"Indicator rises"
For long positions: - sends a signal every time when the current indicator value is higher than the previous value.
For short positions: - sends a signal every time when the current indicator value is lower than the previous value.
"Indicator falls"
For long positions: - sends a signal every time when the current indicator value is lower than the previous value.
For short positions: - sends a signal every time when the current indicator value is higher than the previous value.
"Indicator changes its direction upward"
For long positions: - sends a signal when the current indicator value is higher than the previous value and the previous value was lower than the value before the previous value.
For short positions: - sends a signal when the current indicator value is lower than the previous value and the previous value was higher than the value before the previous value.
There must be at least 0.000001 difference between the values in order to detect rise, fall, change direction.
The AO indicator changes in a very narrow range because both MAs has very small difference of their periods.
If you change the periods to 15 and 25, you'll see the difference more clear.
![http://s13.postimg.org/63yrlwooz/2015_11_11_10_07_37.jpg](http://s13.postimg.org/63yrlwooz/2015_11_11_10_07_37.jpg)