Semi Variance

Semi variance is a risk measure that focuses exclusively on the downside volatility of an asset. Unlike standard variance, which treats both gains and losses as equally risky deviations from the mean, semi variance only considers observations that fall below a specific target or mean return.

In cryptocurrency and derivatives trading, this is particularly useful because traders are generally concerned with the risk of loss rather than the volatility of upside gains. By ignoring positive returns, semi variance provides a more accurate picture of the true risk of drawdown.

It helps portfolio managers and quantitative traders isolate the probability and magnitude of negative outcomes. This metric is essential for building robust risk management frameworks in highly volatile markets.

It is a core component of the Sortino Ratio, which adjusts returns based on downside risk. Understanding semi variance allows for better capital allocation by identifying assets that exhibit frequent small losses versus those with rare but catastrophic tail risks.

It is a critical tool for assessing the safety of decentralized finance protocols and leveraged derivative positions.