Useless ritual?

Useless Disinfection

A useless raffle.

A mailed questionnaire was sent to 2712 subjects asking about respiratory symptoms, and a raffle for three prizes of 50 pounds, 30 pounds, and 20 pounds was organised. The response rate in the 1762 who were told about the raffle was no higher than for 950 subjects who served as controls.

Stop Reading (Useless Parts)!

Information overload is one of the biggest problems currently omnipresent in the word largest network, the Internet. No general solution exists therefore it is important to handle this problem at least in certain areas. Large collections of articles are available to the users of the Internet. Since technology is very easy to handle for information providers, literally every person who has acces...

Parity is Positively Useless

We give the first examples of non-trivially positively-useless predicates subject only to P 6= NP. In particular, for every constraint function Q : {−1, 1}4 → R, we construct Contraint-SatisfactionProblem (CSP) instances without negations which have value at least 1 − ε when evaluted for the arity-four odd-parity predicate, yet it is NP-hard to find a solution with value significantly better th...

Useless-Variable Elimination

1 Intro In my 1988 SIGPLAN paper “Control-Flow Analysis in Scheme,” I promised to cover several items in more detail in a “forthcoming tech report.” The tech report has yet to happen. Most of the promised items have been covered in other papers (“The Semantics of Scheme Control-Flow Analysis” and “Data-Flow Analysis and Type Recovery in Scheme”). Useless-variable elimination, however, is still ...