Some intraday data series do not contain a buy/sell identifier for trades. As most estimators of transaction costs require this information, an algorithm is necessary to classify trades as buy or sell. When bid/ask quotes (or best buy/sell limit order prices) are available, a natural method is to compare the trade price with the quotes prevailing at the time of the trade. Trades at or above the ask (or best sell limit price) will be classified as buys, trades at or below the bid (or best buy limit price) will be classified as sells. This algorithm will leave trades within the quotes unclassified. Trades within the quotes may be either ‘crosses’ (trades negotiated outside the central market place) or trades where a floor broker or the order book improved on the price of the specialist’s quote, as often happens on hybrid markets like the NYSE. Lee and Ready (1991) show that this algorithm is very reliable and classifies most trades in the same way as the classification based on a comparison with bid and ask quotes.

I’ve mentored several friends and relatives in starting up small businesses. The first years were always a struggle, because they were trying to find ways to efficiently bring in new customers. Once a way was found, things got much easier. Developing a back end (i.e., selling other, usually more-expensive products to existing customers) is relatively easy, as is refining operations.

A typical business start-up of this kind will break even or lose a little money in year one, make a decent salary for the owner in year two, and provide a substantial bonus—in addition to a good, arm’s-length management salary—in year three. After that, it’s usually straight uphill.

I believe we are at the tail end of a nationwide real estate bubble. By any fundamental perspective, property prices have gotten out of hand. In some locations, this may mean a significant depreciation. In other, better locations (the Sun Belt, certain cities), it may mean a two- to four-year deflation of 10 percent or 15 percent. The worst depreciation will probably occur with condominiums, which are traditionally overpriced, overfinanced, and too heavily owned by speculators during bubble periods. That said, I’m confident that you will be able to find good real estate deals this year, next year, and each year thereafter during the downturn.

I’m no Donald Trump. I don’t even consider myself a professional real estate investor. I’m a professional marketer who has made real estate investing a nice sideline business. But in the 11 years that I’ve been doing it, my real estate portfolio has grown and grown. As an income producer, real estate has never failed to provide me with less than a very substantial income. As an asset builder, my rental real estate properties have all paid for themselves and provided me with a rate of return that is at least 10 times what I’ve been able to get from stocks and bonds.