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In RER, equally strided transitions are sampled from the latest

transition. The next sample contains one step older transions.

\[ \begin{align}

B_1 &= \lbrace& T_{t}  &, T_{t-stride}  &, \dots &, T_{t-batch~size \times stride}     &\rbrace \\

B_2 &= \lbrace& T_{t-1}&, T_{t-stride-1}&, \dots &, T_{t-batch~size \times stride - 1} &\rbrace \\

&\vdots&&&&&&

\end{align} \]

\[ \begin{align} B_1 &= \lbrace& T_{t}  &, T_{t-stride}  &, \dots &, T_{t-batch~size \times stride}  &\rbrace \\ B_2 &= \lbrace& T_{t-1}&, T_{t-stride-1}&, \dots &, T_{t-batch~size \times stride - 1} &\rbrace \\ &\vdots & & & & & & \end{align} \]

When the first sample index ($t-i$) becomes $2 \times stride$ old from

the latest transition, the first sample index is reset to the latest