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تسجيل مستخدم جديدBounds on the running maximum of a random walk with small drift
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We derive a lower bound for the probability that a random walk with i.i.d. increments and small negative drift $mu$ exceeds the value $x>0$ by time $N$. When the moment generating functions are bounded in an interval around the origin, this probability can be bounded below by $1-O(x|mu| log N)$. The approach is elementary and does not use strong approximation theorems.
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