Suppose from the forex tick data collected, we resample the time series at regular intervals. The average of prices over a reasonably short time period and long time period are calculated. The beta of the price series is taken as the ratio of the short-term average prices to the long-term average prices. In price series, where there is no trend, the ratio is 1—short-term prices are equal to the long-term prices. When prices are on an uptrend, the short-term prices are higher than the long-term average price levels and the beta is more than 1. Conversely, when prices are on a downtrend, the beta is less than 1.

In this section, we will discuss the implementation of a trend-following trading system to buy a position when prices are in an uptrend and sell when prices are going downtrend.