Competitive Ratio
A performance measure in online algorithm analysis, defined as the maximum over input sequences of the ratio between the cost of the online algorithm and the cost of the optimal offline algorithm on the worst-case input sequence.
Timeline (last 90 days)
Under the assumption that the input order is uniformly random, the competitive ratio of the classic strategy for the secretary problem (first rejecting the first n/e candidates, then selecting the first applicant better than all previous candidates) is approximately 1/e≈0.368, that is, the best candidate can be selected with a probability of at least 37%, and this ratio is optimal.
The competitive ratio is defined as the maximum, over worst-case input sequences, of the ratio of the online algorithm's cost to the optimal offline algorithm's cost.
The known tight upper and lower bounds for the paging problem are far from the low cache miss rates of real laptops.
All Facts (3)
Under the assumption that the input order is uniformly random, the competitive ratio of the classic strategy for the secretary problem (first rejecting the first n/e candidates, then selecting the first applicant better than all previous candidates) is approximately 1/e≈0.368, that is, the best candidate can be selected with a probability of at least 37%, and this ratio is optimal.
50%UnverifiedThe competitive ratio is defined as the maximum, over worst-case input sequences, of the ratio of the online algorithm's cost to the optimal offline algorithm's cost.
50%UnverifiedThe known tight upper and lower bounds for the paging problem are far from the low cache miss rates of real laptops.
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