for a single stock is straightforward. However, I'm not sure whether my approach for calculating the volatility matrix for multiple stocks is correct: I assume a log-normal ...
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3answers
4k views

Relationship between Beta and Standard Deviation

I was doing some financial analysis on two firms in the coffee industry. After calculating Beta and Standard Deviation for both firms, I seem to have stumbled on some weird phenomenon. It appears ...