Investors need to understand their true reasons for staying in the stock market as it continues to make new highs, suggests MoneyShow's Jim Jubak.

For the week ahead, what I'd like you to do is plant your feet, sit up straight in yoga position, and contemplate...well, not your navel.

Don't think about deep breathing. Think about what's up here. Think about how you're feeling about the stock market. We're interested in your psychiatry as an indicator of well how other people are thinking about the market, because really the continuation of this rally-or the end of this rally, or the turning of a rally into a decline-right now, I think, is really all up here.

Now the question is, are you one of those investors who are in this rally basically because you're afraid to get out? You may have missed part of it, so you may think there's more to run? You may be lagging behind your neighbor Fred and your neighbor Sally, so you're in the market basically because you're afraid not to?

I think there are a lot of people like that. You have a lot of professionals who went through 2012 trailing the indexes. They're afraid to do it again. So for them, the question is how long you stay in there. I think there's a fairly large group that is going to stay in the market really until they get kind of discouraged or convinced otherwise.

So right now we're sort of bouncing along; we're not moving anywhere. The Dow, which has been up day after day after day, is managing to just climb a few tenths of a percentage point to keep the string going. But we're certainly not seeing a whole lot of action.

And in the background, we're seeing worries build up. We've got worries about Europe. In China, the central bank seems to be back in anti-inflation mode. Japan...well maybe Japan's not going to cut rates as much as we thought. So you've got a sense of the world getting a little riskier. And on the other side, all you've really got is faith in the rally, a belief that you don't want to miss it.

So how do these two things work out? That's what we're really watching over the next week, and the best indicator of that is your own mind, your friend's minds, what you read in the press.

The question is when you start to see this turn-when you start to see people go, "OK, I think the risk of staying in at all-time highs is more than I'd like to put up with, so I'm going to take the risk that I miss out on the rally," and move some money to the sidelines-if that starts to happen, the kind of very, very incremental increases that we're seeing will start to turn into incremental declines.

That will really test people's faith. And that's what we're looking for right here.

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