Reasons Not To Use a Real-Time Market Scanner

Added on by C. Maoxian.

This section from @tagrtrades recent blog post caught my eye:

I’m slowly trying to move from a scalper to a bigger picture trader. The biggest catalyst to this change was letting the subscription to my intraday scanning service lapse and focus on my pre selected watch list. Sure I miss trades, but I know the trigger points I’m looking for and don’t find myself shooting from the hip nearly as much as I have in the past. I’m also trying to look at charts outside of just the 1-5min timeframe I’ve done for years. Pulling back and getting a clear hourly view has helped me look for areas where I can target for more than just a few cents and get more % out of each trade.

I've had a few thoughts about the pitfalls of using a real-time market scanner:

  • Information Overload

Even when you really fine-tune your scanner, it's still spitting out dozens of things to look at every day. There's just too much to look at. I have what I consider to be an incredibly rigorous set of criteria that has to be met to qualify as an "Unusual Suspect," and still I get at least a dozen candidates every day (today I got 18). If you're looking at everything, you're looking at nothing. The human brain can only focus on a few things.

  • Pavlovian Response

Every time the scanner dings, you get excited and think about making a trade. If you're looking at an intraday time frame like the three minute chart, you're going to start overtrading. You'll be generating a lot of commissions and very little profit, if any.

  • Liquidity Issues

I use the scanner to find "Unusual Suspects" in real time. They are generally low float, micro-cap junk stocks that are on a tear, (or they are bigger stocks that have been hit with news, good or bad (earnings, FDA decisions, etc.)).

The trouble with the low float, micro-cap junk is that after the initial burst of activity, volume dries up and there's no way to exit your position in a graceful way, even if you're on the right side of the market. You get stuck. And I mean stuck at a profit. It isn't as simple as crossing the spread and getting out. If you have 10,000 shares of a dollar stock, or more likely tens of thousands of shares, you just can't exit without tipping your hand, and they'll move the market away from you fast. It's frustrating. 

  • Dependency Issues

It's possible that you may shape your whole trading strategy around the scanner and grow overly dependent on it. I like to think that everyone should strive to be able to trade profitably while still using an old 14" cracked laptop on a dial-up connection from the Australian Outback.

  • Unnecessary Expense

I've always thought that your broker should supply you with a first-rate market scanner, gratis. My broker, IB, does have a pretty good market scanner, but it's nothing like Trade-Ideas, not even in the same league. Schwab probably uses the old CyberTrader technology for their scanner, but I really don't know. Fido, Schwab, TD, IB, etc. should all license the Trade Ideas technology and offer it to their "pro" users for free.

I might think of some more things later and update the post, but that's it for now.