Derivatives

  • Using GARCH to Forecast Volatility

    🎯 GARCH is not just a descriptive model — its purpose is to forecast the volatility of future returns on invested capital. In previous posts, we: Now we answer the key question: How do we use the model once we are confident it works properly? 🔧 Forecasting Mechanism The original model is defined as:σt+12=ω+αut2+βσt2sigma_{t+1}^2 =…

    Read more →

  • Validation of Volatility Clustering

    Models of return volatility such as EWMA and GARCH aim to explain volatility clustering. In real markets, calm periods tend to be followed by calm periods, while turbulent periods are followed by turbulent periods. The better a model explains this clustering, the higher its quality. For example, the quality of a GARCH model can be…

    Read more →

  • Maximum Likelihood Method

    The maximum likelihood method is used in modeling to estimate the parameters that make historical events most probable. Suppose an event has occurred. If we assume that this event happened according to probabilistic expectations, then we need to determine what that probability is. MLE = choose parameters that maximize probability of observed data A simple…

    Read more →

  • GARCH Model

    GARCH (1,1) and Volatility Clustering Financial markets exhibit an important property: volatility clustering and reversion toward a long-run average. In other words, large movements tend to be followed by large movements, and calm periods tend to be followed by calm periods. However, over time volatility tends to move back toward a long-term average level. To…

    Read more →

  • Volatility is such an overused term that we may forget how important the assumptions are that lead to the final number. Let us start with the basics. When we talk about volatility, we mean the volatility of returns, not the volatility of the asset price itself. Next, volatility changes over time, so we need to…

    Read more →

  • VaR – Advanced Issues

    VaR – Advanced Issues

    In previous posts, I covered the calculation of portfolio Value at Risk (VaR) and Expected Shortfall using the historical simulation and linear modeling methods. Now, in order to close the topic, I will briefly touch on several additional interesting aspects. Bond Portfolio – Interest Rate Risk In the previous notes, VaR calculations referred to an…

    Read more →

  • VaR – Linear Model

    VaR – Linear Model

    In the previous note about VaR, I discussed and showed how it is calculated using simulation of historical data. Now I will demonstrate how it is calculated using linear modeling. First, we again construct the statistics of historical data; Then we calculate returns obtained from price changes — LN (t1/t0); After that, we build the…

    Read more →