Читать книгу Encyclopedia of Chart Patterns - Thomas N. Bulkowski - Страница 43

The bearish AB=CD is a Fibonacci based pattern, meaning Fibonacci ratios determine the turning points.

Figure 2.1 shows an example of a bearish AB=CD pattern. The pattern appears as turns ABCD on the chart. In this example, leg AB's height is similar to the height of CD, hence the name of the pattern. In the ideal case, you'll see leg CD equal AB. Often, however, the CD leg may be a Fibonacci extension away (meaning point D can be far away from the other three turns). That's not a flaw. Rather, that's just the way the pattern is constructed.

Figure 2.1 A bearish AB=CD pattern correctly predicts a downward move in the stock after turn D.

The duration (days) of AB should also equal the CD duration in the ideal case. Here we see leg AB lasting 6 calendar days and CD lasting 8. That's quite close, isn't it? Most of the time, like I described for price, point D's date can be far removed from the other points.

In well‐behaved patterns of this type, the slope of the AB line should be similar to the CD slope, with a retrace in between. That's almost what you see in Figure 2.1, but it's seldom that pretty. In fact, you can see some bizarre‐looking AB=CD patterns even though they qualify as valid Fibonacci patterns.

Volume trends downward in this example, shown on the chart as E.

This ABCD is a good performer. Price completes a tidy and compact‐looking pattern and then price falls, making an extended decline into December. That's how the pattern is supposed to behave.

Let's go through the guidelines for identifying these patterns.