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Incidence of gallstones in those aged ≥ 80 years is as high as 38%-53%. The decision-making process to select those oldest old patients who could benefit from cholecystectomy is challenging.To assess the risk of morbidity of the "oldest-old" patients treated with cholecystectomy in order to provide useful data that could help surgeons in the decision-making process leading to surgery in this population.A retrospective study was conducted between 2010 and 2019. Perioperative variables were collected and compared between patients who had postoperative complications. A model was created and tested to predict severe postoperative morbidity.The 269 patients were included in the study (193 complicated). The 9.7% of complications were grade 3 or 4 according to the Clavien-Dindo classification. Bilirubin levels were lower in patients who did not have any postoperative complications. American Society of Anesthesiologists scale 4 patients, performing a choledocholithotomy and bilirubin levels were associated with Clavien-Dindo2 complications (Patients with American Society of Anesthesiologists scale 4, higher level of bilirubin and need of choledocholithotomy are at the highest risk of a severely complicated postoperative course. Alternative endoscopic or percutaneous treatments should be considered in this subgroup of octogenarians.

Recent work on optimal monetary and fiscal policy in New Keynesian models has tended to focus on policy set by an infinitely lived benevolent policy maker, often with access to a commitment technology. In this paper, we explore deviations from this ideal, by allowing (time-consistent) policy to be set by a process of bargaining between two political players with different weights on elements of the social welfare function. We characterize the (linear) Markov perfect equilibrium and, in a series of numerical examples, we explore the resultant policy response to shocks which cannot be perfectly offset with the available instruments due to their fiscal consequences. We find that, even although the players, on average, have the socially desirable objective function, the process of bargaining implies an outcome which deviates from the time-consistent policy chosen by the benevolent policy maker. Moreover, the range of instruments available mean that policy makers will bargain across the entire policy mix, sometimes implying outcomes which are quite different from those that would be chosen by a single policy maker. These policy outcomes depend crucially on the nature of the conflict and also the level of government debt.

Many negotiations (for instance, among political parties or partners in a business) are characterized by dynamic bargaining: current agreements affect future bargaining possibilities. We study such situations using bargaining games á la Rubinstein (Econometrica 50:97–109, 1982), with the novelty that players can decide how much to invest, as well as how to share the residual surplus for their own consumption. Their investment decisions affect the size of the next surplus. In line with the existing literature, we focus on Markov Perfect Equilibria, where consumption and investment are linear time-invariant functions of capital and show that standard results in bargaining theory can be overturned. For instance, a more patient proposer may consume less than his opponent. The intuition is that when capital is productive, both parties have incentives to invest, however, the most patient party wishes to invest significantly more than his opponent. Then, to prioritize investment—which affects future bargaining possibilities—the former must make larger concessions and let the latter consume more. Another interesting result is that if a player becomes more patient, both parties may reduce their investment. The key underlying driver of this result is that when counteroffers become cheaper for an impatient party, he is able to reduce his investment and consume more. This forces his opponent to make larger concessions (and reduce his investment plan). Moreover, extreme demands (where a player consumes all the residual surplus) are possible in equilibrium, under fairly modest assumptions. Finally, only when bargaining is frictionless, is the equilibrium efficient.

We study a bargaining game (a la Rubinstein) in which parties are allowed to invest part of an available surplus. Therefore, in addition to the standard problem of how to divide a surplus for their own consumption, parties face the additional problem of how much to invest, knowing that the level of investment affects the surplus available in the next period. We provide an algorithm to solve the game when the number of bargaining stages is finite but tends to infinity.We show that the equilibrium investment and consumption shares become independent of the capital stock. The convergence of the equilibrium demands is affected by the elasticity of substitution and parties’ patience.

TMany negotiations are characterised by dynamic accumulation: current agreements affect future bargaining possibilities. We study such situations by using repeated bargaining games in which two parties can decide how much to invest and how to share the residual surplus for their own consumption. We show that there is a unique (stationary) Markov Perfect Equilibrium characterised by immediate agreement. Moreover, in equilibrium a relatively more patient party invests more than his opponent. However, being more patient can make a player worse off. In addition, we derive the conditions under which we obtain an efficient investment path. Our results are robust to different bargaining procedures, different rates of time preference and elasticities of substitution.

In many bargaining situations the decisions that parties take at one point in time affect their future bargaining opportunities. We consider an ultimatum bargaining game in which parties can decide not only how to share a current surplus but also how much to invest in order to generate future surpluses. We show that there is a unique Markov perfect equilibrium (MPE) in which a proposer consumes the whole surplus not invested. Moreover, when the proposer has a sufficiently high discount factor, his MPE investment level is higher than his opponent’s, for a given capital stock. Finally, we show that bargaining can lead to overinvestment.

The focus of this paper is on repeated bargaining games in which two parties can decide how much to invest and how to share the remaining surplus for their own consumption. The game is dynamic since the current level of investment affects future surpluses. We characterise an MPE without delays in general terms and show the parametrical effects for the specific case in which parties share the surplus equally. We show that the relatively more patient player invests more than his opponent, for a given capital stock. Moreover, if the probability of becoming a proposer decreases for the more patient player, then such a player reduces his investment, while the relatively impatient player increases his investment.

The focus of the paper is on issue-by-issue bargaining procedures in which parties are allowed to differ not only in their valuations of the issues but also in their rates of time-preference. We show that the interplay of the forces in the bargaining game is complex and standard assumptions in the literature, such as a common discount factor, can be strong. We investigate the SPE of the game when the order of the issues can be changed and show that parties can have the same preferences over agendas when they both agree over the importance of an issue or when they disagree (if corner solutions are allowed and/or there is a difficult/urgent issue).

We study the effects of a between-cake discount factor in the agenda selection problem faced by a multi-issue committee. The presence of an interval of time between bargaining stages is a reasonable and realistic assumption. We show that this assumption simplifies the agenda selection problem strongly. In particular, the equilibrium multiplicity obtained in In and Serrano (2002) does not hold: a unique SPE can be established among the sequential bargaining procedures.