When to use the Diebold-Mariano forecast horizon test?
The Diebold-Mariano test included in the {forecast} package seems like an appropriate measure to test the two forecasts for statistically significant differences in prediction accuracy. However, I am unsure whether the horizon h of my predictions in this case is 1 (as I forecast 1-step-ahead for each time slot)
How is the Diebold Mariano test used in Excel?
We use the Diebold-Mariano test to determine whether forecasts are significantly different. Let ei and ri be the residuals for the two forecasts, i.e. The time series di is called the loss-differential. Clearly, the first of these formulas is related to the MSE error statistic and the second is related to the MAE error statistic.
Which is better the Diebold Mariano test or the HLN test?
Actually, the Diebold-Mariano test tends to reject the null hypothesis too often for small samples. A better test is the Harvey, Leybourne and Newbold (HLN) test, which is based on the following:
Is the time series Di called the loss differential?
The time series di is called the loss-differential. Clearly, the first of these formulas is related to the MSE error statistic and the second is related to the MAE error statistic. We now define As described in Autocorrelation Function γk is the autcovariance at lag k.
How to calculate the Diebold Mariano loss differential?
When applying the Diebold-Mariano test to test for predictive accuracy we need to specify a loss differential. For instance the loss differential d in terms of the mean absolute error (MAE) is d = a b s (e 1) − a b s (e 2) where e 1, e 2 are the errors of two competing forecasts and are nobs-by-1 matrices.
Is the DM test useful for comparing models?
Abstract: The Diebold-Mariano (DM) test was intended for comparing forecasts; it has been, and remains, useful in that regard. The DM test was not intended for comparing models. Much of the large ensuing literature, however, uses DM-type tests for comparing models, in pseudo-out-of-sample environments.
Is the DM test suitable for comparing two vectors?
The DM test is not suited for comparing 2 vectors containing forecasts made at one point in time for different forecasting horizons. What you are doing is essentially seasonal model. Your time unit is one hour. And your seasonal frequency is 24*7=168 time units (hours).