This past weekend, one of my favorite sportswriters, Allen St. John of The Wall Street Journal, had a fascinating article profiling the effectiveness of professional baseball's managers.

Contrary to the average fan's belief, many of the snap decisions that a manager must make in the course of a game -- when to employ a pinch-hitter, when to bunt, or when to send a player running to avoid a double play -- have a relatively small impact on the outcome of the game.

What really counts
St. John found instead that two other factors, often easily overlooked by fans, had a far greater impact on a team's prospects for victory. The first was a manager's ability to instill in his batters a sense of discipline at the plate. That trait, when properly practiced, forces the opposing team's pitchers to yield an inordinate amount of walks.

The second factor was a manager's effectiveness at pulling his pitchers from games at the appropriate time. This particular skill could best be attributed to accurately assessing a pitcher's "arm strength" and determining whether or not he still had the velocity and command of his pitches to face down the other team's batters.

I believe these findings can help the average investor in three ways.

1. Think long-term.
Just as average fans tend to place too much emphasis on short-term tactics like pinch-hitters, bunts, and steals, average investors tend to place too much attention on daily news items and quarterly reports.

Consider Whole Foods' (NASDAQ:WFMI) recent earnings report. By most accounts, things are just fine at the specialty grocer, but some minor issues sent the stock down 10%. There was similar trouble with Starbucks (NASDAQ:SBUX). All this might make for interesting talk on the investment-news programs -- the equivalent of water-cooler talk in the investment world -- but it has little effect on long-term results.

2. Don't ignore dividends.
Many investors, like some baseball managers, tend to overlook unsexy activities that are ultimately far more important to a portfolio's -- or a team's --long-term success.

In baseball, a few managers apparently dislike walks; they prefer instead that their players swing away at the plate. St. John says that in one telling comment, Chicago Cubs manager Dusty Baker once said, "Players who walk clog up the bases."

Well, these players "clogging" the bases actually end up scoring quite a few runs -- which, the last time I checked, was the whole point of the game.

In the same way, many investors are not fond of stodgy stocks that have modest annual returns but offer historically high dividends -- stocks such as PepsiCo (NYSE:PEP), Unilever (NYSE:UL), Altria (NYSE:MO), 3M (NYSE:MMM), and Johnson & Johnson (NYSE:JNJ).

Think of these stocks as baseball players who possess a lower batting average but have a high on-base percentage. They might not make the daily headlines as often, but they get results.

And just as walks lead to runs, which in turn lead to victories, so, too, do dividends translate into real profits, ultimately helping investors reach their overall retirement objectives sooner. And that, the last time I checked, is what most of us investors are trying to achieve.

3. Know when to let go.
The third similarity between good baseball managers and good investors involves knowing when to let go. In baseball, the best managers have an inherent knack for knowing when to pull a pitcher. They'll often leave in pitchers who've struggled through a tough opening inning, or pull a pitcher even though he has a one- or two-hitter going in the final innings.

The same skill needs to be employed in investing. If a given investment stumbles right after you bought it, do you sell it or keep it? The decision rests on an appropriate understanding of your investment. Did it get rocked by some one-time, unforeseen event from which it can recover? Or is it like a pitcher who just doesn't have his best stuff on a given day?

If it's the former, it makes sense to hang tough and stick with the investment. If, however, it's the latter, it's better to "pull" that investment sooner rather than later. Too often, investors -- like managers sticking with a pitcher -- are reluctant to admit a mistake. They'll end up holding on to an investment far longer than they should.

To carry this analogy one step further, the best investors -- like the best managers -- also know when to pull a star. In the investment world, it's easy to keep a winning stock longer than you ought to. After all, when a good stock has gotten them so far, many investors have an undue confidence that that same investment can be ridden all the way to retirement.

Sometimes this is true, sometimes not. If it appears that the "arm strength" of a given investment is dwindling, it is probably makes sense to pull that "star" investment and replace it with a "closer" that might yield a strong return in the next few innings.

Bottom of the ninth ...
It's been said that baseball is a lot like life. Upon reflection, I'd argue that it's also a lot like investing.

Just as the best managers sometimes have bad games and losing seasons, so will good investors have bad quarters and less-than-stellar years. But over time, if you demonstrate patience at the plate, learn to sell your underperforming stocks sooner, and teach yourself not to hold onto your good ones past their prime, you can increase your winning percentage and achieve your long-term goals that much sooner.

Whole Foods and Starbucks are Motley Fool Stock Advisor picks. Johnson & Johnson and Unilever made the cut at Motley Fool Income Investor , while 3M got the nod for Motley Fool Inside Value. Want to increase your portfolio's on-base percentage? Consider a free 30-day trial to any of our Foolish newsletters.

Fool contributor Jack Uldrich is a fan of Minnesota Twins manager Ron Gardenhire, despite Ron's "small ball" tactics. But Jack's really a fan of a "small tech" - such as nanotechnology - and small-cap stocks. He does not own any of the stocks mentioned in this article. The Fool has a strict disclosure policy.