There’s a persistent, predictable relationship between the liquid and illiquid real estate markets: private-side real estate valuations respond more slowly to changes in market conditions than do public-side valuations, so the values in private, illiquid markets typically lag public market values by two to five quarters on average, depending on whether participants in private markets are evaluating market conditions by looking at completed transactions or at property appraisals. Correcting for that lag can give you a pretty good sense of whether a public/private arbitrage opportunity has arisen.