Are U.S. stocks tracking Asian markets?

— -- Q: Have U.S. markets been following Asian markets lately, or the other way around?

A: If you want evidence of the global economy, you can see it on a stock chart. U.S. and Asian markets are increasingly tied at the hip.

Your question is an excellent one. Giving a full and complete answer could be the topic for a doctoral dissertation, and perhaps it already is one. There's been some work done in the area, if you'd like more details you can check out a study on interlinked global markets.

But for just a quick-and-dirty analysis, investors can put exchange-traded funds that track Asian and U.S. stocks on the same stock-price chart to see how the two interact with each other.

You can use USATODAY.com's free stock charting tools to do the comparison. Type in AIA in the Get a Quote box at money.usatoday.com to get the snapshot of iShares S&P Asia 50 Index fund. Select the Charts tab and below the graph in the Symbol Compare box enter SPY and Update Chart.

The first thing you'll notice is that the two ETFs have moved very similarly within the past year. This is consistent with academic research indicating that markets of different countries are increasingly moving in lockstep with each other.

However, there are two important other things to note from the chart. First, notice how the Asian stock ETF was first to top out and start to decline in February 2011, and how U.S. stocks followed that decline.

The Asian stock ETF, meanwhile, is more volatile than the U.S. ETF. The ups and downs are more extreme and violent.

So it would appear Asian stocks and U.S. stocks, at least recently and using these two indexes, are somewhat closely related. But the Asian stocks tended to be the first to crack earlier this year and continue to deserve their reputation as being more volatile.

Matt Krantz is a financial markets reporter at USA TODAY and author of Investing Online for Dummies and Fundamental Analysis for Dummies. He answers a different reader question every weekday in his Ask Matt column at money.usatoday.com. To submit a question, e-mail Matt at mkrantz@usatoday.com. Follow Matt on Twitter at: twitter.com/mattkrantz