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Specification:

Using expressions [*] and [*] we can directly construct
\begin{displaymath}
\ell^{\pm_{(k,P)}}(c) =
{\sum_{t\in\Phi^{\pm_{(k,P)}}(c)}{\cal L}_{t-1}^{_{(k,P)}}.
\over{\char93 }(\Phi^{\pm_{(k,P)}}(c))}\end{displaymath} (37)
which is the mean log-likelihood of all loss exceedences over confidence level c for a long (+) or short (-) position in the US Dollar with respect to the series k or portfolio P.

Finally, as specified by expressions [*] and [*], we construct the univariate average mean log-likelihood
\begin{displaymath}
\ell_u(c) = {1\over20}\left(\sum_{k=1}^{10}\ell^{+_{(k)}}(c) +
\sum_{k=1}^{10}\ell^{-_{(k)}}(c)\right)\end{displaymath} (38)
and the multivariate average mean log-likelihood
\begin{displaymath}
\ell_m(c) = {1\over2}\left(\ell^{+_{(P)}}(c) + \ell^{-_{(P)}}(c)\right)\end{displaymath} (39)
plotted in figures 4u and 4m respectively for all candidate models. Plots are always for the confidence range of $50\%$ and higher, since this defines the division between loss making and profitable events. Due to symmetrization (consideration of both long and short, positions) the value of $\ell_u(c = 50)$ is based on all 10000 out-of-sample events xt(k) $(t\in[2,1001])$ and the value $\ell_m(c = 50)$ is based on all 1000 out-of-sample events xt(P) $t\in[2,1001]$$(t\in[2,1001])$ .