Is the stock market more volatile than in the past? Many investors believe so based on the sharp intraday swings of recent days.

However, it really comes down to how you define volatility. If you look at the median monthly high-low ranges (in percent) for the S&P 500 index going back to 1980, and compare those averages to this year's values, only one month stands out so far.

In January, the range between the high and low was 13.70% (of the average of those two numbers), almost double the 7.60% monthly median going back 28 years.

The high-low range for this year's first month also topped previous highs of 13.09% in January 1987 and 12.62% in January 1980.

In Gold: play the shares, not the metal?, I noted the apparent disconnect between the performance of mining stocks and gold and suggested that the shares may represent a better bet in the near term.

However, there seems to be an even greater disparity in another part of the commodity universe. Over the past 10 months or so, crude oil prices have soared by more than 70%, while energy sector shares have only risen about 5%.

To be sure, there are valid reasons why the stocks might not always track moves in the underlying commodity.

For one thing, the largest energy firms (with the heaviest sector weightings) have fully integrated operations (e.g. they explore for, pump, refine and market petroleum-related products), so a rise in the price of crude oil may not flow directly through to their bottom lines.

As of Monday's close, the S&P 500 SPDR exchange-traded fund (AMEX: SPY) was down 12.25% for the year, buffeted by continuing turbulence in global credit markets and concerns over future growth prospects.

However, the relative performance of the major sector ETFs paints a far more confusing picture.

On the one hand, strength in materials and industrial shares, and weakness in the traditionally defensive health care sector, suggests that investors are not too worried about the outlook.

In contrast, strength in the consumer staples sector and weakness in technology shares indicates they are, in fact, concerned about what will happen to the economy.

So what does it all mean?

On October 31, the benchmark U.S. dollar-denominated MSCI All Country World Index closed at a record price of 427.63. It has since fallen to 366.21, a drop of 14.36%.

Yet not all world markets have fared equally poorly. Over the three-month span, there has been significant divergence between some of the best and worst performers, as the accompanying graph and table attest.

While it is hard to draw definitive conclusions, two things seem to stand out:

• Aside from Japan, which has been among the worst performing Asian markets for quite some time (and thus, has likely attracted considerable "bottom-fishing" inflows from value and contrarian-oriented investors in recent months), and Malaysia, which has remained a curious oasis of stability since global markets peaked, Asia-Pacific markets have not been been a popular investment destination lately. Perhaps we are witnessing the unwinding of ill-fated "decoupling" trades?

We're in a rare moment in history where cash is king. That may sound like a cliche, but I think the 4% to 5% returns you can get in a money market account are very attractive compared to the risk you take by staying in stocks. My prediction is that the Standard & Poor's 500 could fall at least another 10% from here. I think the economy is weakening and the crisis in the credit markets will worsen from here.

As I explain in this video, I think this is not the time for a buy-and-hold strategy. But if you must stay in stocks, look at more defensive sectors like food, beverage and healthcare. Gold is another sector that could potentially provide a safe haven in the tough months to come.

Michael Panzner is a 25-year veteran of the global stock, bond, and currency markets and the author of Financial Armageddon: Protecting Your Future from Four Impending Catastrophes and The New Laws of the Stock Market Jungle.

Based on an analysis of data from 1979 - 2005, the next four-to-six weeks has been a seasonally weak period for the Nasdaq Composite index and the Russell 2000 index relative to the S&P 500 index.

While it's hard to say for sure why those two measures have tended to underperform the broad market around this time of year, several possible explanations come to mind:

• Pressure from mutual funds cutting losing positions in volatile or thinly-traded issues before the books are closed at the end of October

• Asset allocation shifts in favor of larger, more defensive shares amid uncertainty over back-to-school sales and the upcoming holiday selling season

• Attempts by traders and portfolio managers to cut risk exposure and dampen portfolio volatility as the time approaches for end-of-year bonuses to be decided

Of course, seasonal factors aren't the only driver of share prices, and the pattern this year could turn out altogether different than in the past.

Nevertheless, the possibility that small cap and Nasdaq shares could lag other issues in the weeks ahead is something worth keeping in mind.

Michael Panzner is a 25-year veteran of the global stock, bond, and currency markets and the author of Financial Armageddon: Protecting Your Future from Four Impending Catastrophes and The New Laws of the Stock Market Jungle.

Nearly all of the major stock market indices are "capitalization-weighted" (one notable exception is the Dow Jones Industrials Average, which is "price-weighted").

That means swings in the value of the largest constituent members have a proportionately greater influence on the price of the relevant benchmark than price changes in the shares of smaller companies.

In many cases, exchanges and financial services firms have also created "equal-weighted" versions of some of the more popular bellwethers (many of which also serve as the basis for certain exchange-traded funds, or ETFs).

With this type of structure, the equivalent percentage move in the price of a share of any company in the index, regardless of the firm's size, will have an identical impact on the value of the benchmark.

Because of the way each index is calculated, one can get a feel for whether or not a market trend has been broad-based, and thus "healthy," by examining the ratio of the price-weighted index to its capitalization-weighted equivalent.

Lately, sentiment towards the U.S. dollar has grown increasingly negative and American investors have continued to weight portfolios in favor of overseas markets.

Yet, despite all the bearishness, the greenback has managed to recover smartly from its April lows.

In fact, on a technical basis, the U.S. Dollar Index, which reflects the unit's value against a basket of six other major currencies, has made what appears to be an important bottom. With the recent move upward through a key downtrend, the currency seems poised to rally even further.

One reason for the turnaround may be the prospect that U.S. interest rates will continue rising instead of falling, as many marketwatchers had been expecting only a short time ago.

Nervous profit-taking by some holders of foreign securities looking to lock in substantial paper profits, as well as short-covering by frustrated short-sellers among the large contingent of dollar bears, may also be contributing factors.

Finally, there may be "safe haven" buying of the greenback taking place on worries that global markets and geopolitical conditions are becoming increasingly unsettled.

Whatever the reasons, it's time to reconsider an overly negative stance on the U.S. currency.

Michael Panzner is a 25-year veteran of the global stock, bond, and currency markets and the author of Financial Armageddon: Protecting Your Future from Four Impending Catastrophes and The New Laws of the Stock Market Jungle: An Insider's Guide to Successful Investing in a Changing World.