Similarity Hypothesis Research Articles

Scale dependence of local shearing motion in decaying turbulence generated by multiple-jet interaction

Scale dependence of local shearing motion is investigated experimentally in decaying homogeneous isotropic turbulence generated through multiple-jet interaction. The turbulent Reynolds number, based on the Taylor microscale, is between approximately 900 and 400. Velocity fields, measured using particle image velocimetry, are analysed through the triple decomposition of a low-pass filtered velocity gradient tensor, which quantifies the intensities of shear and rigid-body rotation at a given scale. These motions manifest predominantly as layer and tubular vortical structures, respectively. The scale dependence of the moments of velocity increments, associated with shear and rigid-body rotation, exhibits power-law behaviours. The scaling exponents for shear are in quantitative alignment with the anomalous scaling of the velocity structure functions, suggesting that velocity increments are influenced predominantly by shearing motion. In contrast, the exponents for rigid-body rotation are markedly smaller than those predicted by Kolmogorov scaling, reflecting the high intermittency of rigid-body rotation. The mean flow structure associated with shear at intermediate scales is investigated with conditional averages around locally intense shear regions in the filtered velocity field. The averaged flow field exhibits a shear layer structure with aspect ratio approximately 4.5, surrounded by rotating motion. The analysis at different scales reveals the existence of self-similar structures of shearing motion across various scales. The mean velocity jump across the shear layer increases with the layer thickness. This relationship is well predicted by Kolmogorov's second similarity hypothesis, which is useful in predicting the mean characteristics of shear layers across a wide range of scales.

Film Cooling Performances Under Various Upstream Roughness Conditions: Experimental Investigations and Similarity Hypothesis

Abstract Roughness caused by deposition, erosion, and additive manufacturing can significantly affect gas turbine efficiency. Previous research has often examined film cooling performance under limited roughness configurations, resulting in inconclusive findings. In this study, film cooling performances under various upstream roughness conditions were investigated to simulate the roughness-affected film cooling performance of the suction side and the endwall. Three roughness heights (k/D = 0.1, 0.2, and 0.4) and shapes (ks/k = 0.17, 0.67, and 1.95) were selected to cover a wide range of surface roughness characteristics. Three blowing ratios were examined (M = 0.5, 1.0, and 1.5). The weakly roughened surfaces showed improved cooling effectiveness as k/D increased. Meanwhile, the moderately and severely roughened surfaces showed a decrease in cooling effectiveness with increasing k/D at M = 0.5 and 1.0 but an increase at M = 1.5. Cases with shallower and higher roughness elements at M = 1.5 outperformed the smooth plate. Subsequently, a similarity hypothesis for film cooling effectiveness was proposed. At all blowing ratios, the scaled cooling effectiveness profiles converged around the smooth plate results for ks/D < 0.391, encompassing common turbine roughness scales, including irregularly roughened surfaces. Deviations emerged at ks/D = 0.782, and they were correlated with the deteriorated regions observed at various blowing ratios. Ensemble-averaged scaled cooling effectiveness exponentially grew with increasing roughness scale for all blowing ratios, and empirical expressions based on smooth plate result and roughness scale were proposed.

Synthesising models of primary school mathematicians by putting influencing factors of mathematics performance to the test

The gender-sensitive analysis of influencing factors on mathematical performance of primary school pupils can yield valuable insights into facilitating this vital phase of pupils’ educational trajectory. We view gender-sensitive mathematical performance in primary school based on works of Niklas (Psychologie in Erziehung und Unterricht, 62, 106, 2015) and Luttenberger et al. (Psychology Research and Behavior Management, 11, 311–322, 2018). All elements of their models can be assigned to structural traits of origin, home learning environment, interacting variables, and mathematics performance. These are presented and described in terms of gender. In our four-year long longitudinal study (n = 239) with four measurement points in primary school, the interplay and predictive power of these elements were analysed with structural equation model. Among the structural traits of origin, socio-economic status and migration background are relevant concerning precursor skills. The home learning environment is not relevant for precursor skills or later mathematics performance. The precursor skills and self-concept appear to be significant for mathematics performance whereas enjoyment of the subject does not matter. Gender affected only two measuring points of mathematics performance, so that the results support the gender similarity hypothesis according to Hyde (The American psychologist, 60, 581–592, 2005.) According to our study, school entry is not shaped by gender differences in social background, affective characteristics, or precursor skills. The results emphasize gender equality at the start of school, so that it is of interest for future studies to determine when and on the basis of which criteria performance differences develop in mathematics.

Model authenticity in learning mathematical experimentation: how students perceive and learn from scientist and peer models

The implementation of video modeling examples of mathematical hands-on experimentation may provide students with authentic and, at the same time, not too cognitively overwhelming experiences. However, the effectiveness of video modeling examples can be influenced by different characteristics of the observed models. On the one hand, based on the model-observer similarity hypothesis, it is likely that the observation of peers is particularly conducive to learning. On the other hand, from an authentic learning perspective, the presence of experts is considered to constitute a core design element of authentic learning settings which may foster motivational and cognitive learning outcomes. Against the background of these contradictory assumptions, the present study investigates the effects of observing models with different degrees of authenticity on students’ perceived authenticity, their situational interest, and their knowledge acquisition. We conducted an experimental study with 105 10th graders who observed either peer or scientist models performing a mathematical hands-on experiment in a video recording. As expected, the results show that students perceived the scientist models as more authentic than the peer models. Furthermore, we found neither a direct effect of condition nor an indirect effect mediated by students’ perceived authenticity of the observed models on students’ situational interest and knowledge acquisition. With this study, we contribute to the literature on the conditions and effects of authentic learning.

Forward and Inverse Energy Cascade in Fluid Turbulence Adhere to Kolmogorov's Refined Similarity Hypothesis.

We study fluctuations of the local energy cascade rate Φ_{ℓ} in turbulent flows at scales (ℓ) in the inertial range. According to the Kolmogorov refined similarity hypothesis (KRSH), relevant statistical properties of Φ_{ℓ} should depend on ε_{ℓ}, the viscous dissipation rate locally averaged over a sphere of size ℓ, rather than on the global average dissipation. However, the validity of KRSH applied to Φ_{ℓ} has not yet been tested from data. Conditional averages such as ⟨Φ_{ℓ}|ε_{ℓ}⟩ as well as of higher-order moments are measured from direct numerical simulations data, and results clearly adhere to the predictions from KRSH. Remarkably, the same is true when considering forward (Φ_{ℓ}>0) and inverse (Φ_{ℓ}<0) cascade events separately. Measured ratios of forward and inverse cascade probability densities conditioned on ε_{ℓ} also confirm the applicability of the KRSH to analysis of the fluctuation relation from nonequilibrium thermodynamics.

Plant trait dissimilarity increases competitive interactions among co‐occurring plants

Abstract Plant–plant interactions, often studied in the context of plant traits, are considered crucial assembly mechanisms for plant communities and offer insights into how neighbours affect growth. Three key questions regarding these interactions have theoretical importance but limited empirical support: (1) does similarity in plant traits enhance competitive interactions among species, (2) is the “competitive environment” determined through plant traits of the resident species, and (3) do greater species diversity and niche use result in increased competition among co‐occurring species. Here we use a simple experimental design to directly test these foundational questions. In a mesocosm experiment using native grassland fragments, we investigated our questions simultaneously by manipulating trait relationships among resident and colonizing plants. To assess the net impact of neighbours on plant growth, we measured the degree of suppression experienced by focal plants compared to growth in the absence of neighbours. We further tested whether trait‐function relationships are context‐dependent by modifying available resources. Contrary to the limiting similarity hypothesis, we found that reduced overall dissimilarity mitigated neighbour‐induced growth suppression, with more negative effects occurring among dissimilar neighbours. The influence of trait dissimilarity depended on nutrient context and was stronger under increased resource availability. We found little support for the idea that specific plant traits are “functional” in creating competitive environments: no community traits (community weighted means) were associated with net neighbour effects. In contrast, resource supply significantly affected species interactions, with increased resources exacerbating negative neighbour effects on plant growth. We found that plant trait dissimilarity does function in competition but is contingent on resource context. However, trait values were not inherently competitive: traits may have physiological functions but did not function in focal plants' competitive response. We provide some of the limited data directly testing the core mechanisms of community assembly. We encourage such direct experimental tests as they are essential to building an understanding of ecological processes. Read the free Plain Language Summary for this article on the Journal blog.

Autism Spectrum Disorder Traits and Empathy in Adolescents: The Similarity Hypothesis

Autism Spectrum Disorder Traits and Empathy in Adolescents: The Similarity Hypothesis

The income-happiness nexus: uncovering the importance of social comparison processes in subjective wellbeing

IntroductionPrevious research has established a positive correlation between income and subjective wellbeing (SWB). This correlation is attributed to income’s ability to provide material circumstances and influence one’s perceived socioeconomic rank in society, known as subjective socioeconomic status (SES).ObjectiveThis study sought to examine whether social comparison processes could mediate the relationship between income and SWB. Specifically, we aimed to explore the impact of comparing one’s current socioeconomic situation to individuals from a similar socioeconomic background (referred to as Comsim) on SWB, based on the similarity hypothesis of social comparison theory.MethodsData stem from two separate two-wave surveys. Study 1 comprised 588 participants, with 294 men and 294 women; age range 25–60 years; mean age 41.5 years). Study 2 comprised 614 participants, with 312 men and 302 women; age range 25–60 years; mean age 43.5 years. In both studies, data on predictors and SWB were collected 3 months apart.ResultsIn both study 1 and study 2, bivariate analysis demonstrated a positive correlation between income and SWB. However, multivariate regression models revealed that income did not have a direct effect on SWB. Instead, in both studies, subjective SES and Comsim emerged as significant predictors of SWB, with Comsim being the most influential. Furthermore, our formal mediation analysis indicated that subjective SES and Comsim fully mediated the relationship between income and SWB, when combined. Additionally, in study 2, we found that cognitive factors such as personal control, as well as affective factors like self-esteem, played a mediating role between the social comparison processes and SWB.ConclusionThis study contributes to existing research by emphasizing the importance of two distinct social comparison mechanisms in mediating the relationship between income and SWB.ImplicationsTherapeutic interventions to improve SWB should also consider social comparison processes. From a political standpoint, policies addressing income inequality can mitigate the negative effects of social comparisons on wellbeing. Providing support to those in lower socioeconomic positions can also enhance SWB.

Turbulent boundary layer flow over a three-dimensional sinusoidal surface

The sinusoidal roughness effect is investigated using a direct numerical simulation (DNS) of a spatially developing turbulent boundary layer (TBL) over three-dimensional sinusoidal roughness. The validity of Townsend's outer-layer similarity hypothesis is assessed based on comparisons of mean and second-order flow statistics, with a DNS of smooth-wall TBL data set at a similar Reynolds number. The total, Reynolds and dispersive stress tensors are calculated using the double-averaging procedure. The mean and second-order statistical similarities in the outer layer between rough-wall and smooth-wall TBLs are generally observed. The transport between total, turbulent and dispersive kinetic energy is investigated utilising triple-decomposed kinetic energy transports equations. The transport behaviour of turbulent kinetic energy (TKE) is significantly affected by the local mean shear induced by the surface roughness. However, the TKE transport shows good collapse with the smooth-wall case in the outer region of the flow. On the other hand, the transport of dispersive kinetic energy, including local production, redistribution and dissipation, are confined within the roughness sublayer. The intercomponent transfer between TKE and dispersive kinetic energy is quantified from the triple-decomposed kinetic energy transport equations. The intercomponent energy transfer is associated with the local spatial gradients of the turbulent momentum fluxes generated near the roughness canopy.

Comparative Study of Water Based on Microsoft Mathematics With Traditional Learning

The study aimed to see differences in learning outcomes in mathematics using AIR learning based on Microsoft Mathematics and traditional learning in class XI MAS Pondok Pesantren Modern K.H. Ahmad Dahlan Sipirok. This type of quantitative research uses test instruments. The sample consisted of 2 classes, namely the experimental class (AIR learning based on Microsoft Mathematics) and the control class (Traditional learning). Analysis of the data used is a prerequisite test using the average similarity test and hypothesis testing by calculating the average. The research hypotheses: 1) Knowing the increase in students' mathematics learning outcomes by using Water-Based Microsoft Mathematics learning and Traditional learning, 2) Knowing the differences in increasing mathematics learning outcomes between Water-Based Microsoft Mathematics learning and Traditional learning. After the research was carried out, the results showed that there were differences between learning Water-Based Microsoft Mathematics and Traditional learning. The average test of students' mathematics learning outcomes through AIR learning based on Microsoft Mathematics was obtained by 76.66% of the 30 students who took the test or met the minimum completeness criteria (KKM), namely 75%. And for the results of student activities to obtain an overall percentage value of 81%, and for the results of student activities to obtain an overall percentage value of 80%.&#x0D; Meanwhile, the average test score for students' mathematics learning outcomes through traditional learning reached 84.6% of the 25 students who took the test or met the minimum completeness criteria (KKM), namely 75%. And for the results of student activities to obtain an overall percentage value of 80%. Both learning are equally good to use in the learning learning process. However, it can be seen from the results obtained that traditional learning has higher results compared to AIR learning based on Microsoft Mathematics. One of the obstacles that causes this to happen is the lack of an internet network and frequent power outages. And for today's students, they miss the process of learning while playing. And they get it during the traditional learning process (bombing games)—Target Outcome of Scientific Publication in Sinta National Journal with ISSN.

Assessment of aerodynamic roughness parameters of turbulent boundary layers over barnacle-covered surfaces

Full-scale drag penalty predictions of flows over rough walls require surface roughness characterisation from laboratory experiments or numerical simulations. In either approach, it is necessary to determine the so-called equivalent sand-grain roughness height (k_s). There are several steps involved in determining this aerodynamic roughness lengthscale, but its procedure typically includes a combination of measurement of wall-shear stress (tau _w) using direct or indirect methods as well as analysis of velocity profiles. Indirect methods usually rely on assumptions made about flow and its scaling including the validity of universal outer-layer similarity. However, the implications of the underlying assumptions involved in full-scale drag prediction are unclear. In this work, we carry out wind tunnel measurements over a realistic rough surface (from a fouled ship-hull) to evaluate the impact of different methods with an emphasis on using the outer-layer similarity hypothesis for full-scale drag predictions. Wall-shear stress is measured using an in-house floating-element drag balance (DB), and velocity profiles are obtained using particle image velocimetry (PIV), allowing the evaluation of k_s, and the associated wake parameters through several methods. The aerodynamic roughness parameters hence obtained are used for full-scale drag penalty calculations. It is observed that the predicted drag penalty can vary by over 15% among the different methods highlighting the care that should be taken when employing such methods.

Semi-analytical modeling of sediment-laden open-channel flows with the effects of stratification, hindered settling, and eddy viscosities.

This study proposes semi-analytical models for simultaneous distribution of fluid velocity and suspended sediment concentration in an open-channel turbulent flow using three kinds of eddy viscosities. Apart from the classical parabolic eddy viscosity which is based on a log-law velocity profile, we consider two recently proposed eddy viscosities based on the concept of velocity and length scales. To deal with the flows with high sediment concentration, several turbulent features such as the hindered settling mechanism and the stratification effect are incorporated in the model. The governing system of highly nonlinear differential equations is solved using the homotopy analysis method (HAM), which produces solutions in the form of convergent series. Numerical and theoretical convergence analyses are provided for all three types of eddy viscosities. The effects of parameters on the derived models are discussed physically. Experimental data on both dilute and non-dilute flows are considered to verify the HAM-based solutions. The effects of the stratification correction factor (β) and the turbulent Schmidt number (α) reveal that they should be determined optimally for applicability of the proposed models in terms of accurate prediction with data. This optimal procedure required further investigation of these parameters, and, thus, an analysis of β and α is carried out, which linked them with the particle diameter through particle settling velocity, reference fluid velocity, and reference sediment concentration by proposing regression equations. Furthermore, using the optimal values of the parameters, the proposed models corresponding to the eddy viscosities based on the exponentially decreasing turbulent kinetic energy function and von Karman's similarity hypothesis are seen to be superior to the model corresponding to a parabolic eddy viscosity. Finally, a comment on the HAM is made where it is observed that the method can remove the numerical singularity of the governing equations at the water surface, which arises because of the consideration of vanishing eddy viscosity thereat.

Exploring the relationship between multiple dimensions of subjective socioeconomic status and self-reported physical and mental health: the mediating role of affect.

This study aimed to investigate the predictive effects of two types of subjective socioeconomic status on self-reported physical and mental health. Specifically, we examined the MacArthur Scale (MacArthur) which measures perceived socioeconomic rank in the society and a novel scale called ComSim, which assessed how participants compared themselves socioeconomically to others coming from a similar socioeconomic background. We also considered the influence of income, education, and personal relative deprivation (PRD) in these analyses. Additionally, we explored whether these effects were mediated through negative and positive affect. The data were collected through a cross-sectional, two-wave survey of 294 women and 294 men, with a mean age 41.6 years. Participants were recruited via an online platform. The results from multivariate regression models revealed that socioeconomic status measured with both the MacArthur Scale and ComSim significantly predicted both self-reported health measures, whereas income and education did not predict any of these measures in the full multivariate models. PRD only predicted self-reported mental health. Mediation analyses showed that negative and positive affect mediated the relationships between socioeconomic status measured by ComSim and self-reported health measures. These findings are discussed in the context of the similarity hypothesis of social comparison theory. The results underscore the importance of considering multiple dimensions when examining socioeconomic health disparities.

Mechanisms involved in alien maples (Acer sp.) invasion process in the Central Europe. Testing hypotheses associated with species fitness

Maples (Acer sp.) are trees/shrubs of extraordinary aesthetic value, what favours them for wide utilisation in urban greenery. However, some of the non-native species became invasive in the new range and represent a threat to natural ecosystems. Therefore, after the definition of their frequency and planting history in Slovak cities and reinvestigation of ecological status, based on analysis of growth, reproduction biology, fruit dispersal, phenotypic plasticity and allelopathic potential, invasion hypotheses related to the species fitness were tested in non-invasive alien species, in respect of invasive box elder (A. negundo L.). Parks and residential areas from the socialistic era were dominated by silver maple (A. saccharinum L.) and private gardens by palm maple (A. palmatum Thunb.) cultivars. A shift to ´locally naturalised´ was confirmed in the former, and palm maple was taken into consideration in the alien flora list (as casual). The fastest growth was found in silver maple and box elder. The latter showed also extraordinary reproduction earliness, largest fruit production, flight range and seed viability. Specific leaf area mostly decreased in box elder towards summer, indicating its large phenotypic plasticity. However, the largest allelopathic effect was observed in silver maple. Hence, ´limiting similarity hypothesis´, ´ideal weed hypothesis´, ´propagule pressure hypothesis´ and ´phenotypic plasticity hypothesis´ were essential for box elder invasion success. On the other hand, ´ideal weed hypothesis´ and ´novel weapon hypothesis´ seem to be crucial for silver maple naturalisation. Palm maple failed in all studied aspects, indicating colonisation stage of the invasion process.

Satisfaction and closeness in same- and cross-national college roommate relationships: What similarity matters?

Living with a cross-national roommate provides unique opportunities for college students to engage in cross-cultural learning and to form meaningful intercultural relationships. However, little is known about the challenges faced by college students in building a successful cross-national roommate relationship. Based on the similarity hypothesis, this study examined whether or not perceived dissimilarities in living habits or attitudes toward college life accounted for discrepancies between same- and cross-national roommate pairs’ closeness and satisfaction with their roommate relationships. Structural equation modelling with survey data from 479 students (66.4 % female; 13.6 % international students; 17 % with a cross-national roommate) living in on-campus residence halls in a large university in the US showed that college students experiencing cross-national roommate relationships perceived more dissimilarities in living habits and attitudes toward college life than those living with same-nationals, which in turn related to lower levels of roommate satisfaction and/or roommate closeness. However, when perceived dissimilarities along with other variables (including gender, roommate’s study participation status, and roommate assignment method) were controlled, they reported no less satisfaction and even higher levels of closeness than those living with same-national roommates. Findings suggest that the benefits of cross-national affiliations in college residence halls are more likely to occur if educators and staff can help students prepare for and manage perceptions of differences, especially in living habits.

Cyberbullying at work: an extension of traditional bullying or a new threat?

PurposeResearch comparing offline and cyberbullying is relatively sparse, with scholars suggesting the need for empirical investigations to clarify whether cyberbullying and offline bullying are similar or different constructs.Design/methodology/approachUsing an experimental vignette methodology, the current study of 163 working participants obtained via social media examines the effect of medium (offline vs cyberbullying), type (person-related vs work-related) and the interaction between medium and type on perceptions of definitional criteria (severity, frequency, power and intent) and outcomes (negative emotion, fairness, job satisfaction and turnover intention).FindingsSignificant differences between offline and cyberbullying were seen only for ratings of severity, job satisfaction and turnover intention, with cyberbullying perceived as more severe and as having a more detrimental impact on job satisfaction and turnover intention. Stronger effect sizes emerged for type of bullying, with person-related bullying having a stronger negative impact on definitional criteria and outcomes than work-related bullying. Moreover, interaction effects suggested differences between the two media were dependent on type of act – with person-related/cyberbullying acts seen more negatively than other acts.Originality/valueThis paper is the first to use a vignette approach to test the similarity or difference hypothesis between offline and cyberbullying. Overall, limited support is seen for the notion that offline bullying and cyberbullying are perceived as different constructs, with type of behaviour suggesting a more complex relationship between the two.

Influence of skewed three-dimensional sinusoidal surface roughness on turbulent boundary layers

The impact of roughness skewness (ksk) on turbulent boundary layer (TBL) flow with a zero pressure gradient over three-dimensional (3D) sinusoidal rough surfaces was experimentally investigated using a single hotwire anemometer. Nine 3D sinusoidal profiles were manufactured with positive, negative, and zero roughness skewness values. Measurements were taken at three different freestream velocities for each surface and compared with smooth wall TBL results. This study covered a range of friction Reynolds numbers (Reτ) from approximately 1000 to 4000, with δ/k≈20 ± 2, where δ represents the local boundary layer thickness, and k is the maximum height of the roughness, measured from the valley to peak. The results indicate that the wall-unit normalized streamwise mean velocity profiles for all rough surfaces exhibit a downward shift compared to the smooth wall profiles. Surfaces with positive roughness skewness produced the highest drag, leading to the largest downward shift. The friction coefficient (Cf) decreased as ksk decreased. The percentage increase in Cf and ΔU+ (the roughness function) was much larger when moving from negative to zero roughness skewness than when moving from zero to positive roughness skewness. The small differences in turbulence intensity profiles and higher-order turbulence statistics in the outer region of the TBL support the outer layer similarity hypothesis for the roughness considered in this study. The autocorrelation study revealed that surfaces with positive roughness skewness tend to shorten the average length of turbulence structures in the near-wall region.

Emotional design of pedagogical agents: the influence of enthusiasm and model-observer similarity

AbstractPedagogical agents were found to enhance learning but studies on the emotional effects of such agents are still missing. While first results show that pedagogical agents with an emotionally positive design might especially foster learning, these findings might depend on the gender of the agent and the learner. This study investigated whether emotional expressions performed by an on-screen instructor were able to increase learning outcomes while considering differences the gender of the agent and the learner. In a 2 (neutral vs. enthusiastic expressions) × 2 (female vs. male agent) between-subject design with additional consideration of the gender of the learner, data of 129 participants was collected. Results revealed that the manipulation of enthusiasm lead to higher perceptions of positive emotions. In addition, a pedagogical agent who performed enthusiastic expressions led to a higher retention but not transfer performance. In terms of the gender of the agent and the learner, male learners retained knowledge better when they watched the agent performing enthusiastic expression irrespective of the persona gender. Female learners, however, retained knowledge only better when a female agent performed enthusiastic expressions. Results are discussed in the light of the positivity principle, model-observer similarity hypotheses and current theories on social cues in multimedia learning.

Effects of Instructors' Character in Video Lectures: Does the Age of Lecturer Influence the Students' Learning Under Pandemic COVID-19?

This study investigated the impact of various age of online video lecturers on the learning performance of young college students, based on the previous studies about Model-Observer Similarity Hypothesis. Over the past few decades, many studies proved that learning is enhanced when the observer closely identifies with the model. Consequently, the present study aimed to examine how older or younger lecturers during two 10-minute videos influence the learning outcomes of young students (1), perceived similarity for each instructor of different ages (2), and the perceived explanation for each instructor (3), all other factors being equal. To test these hypotheses, a total of 20 (F = 14, M = 6) participants between the ages of 18 and 30 (F = 14, M = 6) were recruited from diverse college-student backgrounds and randomly assigned to two video lectures on Epigenetics and Behavioural genetics taught by either a younger or older instructor. The younger professor is less than 30 years old, whereas the elder lecturer is older than 40. The experiment's results were analysed using a paired sample t-test to evaluate these three hypotheses separately. All of the results were inconsistent with the model-observer hypothesis' expectations. It demonstrated that there is no significant difference between the learning performance of young students with regard to watch either younger or older instructor. Following that, it has been reported on the potential causes of contradictory results, limits, and prospective future applications.

Three nightmare traits (TNT) and the similarity effect determine which personality traits we like and dislike

We obtained free-text descriptions of liked and disliked others provided by 441 panel members (aged 24–26; 35 % male), who also completed the HEXACO PI-R in an online survey. Free-text descriptions were coded for HEXACO trait content by three judges. In line with the ‘three nightmare traits’ framework, we expected and found that language describing high levels of honesty-humility, agreeableness, and conscientiousness most distinguished liked from disliked targets (and vice versa for low levels). High extraversion also appeared in descriptions of liked targets, whereas low extraversion rarely appeared in descriptions of disliked targets. We also found support for the similarity hypothesis with participants higher in openness describing their liked (disliked) targets in terms of higher (lower) levels on this trait.