when the price is choppy so are the buy and sell signals on the left side of the chart there are many zero line crossovers that did not generate profitable trade signals nor identified the trend conclusively 
on the right side of the chart there were more trending periods in the price during this period the qstick did a better job of identifying the trend staying above zero when the price trend was up and staying below zero when the price trend was down the difference between the qstick indicator and rate of change roc qstick looks at the difference between open and closing prices and then takes an average of that difference the roc indicator looks at the difference between the current closing price and a closing price n periods ago that amount is then divided by the close n periods ago and then multiplied by 100 the indicators are similar but look at slightly different data are calculated differently so they will have slightly different trade signals limitations of using the qstick indicatorthe qstick indicator only looks at historical data and takes a moving average of it therefore it is not inherently predictive and its movements will typically lag behind the actual movements in price the qstick can produce anomalies when the price is gapping in one direction but the intraday price action moves the other this may cause divergences between the price and the indicator but may not necessarily indicate a timely reversal in price the trade signals may not necessarily be ideal and often need to be combined with some other filter in choppy conditions the price will whipsaw across the zero line and or signal line generating numerous losing trades 