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Volatility and MicrostructureSome thoughts and a review of the literature
Introduction
Microstructure aspects can be safely ignored at longer horizons They are however first symptoms of market asymmetries First port of call for Private information ( as soon as the order is entered) The research topic has hardly been explored in the Indian markets
despite the financial markets being deep and widely traded Volatility in Prices seen as carrier of Information ( Filtration set) as
information is carried in Prices esp during Price Discovery and in Volumes traded (Information about demand)
Global research in the areas of volatility and microstructure in financial markets a salient area since the 80s
Microstructure as Volatility
The structure of markets ( Continuous Double Auction Markets in BSE and NSE) lead to typical effects in the microstructure.
However once the latent effects of non synchronous trading are detected and taken care of in the data (spurious correlations) from Non Synchronous trading (high frequency noise) U shaped serial correlation in price volatility
Volatility emerges as a key effect of the Price discovery and Order execution processes: The price effect of volatility The volume effect of volatility
The study of Price trends and Efficient Markets All forms of Market Efficiency rely on Price reflecting public and private
information in prices As a construct, the Efficient Market Hypothesis continues to be a
bulwark of Financial Markets research The existence of Price and Volume based trends and the existence of
trading around a denomination of Fundamental Value drive trading algorithms and informed Human traders to the market for every trade in Financial markets (Electronic exchanges, OTC markets and trading floors) in Currencies, Equities, Derivatives, Fixed Income or Credit and complex derivative combinations of these to satisfy the need to price and exchange risks and with the underlying motivation of a (fair) profit
Model of Asynchronous trading
Lo and Mackinlay, created one of the first micro models for focusing on the return generating process of N securities
In the absence of trading frictions or institutional rigidities , we can assign a virtual return rit (CCR)reflecting company specific information and economy wide effects for each security i
These virtual returns, intuitively differ from observed returns because of trading frictions.
Lo and Mackinlay assume a non trading probability it in each period t, assumed a s a IID sequence of coin tosses independent of the returns rit
rito , the Observed return of the security can be set to 0 if there is no transaction as rit
o = ln (pt/pt-1), thus if we consider 5 periods consecutively in which the security trades only in 1,2,5, the security reflects the same virtual return till period 2 and then observed return is 0 for 3 and 4 to get the 5th period return accumulating that of 3 4 and 5
Lo and Mackinlay
One factor linear model for returns: ri = I + ifi + it
f is a 0 mean common factor and is idiosyncratic noise, both independent of all leads and lags and f(t) Is independent of (it-k)
We use non trading probabilities to designate two new RVs The first one is 1 while it does not trade while X is switched to 1 only
when the security trades
The duration of non trading k can then be expressed as a Product of all the delta consecutively, and observed returns a re a function of X
This duration can be expressed as E(k) = pi/(1-pi), Var(k) = pi/(1-pi)^2 The variance of observed returns and other moments are thus:
With a security with non zero expected returns, variances are dilated and negative serial correlation induced decays geometrically
The minimum autocorrelation as pi varies from 0 to 1 is achieved at Min Corr(rit
o, rit+1o)=-(CV/1+1.414*|CV|)^2
At Pi= 1/1+sqrt(2)|CV| This spurious autocorrelation can be generalized and erased from a
portfolio of securities to reflect common news reflected in illiquid securities with jumps
Bid-Ask Spread
Roll (1984) If P*(t) be the fundamental value in a frictionless economy and s be the spread,P(t) = P*(t) + I*s/2Where I is IID in +1 for buyer initiated trades with p=0.5
and -1 for seller initiated trades with p = 0.5Thus Change in Price = P = I(t) – I(t-1)*s/2Here, the second moments of the process areVar(P) = s2/2 , Cov(one period) = - s2/4, Cov k period k>1 = 0Corr( one period) = -1/2 This intuition can be used to price the spread a s new information is produced for
the security
Ordered Probit Model
Lo and Mackinlay (1992) go on to present an ordered probit model which allows volatility to be modeled in generally conditionally heteroscedastic models and maps discrete time to continuous time assumed for price functions
This is solved using MLE and conditional volatility coefficients are squared to ensure non negative volatility
Others: Barrier Models by Cho and Freres and Marsh and Rosenfeld model transactions as
achievement of new discrete Price barriers, mapping the tau interval of trading Rounding models (Gottleib and Kalay 1985) Glosten and Harris (1988) – A permanent adverse selection component is present in
the data on bid ask spreads 43% adverse selection, 10% inventory holding costs and 47% transaction processing
Kyle Measures and Order Flow
Current literature on Microstructure still uses first principles. Intuitively measures of Order flow (Bid Volume – Ask Volume) are the
most appealing The latest measure by Easley and O Hara in PIN or VPIN measuring
Probability of Informed trading and Toxicity of the Order flow. These measures initially helped explain a lot in High Frequency traded
markets in High Frequency Data PIN measures are updated daily with methodological variants likely to
ensue in the future and also likely to be used by us in our work in this term
Volatility Spillovers and Cross Market movements Global integration of markets marked by a literature spanning the last decade
measuring commonality in movements between global indices The literature shows obvious relations for dependent economies with the Dow
index . Some literature also assumes a strengthening commonality of market moves a sign
of progress Spillovers more interesting in Cross asset moves and hard to measure by
cointegration . Currency markets to non traded financial asset markets most affected by equity and
derivatives markets trends Without spillovers, yield curves can measure and predict foreing exchange
premiums (Ang and Chen, 2010) These predictions exhibit low skewness and low correlation with carry returns
News Impact Curve and GARCH models Engel’s original study of volatility and its econometric measures guided
by and impactful is assessing the News impact of volatility of markets while they assimilate information
A current study of news transmission and efficient price transmission in markets may be handled by a microstructure approach
However microstructure approach effects of discrete markets already available to discount from price and trading data
Arrival of news studied thru event studies a distinct class of analysis that show the literature’s play with news arrival and assimilation at a larger level
Market Orders vs Limit Orders
A buy order is at a higher price than the mid rate, a sell order is at a lower price than the mid rate
The early literature has assumed Market Orders signal informed trading as the orders typically demand instant liquidity as if they have an expectation of price (gains)
However this is changing as most mature markets in the trading zone convert into Limit orders even if Market orders signal arrival of new information.
Thus Limit orders are not only suppliers of liquidity but also arbitraging off the availability of fundamental value and can be classified
The measures of illiquidity
It is generally known that if you take the effects of both price component of liquidity and volume effects of liquidity you can mirror the intuition of less traded stocks/assets also identifying significant Private information available in the security vis a vis a general non interest in the stock/asset
Amihud and Mendelson and Hasbrouck and Gideon Saar set early benchmark measures to determine the illiquidity premium
Asset pricing and the bid-ask spread
Amihud and Mendelsen 1986 The bid ask spread reflects the cost of execution and is found to be
negatively related to trading volume and the stock price continuity First to reflect the increasing bid ask spread as the return premia
observed in the returns Clientele effect implies here that longer horizon investors choose
securities with a higher spread Slope of the return spread relationship decreases with the spread Amihud (2002) time average absolute return with Dollar Volume of
Trading
Assymetric information measures
Early measures quoted by Hasbrouck relate the Asymmetric component with the plight of an uninformed dealer having to make market order trades including the work of Kyle (1985) and Glosten and Milgrom(1984) as well as the earliest work of Easley and O Hara (1987) and Glosten and Harris (1988)
The effect of inventory is available on specialized trading platforms aka the NYSE with a contemporaneous and subsequent price impact
The Glosten and Harris measure ignores inventory The quote revisions are treated as serially correlated with the quote revision
attributed to the assumption of trade event belonging to an informed trader, assuming an Inventory state as white noise I=- t
q(t)-q(t-1)= v(t) – v(t-1) – Beta(I(t)-I(t-1)) Demand is then modeled as a moving average of the white noise terms
Liquidity Risk
Acharya and Pedersen(2005) Liquidity is risky and is modeled for individual stocks with a common market
component A Liquidity CAPM is drawn up using the ILLIQ premium C/P for C in transaction costs
and P the current price, return r = (D-C’+P)/P(t-1) Here Dividend is modeled as D-C Similar measures of illiquidity and return are aggregated for the market component The market return & stock return increases with the covariance of market and stock
liquidity, Covariance between market liquidity and stock return negatively impacts the
idiosyncratic return (Pastor and Stambaugh, 2003) Thirdly, investors accept a lower return on the liquid securities
Paper goes on to realise a differing role for the persistence of liquidity Return also decreases with previous year’s volume and increases with spread Bekaert (2003) implies illiquidity directly predicts returns in
emerging markets This may or may not be a temporary condition The original volatility feedback effect is rarely documented in this
literature . As Expected returns increase the increase in required returns depresses the current state of Price functions for the security
Michael Brennan
Brennan goes on in a series of studies linking volatilities in debt to a higher peg than in emerging market and foreign equities
In Brennan Huh and Subrahmanyam (2013) authors build on the earlier validation of the Amihud (2002) measure
They also build on their study of the symmetric Kyle measure in Brennan et al (2010) where they find only seller initiated trades reflect a relationship ( trade at bid prices) (relation between return and changes in illiq)
Thus they decompose the Amihud measure for down markets and up markets
Half Amihud measure is strongly priced in the cross section of returns on down days
Liquidity and Asset Prices Amihud, Mendelson and Pedersen(2005) Measures in the impact of the volatility feedback effect with higher expected
returns depressing prices on reduction of liquidity It can be assumed in general that hard to trade securities are trading at hard
positive discounts to their fair value This series of literature thru 2013 reflects a desire to patch up Asset pricing
anomalies(Small Firm effect and others) using the liquidity risk priced in the microstructure including Brunnermeier, Acharya , Pedersen, Subrahmanyam and Brennan
The Paper merges different sources of (il)liquidity Transaction costs ( exogenous), Demand Pressure ( hitherto inventory risk, not in CDA markets) Private Information Order flow and search frictions
Price Formation
Joel Hasbrouck(2003) studies ETF and index futures trades Volumes positively impacted on a large scale by presence of Index
ETFs , Futures and exchange traded sector funds Traded on Open Electronic Limit Order Books (available outside the
‘floor’) A natural offshoot of trading for liquidity traders interested in
diversification Pennacchhi(1993) and Admati and Pfeiderrer(1988) Brennan and Xia study Macroeconomic effects aas real interest rates on
different categories of stocks demarcated by Sharpe Ratio measuring the impact on Pricing thru Discounted Cash flows
Probability of Informed Trading
Easley, Hvidkjaer and O Hara Tools are also readily available in R for this measure Initial validation paper with Engle and Wu in 2002(2008) Bivariate Autoregressive intensity process
Arrival rates of informed and uninformed trades Market Liquidity , Order Depth and Order Flow Daily conditional rates construct forecasts of the PIN measure PCA of PIN reflects a dominating impact of the systemic liquidity factor
Order Arrival used in a GARCH like process fitting to liquidty based returns
PIN
Measures components of order imbalance Order flow information
Impact on market Depth Liquidity
Price impact of transaction used as barrier to measure number of buy trades required to reduce Price impact below barrier(HDFC Bank never exceeds 0.6%)
These PINS may be high before earnings announcement on expectations and lower in post announcement trading as Private information converts into public information
PINs work in a smaller time window in event studies (+/- 7 days) Bad News with probability delta and Good news with probability 1-delta
(analogous to the Lo and Mackinlay measures)
PIN
Reflect the same concern with a delineation of only two types of traders,uninformed = liquidity traders
Probability of news measured as alpha Both traders modeled as Poisson processes with mu and epsilon arrival
rate parameters Expected(Total Trades)
Order Imbalance
PIN results
High turnover stocks exhibiting continuing returns continue to show returns unaffected by earnings events if they have high PINs ( liquidity)
They may have low PINS in this case they are subject to return reversals High PIN stocks thus consistent with High Private information passing to
uninformed dealers keeping up returns Uncertainty in Zhang (2006) also shown to work with PIN
Information uncertainty (Zhang 2006) Blume, Ohara and Easley Stock price continuations studied in market literature A sequence of stock prices reflect information and a single price does not reflect
underlying information Information is revealed slowly because of higher information uncertainty In high Uncertaainty , as expected from the volatility feedback effect , the required
positive returns on good news increase but the negative impact of bad news is minimized
Volumes can however not contribute to dissemination of information. Can be shown that volume correlated the quality of information being supplied to
changes in expected prices/returns One period model of trader demand ( needs explanation) Zhang uses Firm age and Coverage as parameters in uncertainty model woth analyst
dispersion and SIGMA(volatility) as well as cash flow volatility
Trading Price jump clusters
Novotny , Petrov and Urga (2014) Cluster of Price Jumps in Yen and Euro around tapering news and
Abenomics/ECB releases of liquidity Assessment of trading oppoirtunities represented by price clusters Show that Bid ask spreads eat into the returns The market makers mark-up the short-term (overnight) implied volatility at
the foreign exchange markets as the uncertainty increases and the impact of the announcements may increase the realized volatility Verdelhan(2010) risk aversion rises around news announcements ( News
Impact relation with higher volatility) Liquidity shocks timed with market news except for temporal inefficiencies
provided by central banks
News and Sentiment
Paul Tetlock study of the WSJ broadcast ‘Heard on the Street’ column Negative sentiment as posited by author or Spreads
Stop Loss Rules
Kaminsky and Lo Can substantially reduce volatility Can substantially increase expected returns
Impossible Frontiers
Market portfolios do not all end up with positive weights At least ten per cent combinations include short sales positions Is that a microstructure component?
12
Using High – Lows and Variance
Corwin and Schultz (2012) Bid-ask spreads can be estimated from Daily highs and lows The Daily high is almost always a buy The Daily low is almost always a sell The difference is an indicator of the daily variance Variance is proportional to the return interval(chosen) Spread estimates can be developed from these high-low differences Comparable with Roll(1984) spread estimators Hasbrouck’s(2009) Gibbs estimator computer intensive
ARCH like estimator
Different costs on the Bid and Ask side of the Market
Earning from the Bid Ask spread
Menkveld 2013 HFT can trade assets cross markets and earn spreads as passive traders Akin to liquidity making trades as quasi market maker In Continuous Double Auction markets, traders need not be market
makers Yet Bid Ask spread can earn them a steady income without crossing the
spread and in volume trades that can be sustained by new information IN US and Europe share of dominant stock exchanges down to 20%
Two scale realized Volatility
Recent research by Zhang, Mykland and Ait Sahalia(2002) Using squared returns as volatility indicator Non parametric estimation Breaks down realized volatility and allows reconciliation to implied volatility Y(it) = X(it) + e Sum of squared returns then switches to
Use overlapping sub grids from t(k-1) with different time intervals(scales) The presence of ht as endogenous to realized volatility
Ait Sahalia et al
To estimate the leverage effect in volatility and differentiate/integrate the leverage and the volatility feedback effect
Related to high frequency estimation of volatility
Future Directions
Berger and Yang estimate Frontier Markets diversification benefits, showing idiosyncratic variance more than ½ of the total variance in Variance decomposition analysis
Marshall, Nguyen and Nuttawat(Advance) Frontier markets have high transaction costs ( Illiquid spread)
Bandi et al _ Realised Volatility vs Implied Volatility Traders use different Volatility estimates
Cornell and Green (!991) Spread to Price Performance of High yield Bonds
Signal or Noise
Banerjee and Green develop a model to recognize whether traders are informed ( rather than just liquidity makers and takers)
They relate the phenomenon back to volatility clustering Stein(2013)talks of traders inability to recognize other traders’ motive
as creating two externalities- One is the spread moving away from fundamentals and the second is a fire sale effect
Private Information
M U and J shaped patterns in FX spot markets Patterns in bid ask, trading volume and return volatility outside noise Strong relationship between Cumulative order flow and exchange rates (Easley) Unanticipated deviations from intraday trading volumes Bilateral relationships between volatility and volume, volatility and bid ask
spreads McGroarty et al study the introduction of the Euro and relate anticipated
and unanticipated order flow and volume and all three with bid ask spread Best bid and ask orders per second with trade data Log prices and log squares (volatility) Total Volume from Bid and Ask trades added
Measures of Private Information
Order Flow
Volume
• Expected Volume not linked to market making , yet a basic ‘inventory’ available in all traded assets
Relative liquidity as a future information measure Valenzuela et al(advance) Quoted depth distribution in the Order book at different times Indicator of consensus on traded price ( can be extended to other measures of
price /valuation stability) Higher liq provision away from the book
Disagreement on current price High volatility (intuition) Exploration/spurious orders from a high volume investor/trader
PCA used to identify the important quotes in the book Use Ait Sahalia, Mykland and Zhang TSRV Goettler Parlour and Rajan, Frequency of quotes waiting at the traded price
Volatility thresholds
Kasch and Caporin 2013 Correlations increase during high volatility periods reducing
diversification effects Dynamic behavior of cross correlations during switching of regimes Volatility threshold using both Conditional volatility h^1/2 and
covariance matrix The threshold Xt above which the variance becomes instrumental in
cross correlations, Not like increased cross correlations are not contagion
Idiosyncratic Volatility
Stock specific/Name specific volatility Can be an indicator of acquisition premium and higher market premiums
in Information poor economies
Volatility and Market Depth
Ahn Bae and Chan, Transitory volatility rises and then declines on increase in market depth
Depth increases due to increase in Limit Orders The TV affects mix between limit and market orders These limit orders arise without market making yet provide liquidity Earlier studies on superdot orders helped Hasbrouck identify migration of buyers to
limit orders and the phenomena of fleeting orders Potential loss from trading with informed trader(“market orders”) Foucault game theoretic model of a limit order market Glosten(1994) Patient traders: Limit Orders, Urgent traders ( Market orders) Limit Orders have to be wider spread to avoid market traders/informed traders in high
volatility markets
Order Book Slope and Price Volatility
Duong and Kalev (2008) Negative relation between future volatility and variations in the liquidity
provision in the order book Order book slope of the buy side more informative Institutional orders more informative Requirement of anonymous markets proved in ASX Indian markets proved to be anonymous Frontrunning minimized in anonymity yet information available in the
order book transforming private information to public information
Trade Autocorrelation
Chung and Li Using PIN measure Price impact of trade Positive correlation in direction of trade Both measure positively related to trading frequency Quote revisions earlier studies also because of liquidity, inventory and
non information reasons PIN better measure than use of small firms and liquidity proxies Kyle study initially on trade size and pace of information assimilation Institutional trading may contribute more to clustering during high
volatility before a news break
Volatility of Liquidity
Volatility Feedback Puzzle (Bollerslev) resolved microstructure: Zhang and Perreira 2010
Liquidity influences returns beyond trading costs Liquidity modeled as stochastic price impact Liquidity Premium = Additional return necessary (Adverse Price impact
of trading) Not required for patient investors waiting on Limit Orders Zhang and Perreira go on to use a CRRA risk aversion model Granger causality from Price impact to trading activity
Volatility discovery across the LOB Wang(2014) Using trading in both stock and options markets A new picking off risk in limit orders different from adverse selection because of
Private information Informed traders use Limit orders established in the literature
Informative of future liquidity Directions of future stock price movements Future stock price volatility
Price aggressiveness of the Limit Order Book Winners Curse Aggressiveness of limit orders related to Options Price trading Infer volatility from Options prices and change the aggressiveness of the Limit order
book
Emerging Limit Order Market
Jain and Jiang(2014) Information content of the Limit Order Book on the Shanghai Stock
Exchange LOB consistently predicts future price volatility from the slope of the
order book Sell orders become more informative during extreme wide movement
days ( higher no. of extreme moves on the Shanghai stock exchange) Buy orders more informative during normal market and up move days Order submission strategies
Sentiment
Berger and Turtle(2015) Short term increases in sentiment precede positive returns Sustained increases in sentiment precede negative returns Especially true for market portfolios and Opaque portfolios with high
uncertainty and/or higher arbitrage for private information and greater frictions
Sophisticated investors /arbs contribute to mispricing Build up of short interest usually quieter than the behavioral bias in
buying Diminishing bubble growth rate
Indian trading/investing relations of liquidity Simultaneous price discovery in Banknifty options and futures markets Large price moves across a bid spread and Price impact spanning Bid –
Ask pf 300 to 500, Price impact of 25*200 per lot in a single move Actively traded with large volumes Selling Puts in a monotonically rising trend Risk induces trades on the other side, ensures high spreads and low
volume ( in no. of lots) trading Most of the float from Public sector banks
Continued Bayesian inference
Sequential deterministic modelling updated for new information LOB as an information store Information lost between the cup and the lip restored by Bayesian inference Information to trade conversion based on Matching engine and order flow Heavily traded securities can reveal the patchwork First in First out at best prices First few levels are broadcast, all levels are available readily ( except of some
exchanges) Adds, Modifies and Cancels Explicit vs Implied ( Hidden/iceberg) Off book trades / Bulk trades mechanisms
Price Discovery and Liquidity
Impact of information arrival Newswires on intra day movements Riordan et al(2013) Impact on liquidity and trading intensity Liquidity decreases around negative messages ( May increase on lower
prices) Negative messages induce stronger reactions
HFT data increased the study of such trading by HFT traders Hoffman, fast and slow traders
Latency
Hasbrouck and Saar (2011) Technology of trading Easy execution Flash crash potential from mistakes Reduction in transaction costs but increase in spreads
Microstructure related increase in concentration effects Highly concentrated industries with low competition feature more
abnormal returns factoring product market cash flows in financial markets
Competitve industries see far lower risk premiums and abnormal returns Industry concentration links to behavioral phenomena in the
microstructure
Frontier markets and idiosyncratic risk Berger and Yang(2013) As mentioned earlier far away illiquid markets good idiosyncratic risk
proxies Frontier funds more illiquid extensions of emerging markets 1/3 of fund risk idiosyncratic for Frontier funds and ½ of regional funds,
commonality decreasing The criticality of index proxies for Passive investors in Emerging Debt
trading Marshall, Nguyen et al fixate on transaction costs (Bid Ask spread) that
negate such diversification (Liquidity risk) Chunky Price moves
Returns in Private Equity ‘ Markets’
Ang et al 2014 Model Partner cash flows Unbalanced panel and Time varying PE premium ( Liquidity and chunky
transaction moves and related risk measures)
Limit Order Markets Parlour and Seppi (2007) LOMs : No Uniform clearing price Each order filled at limit Market orders changed to limit after partial fill (exchange
characteristic/manual in India) Iceberg orders in the interest of market disclosure ( during sells) In India cannot choose as exchange after large order arrives (market order)
at least technically Dynamic trading strategies ‘ also’ depend on monitoring changing market
conditions ( frequency of monitoring) in news and transaction volume terms Seen as fair in light of adverse selection frictions Asset valuations now a social activity in Economics because most economic
assets have trading proxies Coordination problems ruled over by ease of anonymity