hi,
i have been working on an Options assignment, and i have this formula as one of my answers:
X_{t}=\left\{\begin{array}{cc}X_{t-1},&\mbox{if } S_{t} < S_{t-1}\\aS_{t},& \mbox{if } S_{t}\geq S_{t-1}\end{array}\right
where a is a constant. the question however asks for a "single...