In this paper, the stabilization problem of nonholonomic chained-form systems is addressed with uncertain constants. In this paper, the active disturbance rejection control is designed to solve this problem. The proposed control strategy combines extended state observer and adaptive sliding mode controller. The control of nonholonomic chained-form systems with dynamic nonlinear uncertain terms and uncertain constants is first discussed in this paper. In comparison with existing methods, the proposed method in this paper has better performance. It is proved that, with (...) the application of the proposed control strategy, semiglobal finite-time stabilization of the systems is achieved. An example is given to illustrate the effectiveness of the proposed method. (shrink)

Pharmaceutical sales representatives (PSRs) are one of the most frequently used drug information sources for physicians in both the United States and China. During face-to-face interactions, PSRs use various promotional strategies to impact the prescribing behavior. In the United States, PSRs provide physicians small gifts, free drug samples, and “sincere friendships”, whereas in China, they played an indispensable role in medical corruption over the past three decades. To cope with the undue influence of PSRs, both these countries have taken positive (...) but insufficient measures to eliminate the effect thus far. By comparing the strategies of American and Chinese PSRs, it was found that building a friendly personal relationship with physicians in a relatively closed private environment (such as physician’s office) is a key factor to exert an individualized influence on physicians, even in different social backgrounds and healthcare contexts. Therefore, this essay suggests that it is necessary to limit the establishment of personal relationships and maintain a more professional interaction to reduce the personalized psychological and emotional influences on physicians’ professional judgment. To achieve this goal, it is proposed to transfer the physician-PSR interaction to a professional public space as a supplement to current countermeasures and suggestions. The presence of others and the possibility of third party participation will stimulate more ethical and reputational concerns. It is hoped that the increased transparency of the interaction will promote participants to consider more professional norms and mitigate the undue influence of PSRs’ individualized strategies. (shrink)

ObjectiveProspective negative imagery is suggested to play an important role in the development and maintenance of anxiety and depression. The Prospective Imagery Task was developed to assess prospective imagery. Given the importance of prospective imagery for mental health in the Chinese cultural context, our objective was to examine the psychometric properties of the PIT in a Chinese sample.MethodsThe instrument was validated among a sample of 1,372 Chinese individuals who completed the PIT immediately following the Beck Depression Inventory-II and State-Trait Anxiety (...) Inventory-Trait version.ResultsThe two-factor structure of the PIT was in line with the original study, with satisfactory reliability and positive correlations with the BDI-II and STAI-T scores. Latent profile analysis revealed a three-class pattern. The measurement invariance indicated that the instrument can be used among different age groups as well as among males and females.ConclusionThe Chinese version of the PIT is a reliable and valid tool to measure prospective imagery, and the positive subscale is meaningful for clinical psychology. Limitations and future research directions are discussed. (shrink)

On the basis of PM2.5 data of the national air quality monitoring sites, local population data, and baseline all-cause mortality rate, PM2.5-related health economic benefits of the Air Improvement Action Plan implemented in Wuhan in 2013–2017 were investigated using health-impact and valuation functions. Annual avoided premature deaths driven by the average concentration of PM2.5 decrease were evaluated, and the economic benefits were computed by using the value of statistical life (VSL) method. Results showed that the number of avoided premature deaths (...) in Wuhan are 21,384 (95% confidence interval (CI): 15,004 to 27,255) during 2013–2017, due to the implementation of the Air Improvement Action Plan. According to the VSL method, the obtained economic benefits of Huangpi, Wuchang, Hongshan, Xinzhou, Jiang’an, Hanyang, Jiangxia, Qiaokou, Jianghan, Qingshan, Caidian, Dongxihu, and Hannan District were 8.55, 8.19, 8.04, 7.39, 5.78, 4.84, 4.37, 4.04, 3.90, 3.30, 2.87, 2.42, and 0.66 billion RMB (1 RMB = 0.1417 USD On 14 October 2019), respectively. These economic benefits added up to 64.35 billion RMB (95% CI: 45.15 to 82.02 billion RMB), accounting for 4.80% (95% CI: 3.37% to 6.12%) of the total GDP of Wuhan in 2017. Therefore, in the process of formulating a regional air quality improvement scheme, apart from establishing hierarchical emission-reduction standards and policies, policy makers should give integrated consideration to the relationship between regional economic development, environmental protection and residents’ health benefits. Furthermore, for improving air quality, air quality compensation mechanisms can be established on the basis of the status quo and trends of air quality, population distribution, and economic development factors. (shrink)

For the application of the standard genetic algorithm in illustration art design, there are still problems such as low search efficiency and high complexity. This paper proposes an illustration art design model based on operator and clustering optimization genetic algorithm. First, during the operation of the genetic algorithm, the values of the crossover probability and the mutation probability are dynamically adjusted according to the characteristics of the population to improve the search efficiency of the algorithm, then the k-medoids algorithm is (...) introduced to optimize the clustering of the genetic algorithm, and a cost function is used to carry out and evaluate the quality of clustering to optimize the complexity of the original algorithm. In addition, a multiobjective optimization genetic algorithm with complex constraints based on group classification is proposed. This algorithm focuses on the problem of group diversity and uses k-means cluster analysis operation to solve the problem of group diversity. The algorithm divides the entire group into four subgroups and assigns appropriate fitness values to reflect the optimal preservation strategy. A large number of computer simulation calculations show that the algorithm can obtain a widely distributed and uniform Pareto optimal solution, the evolution speed is fast, usually only a few iterations can achieve a good optimization effect, and finally the improved genetic algorithm is used to design the random illustration art. The example simulation shows that the improved algorithm proposed in this paper can achieve higher artistic and innovative illustration art design. (shrink)

Guided by the ecosystem theory, this study aimed to explore the association between parental autonomy support and future-oriented coping of high school students, as well as the mediating effects of future time perspective and meaning in life in this relationship. A total of 707 Chinese high school students were involved in a paper questionnaire survey and data analysis. It was found that parental autonomy support was significantly positively related to future-oriented coping. Mediation analyses demonstrated that parental autonomy support directly affects (...) future-oriented coping; parental autonomy support indirectly affects future-oriented coping through separate mediation and serial mediation of future time perspective and meaning in life. These findings have important implications for the improvement of future-oriented coping abilities of high school students. (shrink)

Behind the frequent occurrence of business scandals, it is often the silence and connivance of organizational immorality. Moral voice, a kind of employee active moral behavior, inhibits and prevents the organizational unethical phenomenon. Some researchers have sought to explore how to arouse employee moral voice. However, the limited studies mainly investigated the antecedents of leadership styles, ignoring the impact of the organizational factor on moral voice. Based on the self-determination theory, the current study constructs a theoretical model about how socially (...) responsible human resource management (SRHRM) affects employee moral voice via autonomous motivation and controlled motivation and further considering the moderating role of person–organization value fit. From a two-stage research method and the analysis of 260 valid data, we found that SRHRM promoted employee moral voice and this positive linkage was mediated by autonomous motivation but not by controlled motivation. Besides, the findings also revealed that person–organization fit moderated the indirect influences of SRHRM on moral voice via autonomous motivation, such that the indirect influence was stronger for a high level of person–organization value fit than the low level of person–organization value fit. Some theoretical and practical implications also be discussed. (shrink)

We present the interval-valued intuitionistic fuzzy ordered weighted cosine similarity measure in this paper, which combines the interval-valued intuitionistic fuzzy cosine similarity measure with the generalized ordered weighted averaging operator. The main advantage of the IVIFOWCS measure provides a parameterized family of similarity measures, and the decision maker can use the IVIFOWCS measure to consider a lot of possibilities and select the aggregation operator in accordance with his interests. We have studied some of its main properties and particular cases such (...) as the interval-valued intuitionistic fuzzy ordered weighted arithmetic cosine similarity measure and the interval-valued intuitionistic fuzzy maximum cosine similarity measure. The IVIFOWCS measure not only is a generalization of some similarity measure, but also it can deal with the correlation of different decision matrices for interval-valued intuitionistic fuzzy values. Furthermore, we present an application of IVIFOWCS measure to the group decision-making problem. Finally the existing similarity measures are compared with the IVIFOWCS measure by an illustrative example. (shrink)

Objective: Governments consistently aim to enhance services and establish online connections to efficiently deliver necessary information. This study aims to evaluate the future potential of digital libraries in public libraries in Pakistan by examining various projects that have introduced innovative approaches to foster the development of digital library services. Methodology: The analysis utilized the Amos 24 version, employing the Structural Equation Model (SEM) for assessing model fit indices and validating hypotheses. Additionally, Statistical Package for Social Sciences (SPSS) version 24 was (...) employed for Pearson correlation and factor analysis. Findings: The results suggest the appropriateness of discussing three out of the seven elements/factors used to assess competence improvement. The study reveals that public library managers can offer both physical and online workshops to community members, addressing emotional management for customers, including children and adults, during post-crisis information retrieval. Practical Implications: The study on public library user literacy skills, user behavior, and digital resources and services integrates the exploration and development of online databases to address challenges faced by public library management and users amidst the information explosion in academic and research activities. This contributes to enhancing the satisfaction levels of public library users. Originality/Value: Librarians are encouraged to conduct online workshops to address challenges faced by research students in information-seeking scenarios, focusing on improving reading and literacy skills, understanding user behavior, and optimizing digital resources and services through a study of online databases. (shrink)

Drawing on social exchange theory and benevolent leadership literature, we show how the largesse associated with benevolent leadership can cause subordinates to feel obliged to undertake illegitimate tasks assignments that go beyond their job duties. The hypotheses are tested in a scenario experimental study and a multisource, time-lagged field survey. Both studies indicate that benevolent leadership evokes indebtedness in subordinates (called felt obligation), which is then indirectly related to their willingness to undertake illegitimate tasks. The second study shows that subordinates (...) who try to avoid actions that damage relationships (called disintegration avoidance) and those who feel job insecurity are most willing to perform illegitimate assignments. Practical implications for curbing workplace exploitation are discussed. (shrink)

Prior research has shown that people can learn many nouns from a short series of ambiguous situations containing multiple words and objects. For successful cross-situational learning, people must approximately track which words and referents co-occur most frequently. This study investigates the effects of allowing some word-referent pairs to appear more frequently than others, as is true in real-world learning environments. Surprisingly, high-frequency pairs are not always learned better, but can also boost learning of other pairs. Using a recent associative model, (...) we explain how mixing pairs of different frequencies can bootstrap late learning of the low-frequency pairs based on early learning of higher frequency pairs. We also manipulate contextual diversity, the number of pairs a given pair appears with across training, since it is naturalistically confounded with frequency. The associative model has competing familiarity and uncertainty biases, and their interaction is able to capture the individual and combined effects of frequency and contextual diversity on human learning. Two other recent word-learning models do not account for the behavioral findings. (shrink)

In this paper, I advance an original view of the structure of space called Infinitesimal Gunk. This view says that every region of space can be further divided and some regions have infinitesimal size, where infinitesimals are understood in the framework of Robinson’s nonstandard analysis. This view, I argue, provides a novel reply to the inconsistency arguments proposed by Arntzenius and Russell, which have troubled a more familiar gunky approach. Moreover, it has important advantages over the alternative views these authors (...) suggested. Unlike Arntzenius’s proposal, it does not introduce regions with no interior. It also has a much richer measure theory than Russell’s proposal and does not retreat to mere finite additivity. (shrink)

This study examined the relationship between workplace sexual harassment as perceived by female employees and the family satisfaction of their husbands. It also considered the mediating roles of employees’ job tension and work-to-family conflict and the moderating role of employees’ work–home segmentation preference in this relationship. The results, based on data from 210 Chinese employee–spouse dyads collected at four time points, indicated that employees’ perceptions of sexual harassment were positively related to their job tension, which in turn increased WFC. Moreover, (...) WFC was negatively related to spouse family satisfaction. The negative relationship between sexual harassment and spouse family satisfaction was mediated by employees’ job tension and WFC. Finally, work–home segmentation preference attenuated the relationship between job tension and WFC. Our results provided insightful theoretical contributions and managerial implications for the sexual harassment and work–family literatures. (shrink)

This paper examines the relationship of ethical decision-making by individuals to corporate business ethics and organizational performance of three groups: SMEs, Outstanding SMEs and Large Enterprises, in order to provide a reference for Taiwanese entrepreneurs to practice better business ethics. The survey method involved random sampling of 132 enterprises within three groups. Some 524 out of 1320 questionnaires were valid. The survey results demonstrated that ethical decision-making by individuals, corporate business ethics and organizational performance are highly related. In summary, then, (...) high levels of organizational performance were directly attributable to high levels of applied corporate and individual ethics. Furthermore, there is a demonstrable tendency for Outstanding SMEs to reject ethically unsound practices such as padded expense accounts, tax evasion and misleading advertising. The measurement criteria used to assess organizational performance, however, did not include an objective evaluation of financial performance. (shrink)

Joint attention has been extensively studied in the developmental literature because of overwhelming evidence that the ability to socially coordinate visual attention to an object is essential to healthy developmental outcomes, including language learning. The goal of this study was to understand the complex system of sensory-motor behaviors that may underlie the establishment of joint attention between parents and toddlers. In an experimental task, parents and toddlers played together with multiple toys. We objectively measured joint attention—and the sensory-motor behaviors that (...) underlie it—using a dual head-mounted eye-tracking system and frame-by-frame coding of manual actions. By tracking the momentary visual fixations and hand actions of each participant, we precisely determined just how often they fixated on the same object at the same time, the visual behaviors that preceded joint attention and manual behaviors that preceded and co-occurred with joint attention. We found that multiple sequential sensory-motor patterns lead to joint attention. In addition, there are developmental changes in this multi-pathway system evidenced as variations in strength among multiple routes. We propose that coordinated visual attention between parents and toddlers is primarily a sensory-motor behavior. Skill in achieving coordinated visual attention in social settings—like skills in other sensory-motor domains—emerges from multiple pathways to the same functional end. (shrink)

Augustine was a representative of the theology of hope in the patristic age. He saw hope as the grasp of eschatological eternal happy life for human in this world. Together, the three virtues of faith, hope and love constitute the three interdependent faculties of the soul to know God. Hope, which comes from the grace of God given through Christ, is the knowledge of eternity, not of a future in time, and it helps one to resist the temptation of goods (...) which comes from the flesh and earthly things. Hope in eternity gives one a cognitive power beyond time and space, which leads to a unified vision of past, present and future, thus also causing important changes in how one lives in this created world. However, because of this unearthly hope, people can form a gradually expanding community of fraternity in this world, which helps them transcend differences of belief and seek a more virtuous life.Contribution: This article reconstructs Augustine’s interpretation of the nature of hope by synthesising his various texts, analysing the theological structure of the concepts related to hope, sorting out the ‘theology of hope’ he advocates and finally, in light of the wisdom of his philosophy, responding to what and how we can hope in suffering. (shrink)

As science has grown in size and scope, it has also presented a number of ethical and moral challenges. Approaching these challenges from an ethical framework can provide guidance when engaging with them. In this article, I place science within a virtue ethics framework, as discussed by Aristotle. By framing science within virtue ethics, I discuss what virtue ethics entails for the practicing scientist. Virtue ethics holds that each person should work towards her conception of flourishing where the virtues enable (...) her to realize that conception. The virtues must become part of the scientist’s character, undergirding her intentions and motivations, as well as the resulting decisions and actions. The virtue of phronêsis, or practical wisdom, is critical for cultivating virtue, enabling the moral agent to discern the appropriate actions for a particular situation. In exercising phronêsis, the scientist considers the situation from multiple perspectives for an in-depth and nuanced understanding of the situation, discerns the relevant factors, and settles upon an appropriate decision. I examine goods internal to a practice, which are constitutive of science practiced well and discuss the role of phronêsis when grappling with science’s ethical and moral features and how the scientist might exercise it. Although phronêsis is important for producing scientific knowledge, it is equally critical for working through the moral and ethical questions science poses. (shrink)

Lipstick is one of the most commonly used cosmetics, which is closely associated with female attractiveness and influences people’s perception and behavior. This study aimed to investigate the impact of light sources, lipstick colors, as well as gender on the subjective assessment of lipstick color products from the prospective of color preference, purchase intention and sexual attractiveness. The correlation between color preference evaluations when applying lipstick on lips and on forearms was also explored. Sixty participants completed their visual assessment of (...) 15 lipsticks worn by 3 models under 5 light sources, with uniformly sampled correlated color temperature (CCT) values ranging from 2,500 K to 6,500 K. The results indicated that the light source significantly influenced color preference and purchase intention, while lipstick color significantly impacted on sexual attractiveness. The interactions between gender and other factors were also observed and are discussed. Compared to men, women were found to be more sensitive to different light sources and hold different attitudes toward different lipstick colors under different CCTs. Interestingly, no significant correlation was found between lipstick color preference ratings on the lips and forearm, which conflicted with the commonly recognized way of lipstick color selection. These findings should contribute to a deeper understanding of the consumer attitude toward lipstick colors and provide a useful reference for lighting design in situations where cosmetics are specified, manufactured, retailed and generally used, both professionally and in the home. (shrink)

Weyl's tile argument purports to show that there are no natural distance functions in atomistic space that approximate Euclidean geometry. I advance a response to this argument that relies on a new account of distance in atomistic space, called "the mixed account," according to which local distances are primitive and other distances are derived from them. Under this account, atomistic space can approximate Euclidean space (and continuous space in general) very well. To motivate this account as a genuine solution to (...) Weyl's tile argument, I argue that this account is no less natural than the standard account of distance in continuous space. I also argue that the mixed account has distinctive advantages over Forrest's (1995) account in response to Weyl's tile argument, which can be considered as a restricted version of the mixed account. (shrink)

Due to the development of information technology, music piracy has become an escalating problem. This study attempts to employ the theory of planned behavior (TPB) and the social identity theory to investigate the antecedents of downloading pop music illegally from the Internet, the relationship between the intention to illegally download music and the intention to buy music, and the moderating effects of idolatry. Data were collected from 350 teenagers in Northern Taiwan through questionnaire interviews conducted in city centers where teenagers (...) gather. The results of partial least squares (PLS) analyses reconfirm the explanatory power of the TPB model with regard to the pop music illegal downloading behavior. However, it is interesting to note that the intention to illegally download music does not have a significant influence on the intention to buy music. This finding contradicts our common intuitions. Further analyses also reveal that idolatry moderates the relationship between the intention to illegally download music and the intention to buy music. For teenagers with high idolatry, a higher music downloading intention results in a lower buying intention. One possible explanation is the price of music CDs. Several interviews were also held to verify our results. Implications and a discussion are then provided. (shrink)

In this article I explain why scientists cannot always resolve their disagreements about experiments even if they do not hold conflicting theoretical assumptions, and how incommensurability in experiments can occur even if experiments are not deeply encumbered by theoretical assumptions. On the basis of recent discoveries in cognitive psychology and an extended analysis of a historical case, I explore a cognitive mechanism that may generate incommensurability in experiment appraisal. I find that, because of the involvement of goal-derived categories, incommensurability in (...) experiments may result from the conflict of goals that scientists pursue in their researches, from the differences of goal-derived classification schemata that they employ in analyzing experiments, and from discrepancies between skills that they have developed in their practices. This account differs from the conventional interpretation of Kuhn’s thesis, which attributes the cause of incommensurability solely to theoretical differences. In the conclusion, I further discuss the implications of this new account of incommensurability for both philosophical and historical studies of science. (shrink)

Due to the increasing number of people traveling by air, the passenger flow at the airport is increasing, and the problem of passenger drop-off and pickup has a huge impact on urban traffic. The difficulty of taking a taxi at the airport is still a hot issue in the society. Aiming at the problem of optimizing the allocation of taxi resource, this paper is based on the cost-benefit analysis method to determine the factors that affect the taxi driver’s decision-making. The (...) mathematical methods such as function equation, BP neural network algorithm, and queuing theory were used to establish a complete decision-making model for taxi drivers and an optimization model of dispatching efficiency at the airport. A conclusion has been drawn that the allocation of airport taxi resource should be arranged closely related to drivers’ revenue and the layout of airport line. (shrink)

In Indian logic, Nigrahasthāna (fault) generally refers to the occasion of defeat in debates. The fundamental theme of Vādanyāya is to discuss the issue of fault in debates. Based on the standpoint of Buddhist logic, Dharmakīrti in Vādanyāya, starting from the argumentative structure and rules of Buddhism, creatively developed the theory of fault in his debate logic, which can also be seen as a revision of the theory of fault in the Nyāya school. Delving into the logic and culture of (...) the Nyāya school, he critically analyzed and accepted various types of faults in the Nyāyan list of faults. Dharmakīrti’s thoughts about fault can be explored from four aspects: first, establishing the logical rationality of debate; second, innovating the classification criteria of faults; third, criticizing the theory of fault in the Nyāya school; and fourth, accepting the reasonable types of faults in the Nyāya school. (shrink)

Jin Yuelin 金嶽霖 was a Chinese philosopher and logician. From 1914 to 1920 he studied at the University of Pennsylvania and Columbia University, and received his Ph.D. in political science from Columbia in 1920. From 1921 until 1925, he studied in Europe and visited Great Britain, Germany, France, and Italy, among other countries. During these years, he studied at the London School of Economics and Political Sciences and at the University of Cambridge. At the end of 1925, Jin returned to (...) China and soon became a professor at Tsinghua University, where he began teaching logic in 1926. In 1931–1932, Jin went to Harvard University as a visiting scholar to study logic with the logician Henri M. Sheffer... (shrink)

This edited volume focuses on big data implications for computational social science and humanities from management to usage. The first part of the book covers geographic data, text corpus data, and social media data, and exemplifies their concrete applications in a wide range of fields including anthropology, economics, finance, geography, history, linguistics, political science, psychology, public health, and mass communications. The second part of the book provides a panoramic view of the development of big data in the fields of computational (...) social sciences and humanities. The following questions are addressed: why is there a need for novel data governance for this new type of data?, why is big data important for social scientists?, and how will it revolutionize the way social scientists conduct research? With the advent of the information age and technologies such as Web 2.0, ubiquitous computing, wearable devices, and the Internet of Things, digital society has fundamentally changed what we now know as "data", the very use of this data, and what we now call "knowledge". Big data has become the standard in social sciences, and has made these sciences more computational. Big Data in Computational Social Science and Humanities will appeal to graduate students and researchers working in the many subfields of the social sciences and humanities. (shrink)

The green economy is essential in supporting sustainable economic development and relies on talents and technologies. From the perspective of traditional economic theory, this study explores the impact of high-speed rail and innovation on the green economy from the perspectives of talent and technology. Using the data of 281 prefecture-level cities in China from 2008 to 2018, this study constructs empirical models to discuss the driving factors of the green economy. Empirical results show that high-speed rail and innovation can promote (...) the development of a green economy, and the opening of high-speed rail can strengthen the positive association between innovation and a green economy. The accessibility of high-speed rail improves the flow of talent between different cities and greatly stimulates the positive impact of innovation on green economic activities. In the further test, this study explores the impact of high-speed rail and innovation on the green economy from different dimensions, including government policy, economic strength, and administrative level. During China’s 12th Five-Year Plan, high-speed rail and innovation had a positive impact on the green economy, but the impact of innovation can still be significant after this period. Moreover, the opening of high-speed rail may motivate the migration of talents from developed cities to developing ones, while developed cities can rely on technological advantages to support green economic activities. Furthermore, low-administrative level cities will rely on attracting more talents to promote a green economy due to technological disadvantages. Innovation can play a critical role in enhancing the green economy of cities with high administrative levels. Talents and technology are both important to green economic activities, and the construction of high-speed rail changes the impact of technology on the green economy through the flow of talent. Our findings can explain why the opening of high-speed rail can promote the development of a green economy and effectively help governments achieve the goal of sustainable development. (shrink)

Our understanding of the complexity of the oral biome and of the role of the various constituent bacteria in the aetiology of dental disease is growing. Probiotics and their relationship with prebiotics, as well as other microbiome‐based interventions, could be useful in preventing and treating dental disease and in promoting oral health. However, given the promise and early stage of this treatment approach, there are also a number of ethical, social and regulatory issues associated with innovative probiotic therapy. In this (...) article, a brief update is given on contemporary theories of the aetiology and management of the two commonest dental diseases, and on the roles of pre‐ and probiotics and oral biome transplant in the management of these diseases. The focus is primarily on four core issues: informed consent, risk–benefit assessment, how to determine suitable healthy donors, and commercialization and regulation. We discuss the safety and benefits of oral probiotics, not only concerning the products and quality control during their manufacture, but also regarding the depth of public knowledge about this topic. We point out that the requirement of listing ingredients honestly might be insufficient, and that the prevalent rhetoric of ‘natural’ and ‘organic’ as well as some health claims in the translational, innovative probiotic industry and markets are themselves misleading and should be carefully scrutinized. Finally, we suggest an ethical imperative to find a balance between scientific research and industry, and public health in the regulation of probiotics. (shrink)

Examples from Chinese, Thai, and Finnish illustrate why researchers cannot always be confident about the precise nature of the word unit. Understanding ambiguities regarding where a word begins and ends, and how to model word recognition when many derivations of a word are possible, is essential for universal theories of reading applied to both developing and expert readers.