Rephrase the following caption for a figure of a scientific paper:
"The mean negative log-likelihood (NLL) versus $\alpha$ for (a) various $D$ (in colors) of
fractional Brownian motion (FBM) is proportional to the correlations' magnitude.
(b) The mean NLL for each $alpha$ and $D_0$ (same colors) of 
scaled Brownian motion (SBM) is directly related to the scale." Your response should contain 600+ words.
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