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Michael Mauboussin: Two Tips to Improve The Quality of Your Decisions

Michael Mauboussin, chief investment strategist at Legg Mason and our first interview on the podcast, offers two simple techniques to improve the quality of your decision making: a decision journal and a checklist.

1. Create a decision journal and starting using it. 

Many years ago when I first met Danny Kahneman, and Kahneman is one of the preeminent psychologists in the world who won a Nobel Prize for economics in 2002, even though he's never taught an economics class.

When I pose him the question, what is a single thing an investor can do to improve his or her performance, he said almost without hesitation, go down to a local drugstore and buy a very cheap notebook and start keeping track of your decisions. And the specific idea is whenever you're making a consequential decision, something going in or out of the portfolio, just take a moment to think, write down what you expect to happen, why you expect it to happen and then actually, and this is optional, but probably a great idea, is write down how you feel about the situation, both physically and even emotionally. Just, how do you feel? I feel tired. I feel good, or this stock is really draining me. Whatever you think.

The key to doing this is that it prevents something called hindsight bias, which is no matter what happens in the world. We tend to look back on our decision-making process, and we tilt it in a way that looks more favorable to us, right? So we have a bias to explain what has happened.

When you've got a decision-making journal, it gives you accurate and honest feedback of what you were thinking at that time. And so there can be situations, by the way, you buy a stock and it goes up, but it goes up for reasons very different than what you thought was going to happen. And having that feedback in a way to almost check yourself periodically is extremely valuable. So that's, I think, a very inexpensive; it's actually not super time consuming, but a very, very valuable way of giving yourself essential feedback because our minds won't do it normally.

2. Use a checklist. 

Mauboussin: So the best work on this I've seen is by Atul Gawande, who is a surgeon in Boston who wrote a book a couple of years ago called The Checklist Manifesto, and one of the points he makes in there is that when you go from field to field, wherever checklists have been used correctly and with fidelity, they've been extremely effective in proving outcomes. So we all know none of us would step on an airplane today without the pilot having gone through the checklist. It's been a big move into medicine, especially for example, in surgery where checklists have really made substantial inroads in reducing infections, for example, and hence mortality, and other areas like construction elsewhere.

So the question is, how do you become more systematic in applying what you know? And I'll just mention one other thing on this. There are two; Gawande talks about two kinds of checklists. By the way, this branch is right out of aviation. One is called a do-confirm checklist, a do-confirm, and that just basically says, Hey, just do your normal analysis the way you've always done it and been trained to do that, but stop periodically just to confirm that you've covered all the bases. So as an analyst that might say, hey, I'm going to do a really thorough evaluation work. I might look very carefully at return on capital trends. I might study the competitive strategy position. You are just going to do all that stuff, but you're going to stop every now and then, just to check to make sure you've done everything.

The second one is called, the second kind of checklist, is called a read-do checklist. This is when you get into a difficult situation, for example you're a pilot and one of your engines goes out, the redo will guide how you should approach that problem. So you don't have to think about it so much, you just sort of go through it systematically. And so for an investor that might be hey, what happens when a company misses a quarter? What happens when they have a negative announcement or an executive departure? Sometimes that means sell the stock. Sometimes that means buy more. Sometimes it means do nothing, and a read-do checklist can help guide some of that thinking as well. So it's really a way to be structured and consistent in your analysis.