This script contains McClellan Summation Index(MSI) and McClellan Oscillator(MO)
(1) What is McClellan Summation Index(MSI) McClellan Summation Index(MSI) is a breadth indicator derived the McClellan Oscillator(MO), which is a breadth indicator based on Net Advances (advancing issues less declining issues). The Summation Index is simply a running total of the McClellan Oscillator values. To identify the market direction, I prefer to use the relative strength(RSI) of MSI rather than MSI itself because MSI is a summation so it's difficult to compare with previous market patterns. So I use RSI applied MSI. Reference: Stockcharts.com has a nice set of detailed explanation about MSI. school.stockcharts.com/doku.php?id=market_indicators:mcclellan_summation (2) How to use this script - Add this script to your chart. - You can choose one of two options ("MSI RSI" or "MO"). - You can also choose the market from three options ("Nasdaq", "NYSE", "Nasdaq+NYSE") (3) "MSI RSI" or "MO" a) "MSI RSI" For swing trade(sevelal weeks), MSI RSI is much better to identify the broad market direction. I backtested last several years of S&P500. The result was not symmetrical between MT bear/bull market. For bull side, when MSI RSI curls up from the bottom(e.g. RSI 30 level), 90% of times out of them the market rallied. For bear side, when MSI RSI rolles over to downside from the top(e.g. RSI 70 level), only 60% of times out of them the market declined. So the market tends to hit negatively diverrgent high from advancing/declining issues perspective. Be careful to use MSI oscilator. b) "MO" For short term trade(intraday, 2-3 days of holding), MO is better because MSI is a summation so lags several days. MO is quick. MO is sometimes very noisy, so you need to draw trendlines or horizontal levels to compare with the previous cases. For beginners, I recommend to use "MSI RSI".