The theory is that by correcting for autocorrelation, you are uncovering a "true" return from a series of observed returns that contain illiquidity or manual pricing effects.
Return.Geltner(Ra, ...)
$$R_{G}=\frac{R_{t}-(R_{t-1}\cdot\rho_{1})}{1-\rho_{1}}$$
where $\rho_{1}$ is the first-order autocorrelation of the return series $R_{a}$ and $R_{t}$ is the return of $R_{a}$ at time $t$ and $R_{t-1}$ is the one-period lagged return.
Geltner, David, 1991, Smoothing in Appraisal-Based Returns, Journal of Real Estate Finance and Economics, Vol.4, p.327-345.
Geltner, David, 1993, Estimating Market Values from Appraised Values without Assuming an Efficient Market, Journal of Real Estate Research, Vol.8, p.325-345.
data(managers)
head(Return.Geltner(managers[,1:3]),n=20)
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