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Illiquid Asset Investing 1. Liquidating Harvard

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Andrew Ang <strong>Illiquid</strong> <strong>Asset</strong> <strong>Investing</strong> <strong>Asset</strong> Management<br />

process only involves averaging returns for this period and the past period, then we can filter the<br />

observed returns to estimate the true returns, r t , from observed returns,<br />

1 * *<br />

rt rt rt<br />

<strong>1.</strong><br />

1 1 <br />

<br />

<br />

14<br />

*<br />

r t , using:<br />

Equation (2) unsmooths the observed returns. If our assumption on the transfer function is right,<br />

the observed returns implied by equation (2) should have zero autocorrelation. Thus, the filter<br />

takes an autocorrelated series of observed returns and produces true returns that are close to<br />

I.I.D. Note that the variance of the true returns is higher than the observed returns:<br />

1<br />

<br />

1<br />

var( rt) <br />

2<br />

2<br />

* *<br />

var( rt ) var(<br />

rt<br />

),<br />

since | | 1,<br />

so we are adding variance to the observed returns to produce estimates of the true<br />

returns.<br />

The unsmoothing process has several important properties:<br />

<strong>1.</strong> Unsmoothing only affects risk estimates and not expected returns.<br />

Intuitively, estimates of the mean require only the first and last price observation (with<br />

dividends take “total prices” which count reinvested dividends). 11 In Figure 2, we can see<br />

that the first and last observations are unchanged by infrequent sampling; thus<br />

unsmoothing only changes the volatility estimates.<br />

2. Unsmoothing has no effect if the observed returns are uncorrelated.<br />

11<br />

Technically taking means of both the right- and left-sides in equation (2) results in the same means in large<br />

samples.<br />

(<strong>1.</strong>2)<br />

(<strong>1.</strong>3)

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