Self-selection Patterns Research Articles

Migration from developing countries: Selection, income elasticity, and Simpson’s paradox

The economic causes and effects of migration from developing countries depend on patterns of self-selection that are difficult to observe. We estimate the degree of migrant self-selection—on both observed and unobserved determinants of income—for 99 developing countries using nationally representative survey data on 653,613 people. In low-income countries, people actively preparing to emigrate have 14 percent higher incomes explained by observed traits such as schooling, and 12 percent higher incomes explained by unobserved traits. The simulated income elasticity of emigration is positive in the aggregate (+0.23) despite being negative in subpopulations, an instance of Simpson’s paradox.

Biomechanics of sit-to-stand with dual tasks in older adults with and without mild cognitive impairment

BackgroundThe decline in cognitive function in older adults with mild cognitive impairment (MCI) may contribute to a change in movement pattern during sit-to-stand transitions (STS). However, when comparing older adults with MCI to older adults without MCI, there is a lack of evidence of kinematic and kinetic data during STS. Furthermore, while significant cognitive dual-task interference has been demonstrated in older adults with MCI, studies on the effects of dual motor tasks in MCI, particularly during STS, have not been reported. Research questionAre there any differences in the movement time, joint angles, and maximum joint moments while performing STS under single- and dual-task conditions in older adults with and without MCI? MethodsIn a cross-sectional study, 70 participants were divided into two groups: older adults with MCI and without MCI. Motion analysis and a force plate system were used to collect and analyze the STS movement. All participants were asked to do the STS movement alone and the STS with a dual motor task with the self-selected pattern on an adjustable bench. ResultsOlder adults with MCI had greater maximum trunk flexion during STS with a dual task than older adults without MCI and greater than STS alone. Furthermore, older adults with MCI had a greater ankle plantar flexion moment during STS with a dual task than during STS alone. SignificanceEven though the STS task is one of the simplest functional activities, different strategies to achieve the STS action with dual tasks were found among older adults with and without MCI in terms of joint angle and joint moments.

High self-selection of Ukrainian refugees into Europe: Evidence from Kraków and Vienna.

Almost eight million Ukrainians have fled their country to escape the Russian full-scale invasion. To provide empirical evidence on how beneficiaries of temporary protection who reside in the immediate proximity of Ukraine differ from those who went further and reside in Western European countries, two large-scale rapid-response surveys were conducted in Kraków, Poland, and Vienna, Austria, in spring 2022. Data include information on socio-demographic characteristics, human capital, and return intentions of 472 and 1,094 adult Ukrainian refugees in Poland and Austria, respectively. Contributing to the growing empirical evidence on consistent assortative patterns in refugee inflows into Europe, our findings show that regularities in patterns of self-selection also occur in forced migration contexts where legal routes to safety apply. According to the analysed convenience sample, a tentative conclusion is that the further Ukrainian refugees moved to the West, the more self-selected they tend to be in the key dimensions of formal educational attainment, previous employment, language skills, and urbanity. Results indicate that willingness to stay in Kraków is significantly lower than willingness to remain in Vienna. This suggests that public financial support and living conditions, rather than diaspora networks, are decisive factors in shaping the decision to stay, move to another location or return to Ukraine. The aim to start a new life elsewhere may drive the motivation to choose a more distant destination instead of a neighboring country that allows to return rather quickly. Host countries should be aware of these specific characteristics of their refugee populations and adapt their integration policies accordingly.

Proactive personality and international student mobility: Patterns of self-selection and development

Proactive personality, i.e., individuals' disposition to take personal initiative and to initiate change, is a personality characteristic that is related to many favorable outcomes in the work domain and beyond. Yet, the conditions that promote its development amongst young adults have barely been researched. As international student mobility (ISM) has become an essential part of higher education in many countries, we assessed how proactive personality related to ISM experiences by self-selection, socialization and anticipation effects. We further explored if behavioural exploration served as a mediator of ISM socialization effects. We carried out a longitudinal study (N = 2163) with two measurement occasions and three study groups, i.e., control students who stayed at home, present sojourners who engaged in ISM and a waiting group of future sojourners. Latent change analyses indicated that all sojourners showed higher levels of proactive personality than control students before their departure abroad. Moreover, present sojourners increased in proactive personality as compared to the other two groups. This effect could partly be explained by sojourners' more frequent exploration of new behaviours. There was no indication that future sojourns affected proactivity development by anticipation effects. Implications of these findings for the understanding of adaptive personality development are discussed.

Comparison of Postural Control During Sit-To-Stand between Typically Developing Children Aged 4 to 12 Years and Young Adults

Postural control is a fundamental requirement for performing all functional tasks, including standing up from a chair. Although there is a broad literature on postural control development in typically developing (TD) children, there is a lack of specific information on TD children performing the sit-to-stand (STS). Therefore, the aim of this study was to investigate the development of postural control during STS in TD children of different age groups. Fifty-eight healthy TD children aged 4–12 years and 19 adults participated in this study. They were separated into four groups: 4–6 years, 7–9 years, 10–12 years, and adults. All participants were asked to perform the STS movement with a self-selected pattern. Participants' dynamic stability was quantified according to centre of mass (COM) displacement and velocity in the anterior-posterior, medial-lateral, and vertical directions during the four phases (flexion-momentum, momentum-transfer, extension, and stabilization) of the STS movement. The development of postural control was different in each phase of STS. During the flexion-momentum, extension, and stabilization phases, children aged 4–12 had higher COM displacements and velocities than adults. In the momentum-transfer phases, children aged 4-9 had higher COM displacements and velocities than other groups. In addition, children aged 4¬6 had the highest COM velocity during the extension phase of the STS movement. Children aged 4–12 years and adults used different strategies to control COM during STS movement. Adult-like postural control during STS was not found in children aged 10–12 years.

A test of the effort equalization hypothesis in children with cerebral palsy who have an asymmetric gait.

Healthy people can walk nearly effortlessly thanks to their instinctively adaptive gait patterns that tend to minimize metabolic energy consumption. However, the economy of gait is severely impaired in many neurological disorders such as stroke or cerebral palsy (CP). Moreover, self-selected asymmetry of impaired gait does not seem to unequivocally coincide with the minimal energy cost, suggesting the presence of other adaptive origins. Here, we used hemiparetic CP gait as a model to test the hypothesis that pathological asymmetric gait patterns are chosen to equalize the relative muscle efforts between the affected and unaffected limbs. We determined the relative muscle efforts for the ankle and knee extensors by relating extensor joint moments during gait to maximum moments obtained from all-out hopping reference test. During asymmetric CP gait, the unaffected limb generated greater ankle (1.36±0.15 vs 1.17±0.16 Nm/kg, p = 0.002) and knee (0.74±0.33 vs 0.44±0.19 Nm/kg, p = 0.007) extensor moments compared with the affected limb. Similarly, the maximum moment generation capacity was greater in the unaffected limb versus the affected limb (ankle extensors: 1.81±0.39 Nm/kg vs 1.51±0.34 Nm/kg, p = 0.033; knee extensors: 1.83±0.37 Nm/kg vs 1.34±0.38 Nm/kg, p = 0.021) in our force reference test. As a consequence, no differences were found in the relative efforts between unaffected and affected limb ankle extensors (77±12% vs 80±16%, p = 0.69) and knee extensors (41±17% vs 38±23%, p = 0.54). In conclusion, asymmetric CP gait resulted in similar relative muscle efforts between affected and unaffected limbs. The tendency for effort equalization may thus be an important driver of self-selected gait asymmetry patterns, and consequently advantageous for preventing fatigue of the weaker affected side musculature.

Behaviorally and environmentally induced non-24-hour sleep-wake rhythm disorder in sighted patients.

To determine whether there was evidence of circadian or sleep-regulatory dysfunction in sighted individuals with non-24-hour sleep-wake rhythm disorder. Three sighted individuals with signs and/or symptoms of non-24-hour sleep-wake rhythm disorder were studied. Thirty-five- to 332-day laboratory and home-based assessments of sleep-wake and circadian timing, endogenous circadian period, photic input to the circadian pacemaker, and/or circadian and sleep-wake-dependent regulation of sleep were conducted. No evidence of circadian dysfunction was found in these individuals. Instead, sleep-wake timing appeared to dissociate from the circadian timing system, and/or self-selected sleep-wake and associated light/dark timing shifted the circadian pacemaker later, rather than the circadian pacemaker determining sleep-wake timing. These findings suggest that the etiology of this disorder may be light- and/or behaviorally induced in some sighted people, which has implications for the successful treatment of this disorder. Emens JS, St Hilaire MA, Klerman EB, etal. Behaviorally and environmentally induced non-24-hour sleep-wake rhythm disorder in sighted patients. J Clin Sleep Med. 2022;18(2):453-459.

Rainfall and self-selection patterns in Mexico-US migration

Abstract This article studies the role of rainfall in determining the education composition of Mexico-US migration. Emphasizing the relationship between rainfall and migration costs, a revised Roy model indicates that rainfall affects selection on education through not only households’ liquidity constraints but also the comparisons between changes in migration costs and wage differentials at different levels of education. With retrospective data on the migration history of male Mexicans, the empirical analysis shows that the inverted U-shaped relationship between migration probabilities and education is less dispersed with a higher vertex when rainfall decreases, suggesting higher migration costs and reinforced self-selection patterns. The impacts of rainfall on selection and education are stronger for the migrant stock than for migration flows. Studying how rainfall influences migrants’ return decisions provides consistent results.

What students do early college high schools serve? Unpacking social constructions of the target population

To support the nation’s college completion goals, early college high school (ECHS) reform creates opportunities for interested students to earn up to two years of free college credit during high school. ECHSs also have an equity objective: to target and enroll students who are historically underrepresented and/or might not otherwise go to college. Yet the extent to which ECHSs actually serve their target population in practice is unclear, especially in a marketized school environment. Using qualitative methods and the theory of social construction and policy design (Schneider & Ingram, 1993), this study explores the recruitment and selection practices at five ECHSs in the borderlands of Texas. Findings suggest that ECHS staff invited applications from the broad target groups. However, the admission process, shaped in part by patterns of self-selection, favored students who were academically inclined and relatively privileged compared to their district peers. ECHS staff socially constructed narrower ideals of the target population than those articulated in the policy design based on their assumptions about who was likely to succeed in—and thus deserving of—an early college opportunity. Findings are discussed with particular attention to the equity implications of ECHS reform.

The development of sit-to-stand in typically developing children aged 4 to 12 years: Movement time, trunk and lower extremity joint angles, and joint moments

BackgroundSit-to-stand (STS) movement is an important transition movement for daily life. STS movement is typically seen in children aged 1 year and older. According to the motor development process, the ability of children in different age groups to perform STS movement would be different before they meet the mutuality. However, it is still unclear whether there are changes in the STS movement of growing children and adults. Research questionAre there any differences in the movement time, joint angles, and peak joint moments of STS in typically developing (TD) children? MethodsMotion analysis and the force plate system were used to analyze the STS movement in 77 healthy participants. All participants were asked to perform the STS movement using an adjustable bench with a self-selected pattern. Statistical analysis was done with respect to age (4–6, 7–9, 10–12, 18–25 years) and body height (1.00–1.20, 1.20–1.40, 1.40–1.60, 1.60–1.80 meters). ResultsChildren aged 4–6 years (or 1.0–1.20 m height) took less time to accomplish STS movement than adults (or 1.60–1.80 m height). Children aged 4–9 years performed STS movement by using more trunk and hip flexion and anterior pelvic tilt, but less knee flexion and ankle dorsiflexion than children aged 10–12 years and adults. At the final standing position, children aged 4–12 years exhibited more knee extension and more ankle plantar flexion than adults. In addition, children aged 4–12 years had more peak trunk-pelvic extension and less peak knee extension moments than adults. SignificanceDifferent strategies to achieve the STS task were found among children aged 4–12 years in terms of total movement time, joint angle, and joint moments. Adult-like kinematic and kinetic STS patterns were not seen in children up to 12 years old.

Feasibility of a Single-Subject Protocol to Shift Young Children's Sleep Schedules.

The objective of this study is to describe children's adherence to changing sleep schedules within a small-scale, single-subject, at-home sleep manipulation experiment. Subjects were six healthy children (male = 4, ages 6-8). Children underwent: baseline, a 7-day self-selected sleep pattern; Condition A1, a 3- to 12-day stabilized sleep pattern (assigned time into/out of bed set at baseline averages); Condition B, a 3- to 12-day phase-delayed sleep pattern (time into/out of bed 2h later than Condition A); and Condition A2, a 3- to 7-day return-to-stabilized sleep pattern (time into/out of bed at Baseline averages, identical to Condition A1). All children completed conditions. Per parent report, adherence to assigned time into/out of bed was good; sleep onset/offset adherence was variable. Within this small-scale, short-term sleep manipulation, children effectively got into/out of bed at assigned times despite manipulating sleep schedules by 2h. However, they struggle to shift their sleep onset and offset times to match the time they were in bed.

Do Migrants Think Differently? Evidence from Eastern European and Post-Soviet States

This research investigates migrant self-selection on values, beliefs, and attitudes using data from Eastern European and former Soviet countries. We find that individuals who intend to emigrate are more politically active, more critical of governance and institutions, more tolerant toward other cultures, less tolerant of cheating, more optimistic, and less risk averse. With the exception of risk aversion, all selection patterns are heterogeneous across regions of origin. On the other hand, no self-selection pattern is detected on education, willingness to pay for public goods, and economic liberalism. These findings provide new insights into the determinants of international migration and reveal some of its less known consequences, such as a possible reduction of domestic pressure for political improvements in post-Soviet states due to politically active citizens’ higher propensity to emigrate.

Self-Selection and Host Country Context in the Economic Assimilation of Political Refugees in the United States, Sweden, and Israel

We study the interplay between host countries’ characteristics and self-selection patterns in relation to refugees’ economic assimilation using a natural experiment in which immigrants from one region migrated to three destinations under similar circumstances. We focus on emigrants fleeing from Argentina and Chile during the military regimes there to the United States, Sweden, and Israel. We find that those refugees show patterns of selection and assimilation similar to those of economic immigrants. Immigrants to the United States and Israel exhibit better selection patterns and consequently faster assimilation than immigrants to Sweden even considering the positive effect of the Swedish market structure.

More Women in Tech? Evidence from a Field Experiment Addressing Social Identity

This paper investigates whether social identity considerations-through beliefs and norms- drive women's occupational choices. We implement two field experiments with potential applicants to a five-month software-coding program offered to women from low-income backgrounds in Peru and Mexico. When we correct the perception that women cannot succeed in technology by providing role models, information on returns and access to a female network, application rates double and the self-selection patterns change. Analysis of those patterns suggests that identity considerations act as barriers to entering the technology sector and that some high-cognitive skill women do not apply because of their high identity costs.

21.1 Effects of Self-Selected Patterns of Stimulant Medication on Growth in the MTA: Longitudinal Analyses of Relative Physical Size From Childhood to Adulthood

21.1 Effects of Self-Selected Patterns of Stimulant Medication on Growth in the MTA: Longitudinal Analyses of Relative Physical Size From Childhood to Adulthood

Interactive footsteps sounds modulate the sense of effort without affecting the kinematics and metabolic parameters during treadmill-walking

Previous research has shown that walkers provided with interactive simulations of footstep sounds on a surface material different from the one they are walking upon, experience pseudo-haptic illusions and adjust their walking kinematic according to the perceived surfaces’ compliance. Since walking on real grounds with different degrees of compliance leads to different metabolic costs, an open question is whether pseudo-haptic illusions created by interactive footstep sounds are able to affect the metabolic parameters.This study investigated whether metabolic cost and movement’s kinematics are affected by such interactive auditory feedback in a constrained condition as walking on a treadmill. Participants were walking on a treadmill under three listening conditions: actual footsteps sounds, interactive simulations of footstep sounds on gravel and snow. The metabolic and kinematic data, as well as the perceived exertion, sense of effort, easiness, and feeling of sinking were recorded.Results showed that interactive footstep sounds provided during treadmill walking did not affect kinematic and metabolic parameters of walking, while they were effective in modulating participants’ perception.These results suggest that in a constrained and non self-selected pattern of locomotion the sound of action, even though correctly perceived, is not strong enough to induce a change in the metabolic and kinematics of the locomotion.

Routine-biased technical change: Panel evidence of task orientation and wage effects

This analysis explores changes in the premium for abstract relative to routine tasks both across and within occupations over time. Previous theoretical and empirical work has linked growth in the relative task premium to changes in production technology that complement abstract but substitute for routine tasks, i.e. the Routine-Biased Technical Change hypothesis. The supporting empirical literature has relied almost exclusively on repeated cross-sections of workers and single cross-sections of task content. Thus, these studies have been unable to examine the evolution of wages in response to changes in task content within occupations over time and unable to control for unobserved individual and occupational heterogeneity. In this paper, I construct a new panel of occupational task content using incumbent-updated survey data from archived releases of the O*NET database. Estimating wage effects in a model with individual and occupation fixed-effects, I find that an increase of ten percentiles in the routine task distribution corresponds with a wage penalty of −0.09 to −0.35 percent in 2004 and declining to between −0.42 and −2.43 percent by 2013. In contrast, an increase of ten percentiles in the abstract task distribution corresponds with a wage penalty of 0.42–2.27 percent in 2004 and declining to between 0.42 and 2.43 percent by 2013. In contrasting estimates with and without individual fixed-effects, I also find evidence patterns of self-selection over time that are also consistent with the Routine-Biased Technical Change hypothesis.

Volunteer Participation in the Health eHeart Study: A Comparison with the US Population

Direct volunteer “eCohort” recruitment can be an efficient way of recruiting large numbers of participants, but there is potential for volunteer bias. We compared self-selected participants in the Health eHeart Study to participants in the National Health And Nutrition Examination Survey (NHANES) 2013–14, a cross-sectional survey of the US population. Compared with the US population (represented by 5,769 NHANES participants), the 12,280 Health eHeart participants with complete survey data were more likely to be female (adjusted odds ratio (ORadj) = 3.1; 95% confidence interval (CI) 2.9–3.5); less likely to be Black, Hispanic, or Asian versus White/non-Hispanic (ORadj’s = 0.4–0.6, p < 0.01); more likely to be college-educated (ORadj = 15.8 (13–19) versus ≤high school); more likely to have cardiovascular diseases and risk factors (ORadj’s = 1.1–2.8, p < 0.05) except diabetes (ORadj = 0.8 (0.7–0.9); more likely to be in excellent general health (ORadj = 0.6 (0.5–0.8) for “Good” versus “Excellent”); and less likely to be current smokers (ORadj = 0.3 (0.3–0.4)). While most self-selection patterns held for Health eHeart users of Bluetooth blood pressure cuff technology, there were some striking differences; for example, the gender ratio was reversed (ORadj = 0.6 (0.4–0.7) for female gender). Volunteer participation in this cardiovascular health-focused eCohort was not uniform among US adults nor for different components of the study.

Temporary and Permanent Migrant Selection: Theory and Evidence of Ability-Search Cost Dynamics

The migrant selection literature concentrates primarily on spatial patterns. We integrate two workhorses of the labor literature, the Roy and search models, to illustrate the implications of migration duration for patterns of selection. Theory and empirics show that temporary migrants are intermediately selected on education, with weaker selection on cognitive ability. Longer migration episodes lead to stronger positive selection on both education and ability because the associated jobs involve finer employee-employer matching and offer greater returns to experience. Networks are more valuable for permanent migration, where search costs are higher. Labor market frictions explain observed complex network-skill interactions. When considering migrant selection, the economics literature has largely focused on patterns by area of origin. However, the duration of migration episodes – temporary versus permanent – is another important determinant of selection. We integrate two workhorses of the labor literature, the Roy model and a search model, to illustrate the implications of migration duration for patterns of self-selection. We provide theoretical and empirical evidence showing that, because short-term migration episodes have less scope for skill-based matching and greater need for screening, temporary migrants are more likely to display intermediate selection on education, with weaker selection on underlying cognitive ability. Longer term migration episodes, in contrast, allow for finer employee-employer matching and greater returns to experience, leading to stronger positive selection on both education and cognitive ability among permanent migrants. Networks are also found to be more valuable for permanent migration, where search costs tend to be higher. However, we also provide evidence of complex network-skill interactions, driven primarily by labor market frictions.

Do Migrants Think Differently? Evidence from Eastern European and Post-Soviet States

This research investigates the effect of cultural traits on migration, by analyzing differences in norms, attitudes and beliefs between individuals who intend to emigrate and those who do not. The results show that cultural traits affect emigration decisions. Significant self-selection patterns are detected in some dimensions, such as evaluation of home country governance and institutions, political participation, trust in other people and justification of cheating, while they are absent in other dimensions, such as views on economic liberalism and democracy. Results also indicate that the relationship between cultural traits and migration are heterogeneous across regions with different institutions and culture. This analysis aims to improve our understanding of the determinants of emigration, as well as of its possible consequences on the dynamics of governance and institutions.