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Background Anaesthetic induction occurs at higher plasma drug concentrations than emergence in animal studies. Some studies find evidence for such anaesthetic hysteresis in humans, whereas others do not. Traditional thinking attributes hysteresis to drug equilibration between plasma and the effect site. Indeed, a key difference between human studies showing anaesthetic hysteresis and those that do not is in how effect-site equilibration was modelled. However, the effect-site is a theoretical compartment in which drug concentration cannot be measured experimentally. Thus, it is not clear whether drug equilibration models with experimentally intractable compartments are sufficiently constrained to unequivocally establish evidence for the presence or absence of anaesthetic hysteresis. Methods We constructed several models. One lacked hysteresis beyond effect-site equilibration. In another, neuronal dynamics contributed to hysteresis. We attempted to distinguish between these two systems using drug equilibration models. Results Our modelling studies showed that one can always construct an effect-site equilibration model such that hysteresis collapses. So long as the concentration in the effect-site cannot be measured directly, the correct effect-site equilibration model and the one that erroneously collapses hysteresis are experimentally indistinguishable. We also found that hysteresis can naturally arise even in a simple network of neurones independently of drug equilibration. Conclusions Effect-site equilibration models can readily collapse hysteresis. However, this does not imply that hysteresis is solely attributable to the kinetics of drug equilibration.

BACKGROUND: Anaesthetic induction occurs at higher plasma drug concentrations than emergence in animal studies. Some studies find evidence for such anaesthetic hysteresis in humans, whereas others do not. Traditional thinking attributes hysteresis to drug equilibration between plasma and the effect site. Indeed, a key difference between human studies showing anaesthetic hysteresis and those that do not is in how effect-site equilibration was modelled. However, the effect-site is a theoretical compartment in which drug concentration cannot be measured experimentally. Thus, it is not clear whether drug equilibration models with experimentally intractable compartments are sufficiently constrained to unequivocally establish evidence for the presence or absence of anaesthetic hysteresis. METHODS: We constructed several models. One lacked hysteresis beyond effect-site equilibration. In another, neuronal dynamics contributed to hysteresis. We attempted to distinguish between these two systems using drug equilibration models. RESULTS: Our modelling studies showed that one can always construct an effect-site equilibration model such that hysteresis collapses. So long as the concentration in the effect-site cannot be measured directly, the correct effect-site equilibration model and the one that erroneously collapses hysteresis are experimentally indistinguishable. We also found that hysteresis can naturally arise even in a simple network of neurones independently of drug equilibration. CONCLUSIONS: Effect-site equilibration models can readily collapse hysteresis. However, this does not imply that hysteresis is solely attributable to the kinetics of drug equilibration.

Industrial structure can describe not only the structural relationships between industrial output capacities, but also the structural relationships between industrial economic outputs. Fixed-asset investment affects industrial structure through the formation of capital stock and contemporaneous demand. Based on VAR model, this paper utilizes Granger causality test and other econometric methods to analyze the hysteresis relationships between fixed-asset investment and industrial structure in China from 1991 to 2017. In addition, the contemporaneous relationships are identified by employing the Directed Acyclic Graph (DAG) analysis. The results show that: The hysteresis relationships exist in primary and secondary industries between fixed-asset investment and their respective value added. The fixed-asset investment in primary and tertiary industries are the contemporaneous causes of positive effect to the value added of primary industry. And the value added of secondary industry is the contemporaneous cause of positive effect to its fixed-asset investment.

As the “Volcker shock” is believed to have generated useful information on the effects of monetary policy, this paper develops a transparent procedure to identify other significant monetary contractions. The approach is applied to a panel data set spanning 162 countries (over the period 1970-2017), in which it identifies 147 large monetary contractions. The procedure selects episodes where a protracted period of loose monetary policy was suddenly followed by sizeable interest rate increases. Focusing on contractions of significant size increases the signal-to-noise ratio, while they are unlikely to be accompanied by confounding “information effects” (markets interpreting a rate hike as the Central Bank being optimistic about the real side of the economy). A subsequent panel VAR analysis suggests that, on average, a 100-basis point rate hike reduces real GDP by 0.5 percent. This reduction in output seems to be persistent, pointing to a certain degree of hysteresis. The price level falls by 1.5 percent, indicating that the medium-/long-run impact of contractionary monetary shocks is not characterized by a neo-Fisherian response. Advanced economies appear to display more price stickiness than emerging/developing countries, as the former combine a more muted price response with a larger effect on output.

Hysteresis nonlinearity is a common phenomenon in mechanical actuators. Specially, it appears when the direction of motion of mechanical actuated joint is reversed in robotic manipulator. This paper focuses on the force feedback control problem for bilateral teleoperation system with unknown Prandtl-Ishlinskii (PI) hysteresis. First, an improved sliding mode observer with adaptive gains is provided for estimating the external force signals acting on the manipulators. This removes the need for force sensors and reduces hardware-cost. Next, to improve transparency and guarantee the passivity of the communication network, a four-channel wave variable transformation scheme including force information is introduced. Then, an adaptive switching-based control framework is proposed to deal with Prandtl-Ishlinskii hysteresis dynamics. Finally, the theoretical findings are supported by simulation and experiment results.

This study presents a dynamic Kaleckian model with different demand and distribution regimes, a monetary policy rule and hysteresis in the natural output level. We analyse the local stability of the steady state and the transitional dynamics in different combinations of demand and distribution regimes. Our model indicates that the initial condition in an economy matters for the steady state selection from multiple ones. Using impulse response function analysis, we show that a temporary shock to the income distribution can cause permanent effects on the dynamics of endogenous variables. Moreover, the degree of hysteresis influences the magnitude of impact on output levels. Monetary policy cannot stabilise output levels in the face of temporary shocks. Finally, we find that in a wage-led demand regime, a rise in inequality of functional income may lead to secular stagnation.

In this paper, a global decentralized adaptive output feedback control is proposed for a class of nonlinear interconnected time delay systems, in which each subsystem covers unknown parameters, the unmeasured states dependent nonlinearities, and unknown saturated PI hysteresis. By constructing modified dynamic high-gain observers, together with backstepping technique, the unmeasured states dependent nonlinearities that fail to match global Lipschitz condition can be well disposed and global stability of the overall closed-loop system is obtained. With the aid of a new adaptive law, the restrictive assumption requiring known bounds of the time-varying delays in the existing literature is removed. Furthermore, based on the prescribed performance technique, it can be proved that both steady state and prespecified transient tracking performance are able to be guaranteed.

This paper investigates the persistence of the unemployment rate for the UK and the US over the past century by modeling the persistence to randomly evolve over time. The estimated autoregressive coefficient exhibits significant variation over time indicating the fluctuation between the hysteresis and mean-reverting phases. We find that the hysteresis phase is, to a considerable extent, associated with economic downturns caused by macroeconomic shocks, with the unemployment rate during this phase showing large deviations from the estimated natural rate of unemployment. In contrast, for the periods conforming to the natural rate theory, the actual unemployment rate fluctuates relatively closely around the estimated natural rate of unemployment.

Indigenous peoples and local communities (IPLC) often use natural resources as both a reason and mechanism for environmental management, yet a number of environmental, social, and economic drivers disrupt this relationship. Here, we argue that these drivers can also trigger a set of feedback mechanisms that further diminish the efficacy of local management. We call this process biocultural hysteresis. These feedbacks, which include knowledge loss and a breakdown of social hierarchies, prevent IPLC from adapting their management to change. Biocultural hysteresis worsens as IPLC spend an increasing amount of time outside their social-ecological context. Therefore, we argue for adaptive policies and processes that favour protecting and enabling IPLC engagement with their environment.

Positive slopes in the performance characteristics of pump-turbines are an indicative feature of unstable behaviour in pump mode operation, and are additionally conducive to instability problems during pump start-up. With the rapid development of pumped-storage power plants, this instability has become increasingly critical to the safe and stable operation of the entire unit. Thus, this topic has been attracting attention in the pump-turbine design and research fields. In this study, the relative achievements with regard to positive slopes, which have been obtained by various investigators over the last two decades, were reviewed. Such studies, including flow characteristics, and influence parameter, related to positive slopes were summarized. The generating mechanism, accompanying unsteady phenomena, and corresponding hysteresis phenomena, are also discussed. Investigations on the influence of geometric and operating unit parameters are presented. Finally, precautions and countermeasures for the improvement of positive slopes, and various perspectives regarding future work are proposed. The present review provides theoretical guidance for the design and operation of pump-turbines, in terms of the stability of the pumped-storage powers plants.

We investigate a behavioral epidemic model including a partially effective vaccination at all ages. The vaccination is information-dependent, in the sense that the vaccination rate of susceptibles depends on the current and the past information available about the disease prevalence in the population. The weight given to the past history is described by an exponential kernel. The proposed model presents both the possibility of backward bifurcation and that of oscillations triggered by behavioral memory. Furthermore, a forward hysteresis scenario may take place where multiple endemic states are possible when the basic reproduction number P 0 is greater than one. Finally, a stable endemic state may destabilize via Hopf bifurcation not only when P 0 > 1 but also when P 0 1 , depending on the interplay between some relevant information-related parameters.

This paper is concerned with a control system modeling concrete carbonation process when underlying hysteresis effects are taken into account. The system consists of a diffusion equation for moisture and an ordinary differential equation accounting for the hysteresis. We obtain the bang–bang principle for this system asserting the proximity of all attainable states to the so-called bang–bang states. The later are the states reached by controls valued in the extreme points of the control constraint. In our study we are able to dispense with the monotonicity of the right-hand side in the hysteresis equation. This assumption has repeatedly appeared in previous analysis of control systems with hysteresis.

We study the distributive effects of a negative shock to banks assets in a saver-capitalist model. We analyze how this kind of heterogeneity affects macroeconomic variables and the distribution between savers and capitalists through banks leverage procyclicality. The distributive effects are non-favourable to savers and long lasting. Lower risk aversion of capitalists strengthens and lengthens the procyclicality of leverage, leading to a lower decrease of savers’ income and consumption. Whilst stricter regulatory requirements are favourable to savers, a tougher inflation targeting is unfavourable to savers. The model is robust to the combined introduction of labour market frictions and hysteresis, which together generate an amplification and lengthening of the recessionary and distributive effects unfavourable to savers.

Observations from empirical data in the roadway network showed that the relation between averages of network flow versus density often exhibit hysteresis and bifurcation phenomena, which may obscure the reproducibility of a well-defined macroscopic fundamental diagram (MFD). In this paper, we analyzed large-scale trip data from passenger vehicles in an urban network of South Korea and evaluated the shapes of MFDs over many days. It was found that MFDs have two distinctive, reproducible forms: a well-defined, unique relation on weekends and a bifurcation in high-density regime on weekdays. With regard to the bifurcation, we observed higher network flows in the morning and lower network flows in the evening for the same average network density. This implies that the same set of drivers in the network collectively formed two different trip patterns. Hence, we evaluated possible factors that may have effects on the bifurcation phenomenon. In view of this, four factors – heterogeneity, trip completion rate, detouring ratio and commute trips – were analyzed in this study. The findings showed that travelers’ detours could be a key factor for the occurrence of bifurcation because, by detouring travelers improve neither their own travel times nor network-wide travel times, and thereby degrade the network production.

Whether long memory effect plays an important role in car-following models remains unsolved. In this paper, we study the possible relationship between long memory effect and hysteresis phenomena observed in practice. Especially, we have compared the performance of different deep learning based car-following models that take various time-scale historical information as inputs. Test show that hysteresis phenomena can be correctly simulated only by car-following models with long memory. So, we argue that car-following models should embed long memory effect appropriately.

This paper analyzes unemployment rates in the euro area (EA) countries to test for EA-related benefits and economic integration of the EA in the form of lower unemployment rates and unemployment rates convergence. We employ recently developed unit root tests with structural breaks and non-normal errors to analyze the persistence, test the stochastic convergence and locate structural break(s) in EA unemployment rates from 1995q1 to 2016q2. Our results imply a certain degree of unemployment hysteresis in the EA. Even though the results support the stochastic convergence of the majority of EA countries, we find that EA membership is not a sufficient condition for stochastic convergence. Nevertheless, EA-related breaks are followed by the periods of convergence to the EA11 average. Crisis-related breaks are followed by the periods of divergence. Although providing initial benefits, EA is not functioning as an optimal currency area.

Using monthly data of 79 Russian regions from 2003 to 2017, we study the long-run relationship of the retail gasoline prices with the crude oil price and the nominal exchange rate. We find that models that were successfully applied to deal with asymmetries in other countries are not suitable for Russia without taking structural breaks into account. Once breaks are allowed, we find that there is no asymmetry in the long-run elasticities between the gasoline prices and the crude oil price, and no significant hysteresis. However, there is an asymmetric relation between the gasoline price and the exchange rate that has decreased over time. These results also hold after several robustness checks. The evidence reported in this work shows that the effects of the exchange rate on gasoline prices are much more difficult to control than the oil price, and they require a larger set of policy measures: the recent development of a plan to decrease the importance of hydrocarbons exports by producing clean hydrogen using electrolysis and pyrolysis and the potential future export of electricity generated using nuclear power and onshore wind farms may help to diversify the local economy and to shield it from new sanctions.

Hysteresis is treated as a history dependent branching, and the use of the classical Preisach model for the analysis of macroeconomic hysteresis is first discussed. Then, a new Preisach-type model is introduced as a macroeconomic aggregation of more realistic microeconomic hysteresis than in the case of the classical Preisach model. It is demonstrated that this model is endowed with a more general mechanism of branching and may account for the continuous evolution of the economy and its effect on hysteresis. Furthermore, it is shown that the sluggishness of economic recovery is an intrinsic manifestation of hysteresis branching.

This paper investigates unemployment persistence in the 27 EU member states by applying fractional integration methods to quarterly data (both seasonally adjusted and unadjusted) from 2000q1 to 2020q4. The obtained evidence points to high levels of persistence in all cases. With seasonally adjusted data, a small degree of mean reversion is found in the case of Belgium, Luxembourg and Malta, but this evidence disappears under the assumption of weakly correlated disturbances. More cases of mean reversion are found instead when analysing the unadjusted series. In particular, countries such as Belgium, France, Croatia, Italy, Luxembourg and Malta display orders of integration significantly lower than 1. In addition, significant negative time trends are found in the case of Bulgaria, Croatia, Malta and Romania, and a positive one for Luxembourg. Finally, the Covid-19 pandemic had mixed effects, with (seasonal) persistence increasing in some countries whilst decreasing in others and not changing in a minority of cases. On the whole, our results support the hysteresis hypothesis for the European economies., Luis A. Gil-Alana is also grateful for financial support from the MINEIC-AEI-FEDER PID2020-113691RB-I00 project from ‘Ministerio de Economía, Industria y Competitividad’ (MINEIC), `Agencia Estatal de Investigaci on' (AEI) Spain and `Fondo Europeo de Desarrollo Regional' (FEDER), and from an internal project of the Universidad Francisco de Vitoria.

The COVID-19 pandemic has accelerated the digitalisation of the global economy and industry. However, the Next Generation EU (NG-EU) plan, which aims to provide a strong economic recovery for EU member states, has been criticised for its allocation delay and increased risk of hysteresis, that is, the dependence of the state of a system on its history. Under these circumstances, this paper proposes a blockchain-based two-layer system, Next Generation Digital Currency (NGDC), to assist an accountable and transparent fund allocation process for NG-EU funds. A consortium network in layer one is designed for all EU member state central banks and the European Central Bank (ECB) to maintain a trustable and verifiable fund tracking ledger. A Prime-Coordinator PBFT (PC-PBFT) consensus mechanism-based agreement protocol is proposed to resolve discrepancies in the transaction validation process. The simulation results show that PC-PBFT can support at least 30 transactions per second (tps) with transaction processing time less than 1 second on average.

There is a substantial literature on the lasting damage to economic output from financial crises. The COVID crisis is not, in the first instance, a financial crisis and nor was the eve of the pandemic characterised by large scale macroeconomic imbalances. But it is not financial crises qua financial crises that cause long term damage, but a number of channels which operate during financial crises and other recessions, some of which are at work now as well. We identify balance sheet repair, belief scarring, labour market hysteresis, slowing structural reform momentum, and policy error as relevant transmissions channels of long term damage at work during this crisis. Our judgement is that the COVID crisis will impart a permanent levels shock to post-pandemic global economic output of 3% of GDP. This is a third the levels damage after the GFC, consistent with the nature of the shock and the more encouraging monetary, fiscal and structural policy responses. But this is still a substantial amount of long-term damage relative to 'typical' downturns, reflecting the depth of the pandemic shock and the channels of damage identified.

We analyze the effects of government spending in a New-Keynesian model with search and matching frictions featuring endogenous growth through learning-by-doing and skill loss from long-term unemployment. We show that medium-run and long-run output and unemployment multipliers are much larger compared to the standard model that abstracts from endogenous growth and skill loss.In our model the aggregate effect of a temporary fiscal stimulus is amplified via the skill loss channel through lower training costs. Via the learning-by-doing channel, it leads to hysteresis in human capital accumulation and thereby output. These results hold for alternative forms of fiscal financing (lump-sum tax, distortionary tax and government debt) as well as alternative labor market institutions (US and Europe).

The Supreme Court’s 2006 decision in eBay v. MercExchange seemingly heralded a major change in not only patent law but also copyright law. The Court ruled that injunctions for patent infringement should no longer be granted automatically; instead, plaintiffs must establish the need for injunctive relief in particular and that such relief would be in the public interest. Although eBay concerned a patent claim, its reasoning relied on three copyright decisions, making its application to copyright cases compelling. Nevertheless, lower courts in some early post-eBay copyright cases rebuffed arguments that the Court’s ruling affected grants of injunctive relief. A 2012 empirical study of the first four years of post-eBay copyright cases seemed to show that those early cases were not aberrations, reporting that courts rarely cited eBay and continued to grant injunctions in a high percentage of copyright cases. Those conclusions were broadly accepted by the field. This Article tests these claims and finds statistically significant differences in the grant rate for both preliminary and permanent injunctions in copyright cases after the eBay decision. The impression of eBay lacking effect appears to be a product of hysteresis—a time lag between cause and effect, as lower courts initially delayed but eventually embraced eBay. This study reveals, moreover, that the earlier empirical study was flawed by biased sampling, most notably by including a large number of unreported cases and default judgments. This Article offers a corrective analysis and provides a more accurate understanding of the copyright injunction landscape, both pre- and post-eBay. It shows that eBay was in fact a landmark case for copyright law, both in terms of jurisprudence—it is highly cited—and real-world effect— it has a dramatic impact on case outcomes.

This paper introduces unemployment hysteresis into a tractable New Keynesian three equation model using an insider-outsider labour market. We demonstrate that strict inflation targeting can lead to a unit root in the unemployment rate, but dual mandate monetary policy can stabilise the economy around its efficient employment rate.

High level of unemployment persistence is important for Iran’s policy makers not only because of its weakening impacts on the whole economy, but also due to its social, political, and cultural consequences for the government stability. This paper tests the dynamics and hysteresis of the Iran’s unemployment rate disaggregated by territory (urban and rural), gender (male and female), and age groups (19-24, 25-30, 30 and more) covering the period 2001Q2-2020Q1. In all cases, our findings mostly support the hysteresis in unemployment and so shocks have a persistence effect on the unemployment subgroup series. When we extended the analysis to allow for two structural breaks with the GARCH unit root tests, this conclusion remains unaltered. The foregoing findings can help policymakers in each subgroup to design national and regional policies.

Does monetary policy have persistent effects on the productive capacity of the economy? Yes, we find that such effects are economically and statistically significant and last for over a decade based on: (1) identification of exogenous monetary policy fluctuations using the trilemma of international finance; (2) merged data from two new international historical cross-country databases reaching back to the nineteenth century; and (3) econometric methods robust to long-horizon inconsistent estimates. Notably, the capital stock and total factor productivity (TFP) exhibit strong hysteresis, whereas labor does not; and money is non-neutral for a much longer period of time than is customarily assumed. We show that a New Keynesian model with endogenous TFP growth can reconcile these empirical findings. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Since the birth of the natural rate hypothesis, the conventional notion that short-term output simply fluctuates around a relatively stable long-term trend became the norm in modern macroeconomics, including in the standard New Keynesian DSGE model. However, the global financial crisis (GFC) led to a serious rethinking of this norm, giving rise to the re-emergence of the Blanchard-Summers’ hysteresis debate and a new business cycle paradigm in which the short-term output effects of financial crises permanently feed into long-term growth trends. Using a Bayesian-estimated structural multivariate filtering model calibrated to data for Australia and the United States, the innovation of this paper is the incorporation of climate hysteresis into the estimation of potential output and the output and unemployment gaps. The results suggest non-trivia implications for monetary policy in a carbon-constrained world. Not only are the model-based estimates of potential output and NAIRU more volatile with climate shock persistence, the climate-neutral output and unemployment gap estimates are much smaller than conventional estimates, with different implications for inflation signals during the upturn or downturn of the business cycle. For economies that are more susceptible to disruptive climate shocks, especially in the developing world, an environment in which both demand conditions and the underlying supply potential are rapidly changing will severely complicate the conduct of forward-looking macroeconomic policy.

In the field of economics, hysteresis refers to an event in the economy that persists into the future, even after the factors that led to that event have been removed. The coronavirus pandemic (or COVID-19) had such an effect, one that will last even after humankind finds a means to purge it. In the same way, virtual hearings and remote advocacy are here to stay, long after COVID-19.

This article examines the dynamics of pandemic-induced uncertainty on credit growth, stock prices, economic activity, bond yields, and prices (assets and goods) in a panel dataset, recently assembled using IMF archives, of advanced and emerging economies. for this purpose, we implement a Symbolic Transfer Entropy approach proposed by Camacho et al. (2021), which represents an improved specification for detecting Granger-type causality in panel datasets. Specifically, this procedure yields a more robust specification when linearity assumptions break down, when in the presence of structural breaks, or when the data generating process is heterogeneous across the cross-section units. Aggregate economic variables are compared against the world pandemic uncertainty index (WPUI), which is based on the work of Ahir, Bloom, and Furceri (2020) and measures economic uncertainty related to pandemics and other disease outbreaks across the world. Amidst concerns that past economic shocks have left permanent scars on long-term growth, known as hysteresis, we find no robust evidence of a long-run causal effect between pandemic-induced uncertainty and most of key aggregate economic variables. On the other hand, the results indicate that pandemic jump tail risk is priced within equities.

Traditionally, economic growth and business cycles have been treated independently. However, the dependence of GDP levels on its history of shocks, what economists refer to as “hysteresis,” argues for unifying the analysis of growth and cycles. In this paper, we review the recent empirical and theoretical literature that motivates this paradigm shift. The renewed interest in hysteresis (or “scarring” in recent parlance) has been sparked by the persistent impact of the global financial crisis —as GDP in advanced economies remained far below the precrisis trends for over a decade—and recent concerns about the lasting impact of the COVID-19 shock. The findings of the recent literature have far-reaching conceptual and policy implications. In recessions, monetary and fiscal policies need to be more active to avoid the permanent scars of a downturn. And in good times, running a high-pressure economy could have permanent positive effects. (JEL E22, E23, E24, E32, E63, G01, O41)

We investigate and find evidence for the hysteresis hypothesis in UK imports from South Asian countries, using a monthly sample of data that covers 1999 to 2012. This paper finds evidence of the asymmetric effect of exchange rate volatility that ‘large’ depreciations significantly reduce UK imports from Bangladesh; however, ‘large’ appreciations do not increase the imports significantly. We also find a partial support for the hysteresis hypothesis in UK imports from India, Pakistan, and Sri Lanka. We find that hysteresis can be both country- and commodity-dependent, which is largely consistent with previous empirical studies. Theoretical literature suggests that hysteresis occurs due to the presence of sunk costs, however, we find that hysteresis occurs even beyond the sunk costs.

This paper examines the coevolution of land use and zoning in Seattle from 1920 to 2015. Multiple waves of zoning and land use conversion data at the parcel level allow for a decomposition of the long-run effects of zoning and an exploration of the mechanisms through which zoning influenced future land use. In particular, I disentangle short-run impacts on land use from long-term institutional hysteresis, showing that the latter played a sizable role in shaping future land use. Additionally, data on variances allows me to examine early compliance levels, an underexplored topic with implications for long-run impacts. While much has been written about persistence in urban form due to purely economic forces, relatively little research has explored how institutional forces can entrench or alter this trajectory, and I find that such institutional constraints can have substantial influence.

Hysteresis exists during the induction of and emergence from the anesthetic induced unconsciousness. Earlier researches considered this hysteresis as a pharmacokinetic delay, and its elimination has been the target of pharmacokinetics-pharmacodynamics (PK PD) model for anesthetic agents. However, recent animal studies suggested that the observed hysteresis may be an intrinsic characteristic of the neural system. Thus, investigating the anesthetic-induced hysteresis in human subjects during the full course of general anesthesia was needed. In this work, we employed bispectral index (BIS) as the index for anesthetic effect-site concentration. The anesthetic effect was tracked by the graph theory-based measures obtained from the brain functional networks that was estimated from 60-channel EEG data. The hysteresis in this work is defined as the discrepancy between the estimated graph theory-based measures at the same BIS level during the process of anesthesia induction and emergence. Our results showed that the hysteresis quantified by graph theory-based measures exists in both delta and beta bands. Further, the frontal lobe and parietal lobe were identified to be responsible for the observed hysteresis. Moreover, it was observed that the proposed hysteresis index was significantly correlated with the time duration of the anesthesia induction and emergence. These findings suggested that the hysteresis might be an intrinsic characteristic of the human neural system, and it should be taken into consideration when designing PK PD models for the anesthetics such as Propofol.

Changes in environmental conditions can lead to rapid shifts in the state of an ecosystem (“regime shifts”), which, even after the environment has returned to previous conditions, subsequently recovers slowly to the previous state (“hysteresis”). Large spatial and temporal scales of dynamics, and the lack of frameworks linking observations to models, are challenges to understanding and predicting ecosystem responses to perturbations. The naturally-occurring microecosystem inside leaves of the northern pitcher plant (Sarracenia purpurea) exhibits oligotrophic and eutrophic states that can be induced by adding insect prey. Here, we further develop a model for simulating these dynamics, parameterize it using data from a prey addition experiment and conduct a sensitivity analysis to identify critical zones within the parameter space. Simulations illustrate that the microecosystem model displays regime shifts and hysteresis. Parallel results were observed in the plant itself after experimental enrichment with prey. Decomposition rate of prey was the main driver of system dynamics, including the time the system remains in an anoxic state and the rate of return to an oxygenated state. Biological oxygen demand in fluenced the shape of the system’s return trajectory. The combination of simulated results, sensitivity analysis and use of empirical results to parameterize the model more precisely demonstrates that the Sarracenia microecosystem model displays behaviors qualitatively similar to models of larger ecological systems.

Infants represent the approximate number of items in visual and auditory arrays. These number representations are noisy: for example, whereas 6-month-olds discriminate numerosities that differ by a 1:2 ratio (e.g., 8 vs. 16 dots), they fail to discriminate a 2:3 ratio (e.g., 8 vs. 12 dots) until 9 months old. How should we understand the nature of the representations underlying this performance? One possibility is that the precision of approximate number representations is fixed at a given age; alternatively, precision may be dynamic and context dependent. Here we asked whether one aspect of context—prior numerical experience—influences preverbal approximate number precision. We familiarized 6-month-old infants with pairs of images containing different numerosities. Critically, as trials progressed, the ratio of the two numerosities within each pair also gradually progressed-- either from highly discriminable ratios to ratios that became harder to discriminate, or vice versa. After this ordered numerical training, we tested infants’ ability to discriminate numerosities differing by a challenging 2:3 ratio, with which infants of this age typically fail. In three experiments, we found that 6-month-old infants successfully discriminated the 2:3 ratio after starting with easy ratios and progressing to hard ones, but not after starting with hard ratios and progressing to easy ones, despite experiencing identical numerosities across these two conditions. This “numerical hysteresis” effect was feedback-dependent: infants only succeeded with the scaffolded training when they received trial-by-trial feedback. Together, these results provide evidence for a temporary modulation of infants’ number sense.

Ethical social welfare functions treat generations equally and respect Pareto improvements to non-null sets of generations. There are ‘perfect’ optima for such preferences: generations facing the same circumstances choose the same actions; and all circumstances are treated as possible. If each stationary policy determines a unique long-run distribution that is independent of the starting point, then there is a recursive formulation of policies that are simultaneously optimal for all of the preferences studied here. When the ergodic distribution can depend on early events (hysteresis), the curvature of the social welfare function determines the risks that society is willing to undertake and leads to a variant of the precautionary principle.

This paper analyses the following hitherto understudied feature in real switching options: a firm has a mothballing option and an option to permanently abandon. If the firm finds itself in an operating mode with a price just above the abandonment threshold, it is un-clear whether to exercise the abandonment option or to exercise the mothballing option. If the price goes down, the firm may exit, but, surprisingly, if it goes up, it may mothball. We find that two different strategies could be optimal: one where mothballing is not a viable option and one where mothballing does occur. In the latter case a hysteresis region arises in which the firm produces at a loss, while a further price decrease induces exit and a sufficient price increase results in the firm entering the mothballing stage. Mothballing being optimal requires sufficiently large values of the price trend and the uncertainty parameter. (C) 2018 Elsevier B.V. All rights reserved.

The global financial crisis has permanently lowered the path of GDP in all advanced economies. At the same time, and in response to rising government debt levels, many of these countries have been engaging in fiscal consolidations that have had a negative impact on growth rates. We empirically explore the connections between these two facts by extending to longer horizons the methodology of Blanchard and Leigh (2013) regarding fiscal policy multipliers. Our results provide support for the presence of strong hysteresis effects of fiscal policy. The large size of the effects points in the direction of self-defeating fiscal consolidations as suggested by DeLong and Summers (2012). Attempts to reduce debt via fiscal consolidations have very likely resulted in a higher debt to GDP ratio through their long-term negative impact on output.

Using monthly data of 79 Russian regions from 2003 to 2017, we study the long-run relationship of the retail gasoline prices with the crude oil price and the nominal exchange rate. We find that models that were successfully applied to deal with asymmetries in other countries are not suitable for Russia without taking structural breaks into account. Once breaks are allowed, we find that there is no asymmetry in the long-run elasticities between the gasoline prices and the crude oil price, and no significant hysteresis. However, there is an asymmetric relation between the gasoline price and the exchange rate that has decreased over time. These results also hold after several robustness checks. The evidence reported in this work shows that the effects of the exchange rate on gasoline prices are much more difficult to control than the oil price, and they require a larger set of policy measures: the recent development of a plan to decrease the importance of hydrocarbons exports by producing clean hydrogen using electrolysis and pyrolysis and the potential future export of electricity generated using nuclear power and onshore wind farms may help to diversify the local economy and to shield it from new sanctions.

Hysteresis has a significant role in evaluating hydrocarbon recovery and better understanding fluid flow in porous media. In this paper, a comprehensive review of research on the hysteresis of capillary pressure ( P c ) and its applications in petroleum engineering are reported. Both theoretical and experimental investigations of hysteresis of P c is compared and discussed in detail. The review highlights a range of concepts in existing models and experimental processes for hysteresis of P c in porous media. Furthermore, this paper tracks the current development of hysteresis and provides insight into future research trends. This study also serves to provide an insight into future research opportunities to fill the research gaps on capillary pressure in the system of porous media.

This paper uses administrative data to analyze a large and 8-year long employer payroll tax rate cut in Sweden for young workers aged 26 or less. We replicate previous results documenting that during the earlier years of the reform, it raised youth employment among the treated workers, driven by labor demand (as workers’ take-home wages did not respond). First, drawing on additional years of data, this paper then documents that the longer-run effects during the reform are twice as large as the medium-run effects. Second, we document novel labor-demand-driven “hysteresis” from this policy – i.e. persistent employment effects even after the subsidy no longer applies – along two dimensions. Over the lifecycle, employment effects persist even after workers age out of eligibility. Three years after the repeal, employment remains elevated at the maximal reform level in the formerly subsidized ages. These hysteresis effects more than double the direct employment effects of the reform. Discrimination against young workers in job posting fell during the reform and does not bounce back after repeal, potentially explaining our results.

Due to the increased availability of high-frequency measurements of stream chemistry provided by in situ sensors, researchers have gained more access to relationships between stream discharge and constituent concentrations (C-Q relationships) at event-scales. Existing studies reveal that event-scale C-Q relationships are mostly non-linear and exhibit temporal lags between peaks (or troughs) of hydrographs and chemographs, resulting in apparent hysteresis effects. In this paper, we summarize and introduce tools and methods in hysteresis analysis, especially the history and progresses of metrics to quantify hysteresis patterns. In addition, this paper provides a typical workflow to conduct event-scale hysteresis analysis, such as how to obtain the access to high-frequency measurements, existing methods to delineate storm events, approaches to classify and quantify hysteresis patterns, possible features/properties controlling hysteresis patterns, statistical methods to identify features at play, and strategies to deliver the inferences from hysteresis analysis. Lastly, we discuss some potential limitations that arise in the workflow and possible future work to address the challenges, including the development of advanced quantitative hysteresis metrics, generalized and standardized tools to delineate events and the integration of hysteresis analysis with numerical modeling. This paper aims to provide a critical overview of technical approaches for hysteresis analysis for researchers and hopefully foster their interests to advance our understanding of complex mechanisms in event-scale hydro-biogeochemical processes.

This paper provides a detailed understanding of the mechanism of traffic hysteresis and traffic oscillations from the driver behavior perspective. Microscopic evaluation of trajectories inside seven selected oscillations is performed to obtain a comprehensive picture of these puzzling phenomena. A new method based on driver’s task difficulty (TD) profile is proposed to capture changes in driver behavior in response to the disturbance caused by traffic oscillations. A close connection between the TD profile and evolution (such as formation and growth) of the stop- and -go traffic oscillations is found. Furthermore, driver behaviors inside the oscillations are identified based on driver’s TD profile, and their connection with hysteresis magnitudes is established. Finally, a generalized linear model suggests that variables related to traffic flow and driver characteristics are significant predictors of hysteresis magnitude. One noteworthy finding is that, the bigger the difference between the average TD levels between deceleration and acceleration phases of a vehicle trajectory, the larger the hysteresis magnitude becomes.

Time lags in switching operational modes are typical in the manufacturing and power sectors but are not treated in most real options models. In this paper, we consider a firm that has the opportunity to suspend and to resume production infinitely many times subject to a time lag after each startup decision. We contribute to the literature by allowing the firm to determine its level of installed capacity in conjunction with its optimal investment timing. We find that an increase in the length of the time lag results in an increase in the optimal capacity level. Capacity optimization also interacts with the length of the time lag to affect investment timing and the triggers to suspend and resume production, thereby weakening the result about hysteresis from a standard real options model. Under the assumption of a fixed level of capacity, a longer lag speeds up the decision to resume operations due to a positive upside to the revenue but delays the suspension of operations. By contrast, with capacity optimization, a longer time lag results in a larger capacity choice, which can indirectly delay the investment decision and the timing to resume operations. This indirect effect dominates when the level of market uncertainty is low and the time lag is initially small.

The 2008 economic downturn in the United States resulted in a wave of contractionary effects across many OECD countries. This paper investigates the pattern of the unemployment persistence in the United States and other 28 OECD countries before and after the Great Recession. To detect possible changes in the pattern of unemployment persistence, we employ a mean bias-corrected estimation of the persistence parameter with a rolling window of five years. In addition, we estimate the most likely date of change in the trend function of unemployment to test whether there was any significant change in the pattern of unemployment persistence after the Great Recession. We find significant evidence of a structural break and hysteresis in unemployment rates, with a persistence parameter close to unity, across the United States and other 28 OECD countries. Besides, bootstrap permutation tests show that all half-lives and impulse response functions have significantly changed after the Great Recession. Therefore, our findings call for structural reforms aimed at improving labor market performance, to prevent upward shifts in unemployment across OECD countries from becoming permanent.

This paper investigates the bipartite tracking problem for nonlinear multi-agent systems over signed directed graphs. Each agent is modeled by a higher-order nonlinear system in strict-feedback form with unknown dynamics and unknown hysteresis input. A distributed adaptive control law is proposed and analysed. Simulation results justify the proposed algorithm.

This article applies a recent econometric framework to the analysis of the relationship between energy consumption and economic growth in the US, which allows a joint study of causality and persistence. We provide evidence suggesting a nonlinear relationship with a structural break. In the most recent regime, we find that GDP causes energy consumption (and vice versa). Furthermore, both series show persistence, i.e., cyclical and natural components do not evolve independently. Thus, policies oriented to the reduction of energy consumption could constrain economic growth, and policy shocks can have permanent effects.

Organic-inorganic hybrid perovskite solar cells (HPSCs) are considered to be the most rapidly developed photovoltaic technology ever till date, portraying promising potential to replace the traditional silicon photovoltaics. In spite of such impressive growth, this technology is inundated with numerous challenges impeding the progress towards commercial viability. It is mainly due to the fact that the advancements in terms of performance efficiency were not equally matched with the fundamental understanding of inherent electronic and physio-chemical properties, modulating the photovoltaic parameters of the devices. Anomalous hysteresis observed in the current-voltage response of HPSCs is one of such major elusive issues prevalent in perovskite photovoltaics. Such hysteresis phenomenon could lead to erroneous estimation of the solar cell device efficiency, thereby its reliability during actual performance becomes questionable; serving as a serious obstacle for progress from both research as well as commercialization perspective. Hence, a detailed understanding of the origin of hysteresis and its associated mechanisms are highly indispensable. Though numerous theories have been proposed to elucidate the underlying causes of hysteresis, its origin is a highly debated topic till date and the most convincing answer is yet to be unraveled. The presented review takes an opportunity to elaborate various governing mechanisms or origins affecting the hysteresis phenomenon from a comprehensive yet insightful standpoint. This report also provides a concise synthesis of intricate interdependencies among the factors influencing hysteresis and highlights potential research strategies to develop hysteresis-free devices; rendering possible pathways to facilitate the viable commercialization of perovskite solar cells.

The key insight from this analysis is that monetary policy should be responding more to negative shocks than positive shocks: optimal monetary policy is asymmetric. Moreover, if we take the stance that asset prices indicate a high cost of exposure to long-run risks, this has very interesting implications for monetary policy that ripple through a surprisingly broad set of dimensions. There is an intuitive result that a Ramsey planner might wish to attenuate long-run risks (a key contributor to shifts in r-star). Less intuitively, I show that a Ramsey policymaker will induce a tolerance for skewness and a higher average inflation rate than is typically advocated in the literature. A variety of factors contribute to these results. First, deep non-linearities in the model entail that the policymaker behaves asymmetrically in its countercyclical policies. Second, the presence of capital generates longer-run effects (hysteresis) and additional tradeoffs, which implies that "countercyclical" in this model takes on a lower frequency theme. And third, imperfect competition leads to the pursuit of a higher average inflation rate to offset the related welfare costs.

This paper uses administrative data to analyze a large and 8-year long employer payroll tax rate cut in Sweden for young workers aged 26 or less. First, we document that while active, the reform raised youth employment among the treated workers. The long-run effects are twice as large as the medium-run effects and likely driven by labor demand (as workers' take-home wages did not respond). Second, we document novel labor-demand-driven "hysteresis" from this policy – i.e. persistent employment effects even after the subsidy no longer applies – along two dimensions. Over the lifecycle, employment effects persist even after workers age out of eligibility. Two years after the repeal, employment remains elevated at the maximal reform level in the formerly subsidized ages. These hysteresis effects triple the direct employment effects of the reform. Discrimination against young workers in job posting fell during the reform and does not bounce back after repeal, potentially explaining our results. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.