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Abstract Mounting evidence has shown that personality and behavioral syndromes have a substantial influence on interspecific interactions and individual fitness. However, the stability of covariation among multiple behavioral traits involved in antipredator responses has seldom been tested. Here, we investigate whether sex, gravidity, and parasite infestations influence the covariation between risk aversion (hiding time within a refuge) and escape response (immobility, escape distance) using a viviparous lizard, Zootoca vivipara, as a model system. Our results demonstrated a correlation between risk‐averse and escape behavior at the among‐individual level, but only in gravid females. We found no significant correlations in either males or neonates. A striking result was the loss of association in postparturition females. This suggests that the “risk‐averse – escape” syndrome is ephemeral and only emerges in response to constraints on locomotion driven by reproductive burden. Moreover, parasites have the potential to dissociate the correlations between risk aversion and escape response in gravid females, yet the causal chain requires further examination. Overall, our findings provide evidence of differences in the association between behaviors within the lifetime of an individual and indicate that individual states, sex, and life stages can together influence the stability of behavioral syndromes.

Purpose: The purpose of this study is to add to the current poverty dynamics literature by investigating the underlying causes of poverty persistence in Turkey, with an emphasis on both entry and exit rates. Methods: The study analyzes data from the Turkish Statistical Institute's "Survey on Income and Living Conditions" from 2018 to 2021 using dynamic probit models. This large dataset, which gives a detailed picture of socioeconomic situations, helps in properly understanding the complex aspects influencing poverty rates. Findings: The analysis reveals significant poverty persistence in Turkey, influenced by factors such as gender, marital status, employment, and health conditions. According to the research, these variables frequently interact, forming a complex structure that maintains poverty throughout the country. Implications: The findings necessitate targeted interventions to address persistent poverty, considering the diverse influencing factors. This could lead to a reduction in poverty rates and improved socioeconomic conditions for individuals. Originality/Value: This study offers a unique perspective on poverty dynamics in Turkey, focusing on both entry and exit rates. It provides valuable insights for those formulating policies or strategies aimed at poverty reduction, emphasizing the need for a comprehensive approach to poverty alleviation.

Geotechnical engineering often involves different types of geomaterials, such as sandy soil and clayey soil. Existing studies have confirmed that these soils have some common features, i.e. their mechanical behaviors depend not only on the inherent characteristics but also on their initial states. To describe the main mechanical behaviors of different soils within a simple and reasonable constitutive framework is of great significance for the numerical analysis on geotechnical engineering. This paper first introduces a model based on the concepts of superloading and subloading, which considers the “state dependence” (effects of overconsolidation and structure) of soil and only adds two material parameters compared with the Cam-Clay model. Secondly, conventional triaxial tests are systematically carried out on four types of soils (i.e. sand, silty clay, clay, and intermediate soil) with different initial void ratios, and the mechanical similarities and differences of these soils are discussed uniformly. After that, six material parameters of these soils are uniformly determined based on the concepts of superloading and subloading, and then used in constitutive calculations to verify the feasibility. The calculated results show a good agreement with test data, indicating that the model based on the concepts of superloading and subloading has great potential for describing the general mechanical behaviors of different soils within a unified framework. This work is expected to be applied to constitutive selection and parameter determination in the geotechnical numerical analysis of complex soil profiles.

Düşük ücretli istihdam hem gelişmiş hem de gelişmekte olan ülkelerin işgücü piyasasında yaygın bir şekilde görülen bir istihdam türüdür. Düşük ücretli istihdamın ortaya çıkmasının nedenlerinden biri düşük ücret kalıcılığıdır. Bu çalışmanın amacı Türkiye işgücü piyasasında düşük ücret kalıcılığının olup olmadığını ve düşük ücret kalıcılığının nedenlerini araştırmaktır. Düşük ücret kalıcılığı, Gelir ve Yaşam Koşulları Araştırması’ndan (GYKA) elde edilen 2013-2016 dönemine ait panel veriler kullanılarak başlangıç koşulları problemini dikkate alan örnek seçiminin olduğu içsel iki değişkenli probit modeli ile analiz edilmiştir. Ulaşılan sonuçlar başlangıç koşullarının göz önünde bulundurulması gerektiğini, Türkiye işgücü piyasasında düşük ücret kalıcılığının olduğunu ve bu kalıcılığın önemli bir kısmının gerçek duruma bağımlılıktan kaynaklandığını göstermiştir. Buna ilaveten düşük ücret kalıcılığının geriye kalan kısmının cinsiyet, eğitim seviyesi, vasıf ve firma büyüklüğü gibi gözlenen heterojenlik tarafından açıklanabildiği ortaya çıkmıştır.

Abstract The magnitude of global surface temperature change in response to unit radiative forcing depends on the type and magnitude of forcing agent—a concept known as a “forcing efficacy.” However, the mechanisms behind the forcing efficacy are still unclear. In this study, we perform a set of simulations using CESM1 to calculate the efficacy of 10 different forcing agents defined in terms of fixed‐SST effective radiative forcing, and then use a Green's function approach to show that each forcing efficacy can be largely understood in terms of the radiative feedbacks associated with the different surface temperature patterns induced by the forcing agents (a pattern effect). We also quantify how the state dependence of feedbacks on global mean surface temperature anomalies impacts forcing efficacies. The results show that the forcing efficacy can be well reconstructed with a combination of pattern effect and state dependence.

The original state-dependent fractional stress-dilatancy (FSD) equation for soils is developed based on the critical state lines (CSLs) with linear form. However, experimental evidences showed that the CSLs of soil in the $p^{\prime}$–$q$ and $e$–$p^{\prime}$ planes could be both nonlinear as well due to significant material degradation. This note aims to propose a unified FSD equation for soils with arbitrary types of CSLs. Detailed derivations are provided. To validate the proposed FSD equation, a series of triaxial test results of ballast and rockfill are simulated.

I denne artikkelen undersøker vi nærmere dynamikk og tilstandsavhengighet i det å være vanskeligstilt på boligmarkedet. Vi tar utgangspunkt i en operasjonalisering av vanskeligstilthet på boligmarkedet utarbeidet ved SSB: å tilhøre en lavinntektshusholdning i tillegg til å være trangbodd og/eller ha høy gjeldsbelastning. Om lag 3,5 prosent av alle bosatte i alderen 30–59 år ble regnet som vanskeligstilte i 2017 ifølge denne definisjonen. Vi finner betydelig utskifting i gruppen over tid. Av alle som er vanskeligstilte i et gitt år, er kun halvparten å finne som vanskeligstilte året etter. To år etter er 30 prosent fortsatt vanskeligstilte. Vi undersøker videre hva som kjennetegner personer som forblir vanskeligstilte over tid (vedvarende vanskeligstilte). Analysene tyder på at noen grupper ser ut til å være spesielt utsatte for å forbli vanskeligstilte over flere år. Dette gjelder særlig lavt utdannede og innvandrere. For yngre personer ser vanskeligstilthet i større grad ut til å være en midlertidig tilstand. Våre analyser er med på å belyse hvilke kriterier som ser ut til å være viktige for dynamiske aspekter av vanskeligstilthet. Dette kan være med på å bidra til videre diskusjon om empiriske definisjoner av vanskeligstilthet og bruk av relative inklusjonskriterier.11Artikkelen er en noe omarbeidet og utvidet versjon av kap. 4 i ISF-rapport 2019:2, Boforhold og velferd, finansiert av Kommunal- og moderniseringsdepartementet.

Abstract It was found that the constitutive behaviour of granular soil was dependent on its density and pressure (i.e. material state). To capture such state dependence, a variety of state variables were empirically proposed and introduced into the existing plastic potential functions, which inevitably resulted in the complexity and meaninglessness of some model parameters. The purpose of this study is to theoretically investigate the state-dependent non-associated behaviour of granular soils without using predefined plastic potential and state variable. A novel state-dependent non-associated model for granular soils is mathematically developed by incorporating the stress-fractional operator into the bounding surface plasticity. Unlike previous studies using empirical state variables, the soil state and non-associativity in this study are considered via analytical solution, where a state-dependent plastic flow rule and the corresponding hardening modulus without using additional plastic potentials are obtained. Possible mathematical connection with a well-known empirical state variable is also discussed. The non-associativity between plastic flow and loading directions as well as material hardening is found to be controlled by the fractional-derivative order. To validate the proposed approach, a series of drained and undrained triaxial test results of different granular soils are simulated and compared, where a good agreement between the model predictions and the corresponding test results is observed.

Abstract Conceptual and methodological tools from behavioral ecology can inform studies of habitat quality, and their potential for evaluating habitat restoration in conservation efforts is explored here. Such approaches provide mechanistic detail in understanding the relationship between organisms and their habitats and are thus more informative than correlations between density and habitat characteristics. Several Pacific salmon species have been the target of habitat restoration efforts for the past 2–3 decades, but most post‐restoration effectiveness studies have been limited to correlative data described above. In mark–recapture assays from four different study years, the affinity of sub‐yearling Chinook salmon (Oncorhynchus tschawytscha) and steelhead (O. mykiss) for stream pools restored with or created by engineered log structures was greater than that for pools without restoration, though with high interannual variability. From corresponding distribution and density data, it was clear that habitat affinity data are not always concordant with single observations of density. The same was true of the correlation between either affinity or density and physical characteristics of pools, although depth and current velocity had some explanatory power for both responses in Chinook. Movement into pools by Chinook during the assays indicated that restored pools can support more immigrants at a given density than can unrestored pools; however, no such pattern emerged for steelhead. Variation among individuals in body condition has implications for population‐wide fitness, and such low variation was correlated with stronger affinity for pools in Chinook regardless of restoration status. This suggests that pools may mediate habitat‐related trade‐offs and that restoring them might have a positive effect on fitness. Thus affinity, immigration, and condition data give much‐needed mechanistic indication of habitat selection for restored habitat via an apparent capacity increase and those potential fitness benefits. This is stronger support for restoration effectiveness than density differences alone because density data (1) may simply indicate redistribution of fish from poor to good habitats and (2) are not adequate to show correlations between restoration and positive change in traits correlated with fitness.

Abstract In many advanced welfare states, welfare recipients often receive benefits for long periods. This persistence of welfare receipt can be caused by two distinct mechanisms: genuine or spurious state dependence. Knowledge of which of the two mechanisms drives the observed state dependence is important because the policy implications are different. Most of the empirical evidence on state dependence relies on survey data. However, survey data on welfare receipt are subject to substantial measurement error (i.e., misreporting of welfare benefit receipt), which may also bias state dependence estimates. This paper uses rich linked survey and administrative data to measure the effect of misreporting in the survey data on the estimated state dependence in welfare receipt in Germany. We find a rate of underreporting of welfare benefits of 8.6%. Recipients with relatively good labour market chances tend to underreport benefits more frequently. Overreporting benefits is less pronounced with a rate of 1.6%. Within the survey data, we observe more transitions into and out of the welfare system. However, our estimates of state dependence in welfare receipt based on a dynamic random effects model reveal that the effect of misreporting on estimated state dependence is small, even when we distinguish between working and non-working recipients in the model.

We illustrate the R package cquad for conditional maximum likelihood estimation of the quadratic exponential (QE) model proposed by Bartolucci and Nigro (2010) for the analysis of binary panel data. The package also allows us to estimate certain modified versions of the QE model, which are based on alternative parametrizations, and it includes a function for the pseudo-conditional likelihood estimation of the dynamic logit model, as proposed by Bartolucci and Nigro (2012). We also illustrate a reduced version of this package that is available in Stata. The use of the main functions of this package is based on examples using labor market data.

Abstract Although high-intensity caregiving has been found to be associated with a greater prevalence of mental health problems, little is known about the specifics of this relationship. This study clarified the burden of informal caregivers quantitatively and provided policy implications for long-term care policies in countries with aging populations. Using data collected from a nationwide five-wave panel survey in Japan, I examined two causal relationships: (1) high-intensity caregiving and mental health of informal caregivers, and (2) high-intensity caregiving and continuation of caregiving. Considering the heterogeneity in high-intensity caregiving among informal caregivers, control function model which allows for heterogeneous treatment effects was used. This study uncovered three major findings. First, hours of caregiving was found to influence the continuation of high-intensity caregiving among non-working informal caregivers and irregular employees. Specifically, caregivers who experienced high-intensity caregiving (20–40 h) tended to continue with it to a greater degree than did caregivers who experienced ultra-high-intensity caregiving (40 h or more). Second, high-intensity caregiving was associated with worse mental health among non-working caregivers, but did not have any effect on the mental health of irregular employees. The control function model revealed that caregivers engaging in high-intensity caregiving who were moderately mentally healthy in the past tended to have serious mental illness currently. Third, non-working caregivers did not tend to continue high-intensity caregiving for more than three years, regardless of co-residential caregiving. This is because current high-intensity caregiving was not associated with the continuation of caregiving when I included high-intensity caregiving provided during the previous period in the regression. Overall, I noted distinct impacts of high-intensity caregiving on the mental health of informal caregivers and that such caregiving is persistent among non-working caregivers who experienced it for at least a year. Supporting non-working intensive caregivers as a public health issue should be considered a priority.

This paper presents a dynamic probit analysis of individual unemployment incidence using a panel survey on the National Socio-Economy (SUSENAS), 2008-2010. It compares a variety of dynamic random effects estimators, particularly focusing on the Heckman’s (1981) and Wooldridge’s (2005) approaches. The main result shows a strong evidence of persistence or state dependence of individual unemployment in Indonesia and therefore consistent with the theory of scar unemployment. This means that a person’s unemployment experience has an implication to his/her future of labour market experience.

Adversarial decision making is aimed at determining strategies to anticipate the behavior of an opponent trying to learn from our actions. One defense is to make decisions intended to confuse the opponent, although our rewards can be diminished. This idea has already been captured in an adversarial model introduced in a previous work, in which two agents separately issue responses to an unknown sequence of external inputs. Each agent’s reward depends on the current input and the responses of both agents. In this contribution, (a) we extend the original model by establishing stochastic dependence between an agent’s responses and the next input of the sequence, and (b) we study the design of time varying decision strategies for the extended model. The strategies obtained are compared against static strategies from theoretical and empirical points of view. The results show that time varying strategies outperform static ones

Off-farm labour participation is an important way in which farm households adapt their labour resources to farm labour needs, and is often viewed as an income integration and an insurance against risk. Nevertheless, it has also been questioned as a step for exiting agriculture. It is therefore important to assess whether or not it is a permanent status and which are its determinants. Most papers on this issue are based on cross-sectional analyses and thus disregard the problem of persistence in the state. Using a 5-wave panel of Italian family farms we estimate different dynamic nonlinear panel data models of the determinants of off-farm labour participation. We allow for two sources of persistence: unobserved heterogeneity and state dependence, and in addition we control for the initial conditions problem. We find a strong persistence in the state and our findings show that, when taking all these features into account, the present work state is almost totally explained by the previous state and by idiosyncratic characteristics. The variables concerning the farm and the farmer’s characteristics, typically found to be relevant in cross-sectional analyses, are not significant in the dynamic setting. The reasons for the inconsistency between our results and those of cross-sectional studies are discussed, and an interpretation of how the determinants influence the off-farm labour participation is presented. The distinction between true state dependence and individual heterogeneity has important policy implications that are discussed.

PurposeWe use the historical data from the European Study of Daily Fecundability and we develop an algorithm to determine the fertile window in a woman’s cycle according to the rules of the C.A.Me.N. symptothermal method proposed by the Centro Ambrosiano Metodi Naturali. Our aim is to identify variables acting on the probability of conception by considering the fertile window and factors that cannot be explained by employing the observed covariates of individuals and couples.MethodsWe adopt the latent Markov model with covariates tailored for data collected at times when a latent process detects the dependence across fertile periods of each woman’s cycle. We consider measurement errors, transitions between conception and non-conception, and the prediction of conception rate over the fertile windows.ConclusionWe find that the conception pattern is mainly related to sexual intercourse behavior during the fertile window and to previous pregnancies. For the cohort under study, we predict a steep decline in the average conception rate across fertile windows.

Brain-machine interfaces (BMIs) promise to improve the quality of life of patients suffering from sensory and motor disabilities by creating a direct communication channel between the brain and the external world. Yet, their performance is currently limited by the relatively small amount of information that can be decoded from neural activity recorded form the brain. We have recently proposed that such decoding performance may be improved when using state-dependent decoding algorithms that predict and discount the large component of the trial-to-trial variability of neural activity which is due to the dependence of neural responses on the network's current internal state. Here we tested this idea by using a bidirectional BMI to investigate the gain in performance arising from using a state-dependent decoding algorithm. This BMI, implemented in anesthetized rats, controlled the movement of a dynamical system using neural activity decoded from motor cortex and fed back to the brain the dynamical system's position by electrically microstimulating somatosensory cortex. We found that using state-dependent algorithms that tracked the dynamics of ongoing activity led to an increase in the amount of information extracted form neural activity by 22%, with a consequently increase in all of the indices measuring the BMI's performance in controlling the dynamical system. This suggests that state-dependent decoding algorithms may be used to enhance BMIs at moderate computational cost.

This study examines the extent state dependence among unemployed immigrants in a dynamic discrete choice framework. Three alternative methodologies are employed to control for the problem of the initial condition. The empirical findings show that there is a considerable correlation between the unobserved individual heterogeneity and the initial condition and that the degree of state dependence is overstated if we do not address this problem. The results show that an individual who was unemployed at period “t-1” has 6.5 percentage points higher probability of being unemployed again at period t compared to an individual who was employed at period “t-1”.

Brain-machine interfaces (BMIs) can improve the quality of life of patients with sensory and motor disabilities by both decoding motor intentions expressed by neural activity, and by encoding artificially sensed information into patterns of neural activity elicited by causal interventions on the neural tissue. Yet, current BMIs can exchange relatively small amounts of information with the brain. This problem has proved difficult to overcome by simply increasing the number of recording or stimulating electrodes, because trial-to-trial variability of neural activity partly arises from intrinsic factors (collectively known as the network state) that include ongoing spontaneous activity and neuromodulation, and so is shared among neurons. Here we review recent progress in characterizing the state dependence of neural responses, and in particular of how neural responses depend on endogenous slow fluctuations of network excitability. We then elaborate on how this knowledge may be used to increase the amount of information that BMIs exchange with brains. Knowledge of network state can be used to fine-tune the stimulation pattern that should reliably elicit a target neural response used to encode information in the brain, and to discount part of the trial-by-trial variability of neural responses, so that they can be decoded more accurately.

Several recent studies in invertebrates as well as vertebrates have demonstrated that neuronal response characteristics of sensory neurons can be profoundly affected by an animal's locomotor activity. The functional consequences of such state-dependent modulation have been a matter of intense debate. In flies, a particularly interesting finding was that tethered walking or flying causes not only general response enhancement of visual motion-sensitive neurons, but also broadens their temporal frequency tuning towards higher values. However, in other studies such state-dependent alterations of neuronal tuning functions were not found. We hypothesize that these discrepancies were due to different adaptation levels of the motion-sensitive neurons, resulting from the use of different stimulation protocols. This is plausible, because the strength of adaptation during ongoing stimulation was shown to be affected by chlordimeform (CDM), an agonist of the insect neuromodulator octopamine, which mediates state-dependent modulation. Our results show, that CDM causes broadening of the temporal frequency tuning of the blowfly's visual motion-sensitive H1 neuron only in the adapted state, but not prior to the presentation of adapting motion. Thus, our study indicates that seemingly conflicting results on the locomotor state-dependence of neuronal tuning functions are consistent when considering the neurons' adaptation level. Moreover, it demonstrates that stimulation history has to be considered when the significance of state-dependent modulation of sensory processing is interpreted.

Random-effect models have been useful in demonstrating how unobserved factors are related to infant or child death clustering. Another potential hypothesis is state dependence whereby the death of an older sibling affects the risk of death of a subsequent sibling. Probit regression models incorporating state dependence and unobserved heterogeneity are applied to the 1998 Demographic and Health Survey (DHS) data for Kenya. We find that mortality risks of adjacent siblings are dependent: a child whose preceding sibling died is 1.8 times more likely to die. After adjusting for unobserved heterogeneity, the death of the previous child accounts for 40% of child death clustering. Further, eliminating state dependence would reduce infant mortality among second- and higher-order births by 12.5%.