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Consider the problem of allocating indivisible goods among agents with additive valuations, where monetary payments are not allowed. When randomization is allowed, it is possible to achieve compelling notions of fairness such as EV, which states that no agent should prefer any other agent's allocation to their own. When allocations must be deterministic, achieving exact fairness is impossible but approximate notions such as EV up to one good can be guaranteed. In "Best of Both Worlds: Ex Ante and Ex Post Fairness in Resource Allocation," H. Aziz, R. Freeman, N. Shah, and R. Vaish ask whether it is possible to achieve both types of guarantees simultaneously. More specifically, they ask whether there exists a probability distribution over deterministic allocations such that every deterministic allocation is envy-free up to one good and the distribution is exactly envy-free in expectation. The main result of the paper answers this question in the affirmative, showing that ex ante and ex post fairness need not be in conflict. We study the problem of allocating indivisible goods among agents with additive valuations. When randomization is allowed, it is possible to achieve compelling notions of fairness such as envy-freeness, which states that no agent should prefer any other agent's allocation to their own. When allocations must be deterministic, achieving exact fairness is impossible but approximate notions such as envy-freeness up to one good can be guaranteed. Our goal in this work is to achieve both simultaneously, by constructing a randomized allocation that is exactly fair ex ante (before the randomness is realized) and approximately fair ex post (after the randomness is realized). The key question we address is whether ex ante envy-freeness can be achieved in combination with ex post envy-freeness up to one good. We settle this positively by designing an efficient algorithm that achieves both properties simultaneously. The algorithm can be viewed as a desirable way to instantiate a lottery for the probabilistic serial rule. If we additionally require economic efficiency, we obtain three impossibility results that show that ex post or ex ante Pareto optimality is impossible to achieve in conjunction with combinations of fairness properties. Hence, we slightly relax our ex post fairness guarantees and present a different algorithm that can be viewed as a fair way to instantiate a lottery for the maximum Nash welfare allocation rule. Funding: This work was supported by the Office of Naval Research [Grant N00014-17-1-2621] and DST INSPIRE [Grant DST/INSPIRE/04/2020/000107]. [ABSTRACT FROM AUTHOR]

Majority of Indian hospitals still lack the provision of acute postoperative pain relief service. In other parts of the world, field of acute pain management strategy has witnessed a surge in its implementation. Today, acute pain has begun to be recognized not merely as a distressing symptom but also as a precursor of chronic, debilitating pain. This development warrants that we in India address this issue on an urgent basis through the use of analgesic/narcotic combination via parenteral/oral/rectal route as well as by performing regional blocks, to meet the interpatient variability and available facility. In this review article, we have provided the organization and function of acute pain service (APS) program that can be adapted to a wide spectrum of Indian hospitals. We have outlined the role of APS team including the use of easily available analgesic/narcotic drug combinations for various categories of Indian hospitals dealing with different grades of surgical conditions, including those hospitals that are not sufficient in resources and funding. This article has also tabulated possible regional block techniques with their indications for treating acute postoperative pain in combination with parenteral/oral/rectal analgesics/narcotics in the more developed Indian hospitals. Staffing and equipment requirements have also been outlined.

We study a two-sided matching problem under preferences, where the agents have independent pairwise comparisons on their possible partners and these preferences may be uncertain. Preferences may be intransitive and agents may even have cycles in their preferences; e.g. an agent a may prefer b to c , c to d , and d to b , all with probability one. If an instance has such a cycle, then there may not exist any matching that is stable with positive probability. We focus on the computational problems of checking the existence of possibly and certainly stable matchings, i.e., matchings whose probability of being stable is positive or one, respectively. We show that finding possibly stable matchings is NP-hard, even if only one side can have cyclic preferences. On the other hand we show that the problem of finding a certainly stable matching is polynomial-time solvable if only one side can have cyclic preferences and the other side has transitive preferences, but that this problem becomes NP-hard when both sides can have cyclic preferences. [ABSTRACT FROM AUTHOR]