NYSE Reversal Indicator
The NYSE Reversal Indicator uses the advance/decline ratio with a stochastics overlay. The bottom half of the chart is the weekly candles of the S&P. The chart itself goes back two years. Some folks have criticized me for posting this chart in the past saying that it isn't 100% accurate - but if it was, as some think it must be, in order to post then 1) I wouldn't be posting it - I'd save it all for myself, or 2) I would sell it to a major brokerage firm for an ungodly sum of money. But it isn't perfect (I wish it was) and there is always a level of error that you can expect from it. But overall, it is fairly accurate, and when the indicator hits certain extremes on the stochastics, it is often a good time to start hedging positions that are going against the direction of the indicators, or start loading up on short or long positions in respect to the direction that the indicator itself is pointing to.
Remember, the extremes are where you are wanting to pay the closest attention to, particularly where the %K & %D lines cross (i.e the red and green lines). This is typically where we begin to see changes in the behavior of the market - not always but quite often enough, to warrant our attention. What this tool is best for, in terms of what I use it for, is market timing and position building. When there is a crossover at one of the extremes that goes against the positions in my portfolio, I, often times, look to take profits in those positions or at least hedge against them. I'm planning on coming out with a more formal tutorial on this in the days to come. But for now, this should do.
Here is the NYSE Reversal Indicator.