Limitations Of Theory Research Articles

Hidden tail chains and recurrence equations for dependence parameters associated with extremes of stationary higher-order Markov chains

Abstract We derive some key extremal features for stationary kth-order Markov chains that can be used to understand how the process moves between an extreme state and the body of the process. The chains are studied given that there is an exceedance of a threshold, as the threshold tends to the upper endpoint of the distribution. Unlike previous studies with $k>1$ , we consider processes where standard limit theory describes each extreme event as a single observation without any information about the transition to and from the body of the distribution. Our work uses different asymptotic theory which results in non-degenerate limit laws for such processes. We study the extremal properties of the initial distribution and the transition probability kernel of the Markov chain under weak assumptions for broad classes of extremal dependence structures that cover both asymptotically dependent and asymptotically independent Markov chains. For chains with $k>1$ , the transition of the chain away from the exceedance involves novel functions of the k previous states, in comparison to just the single value, when $k=1$ . This leads to an increase in the complexity of determining the form of this class of functions, their properties, and the method of their derivation in applications. We find that it is possible to derive an affine normalization, dependent on the threshold excess, such that non-degenerate limiting behaviour of the process, in the neighbourhood of the threshold excess, is assured for all lags. We find that these normalization functions have an attractive structure that has parallels to the Yule–Walker equations. Furthermore, the limiting process is always linear in the innovations. We illustrate the results with the study of kth-order stationary Markov chains with exponential margins based on widely studied families of copula dependence structures.

A GENERAL LIMIT THEORY FOR NONLINEAR FUNCTIONALS OF NONSTATIONARY TIME SERIES

New limit theory is provided for a wide class of sample variance and covariance functionals involving both nonstationary and stationary time series. Sample functionals of this type commonly appear in regression applications and the asymptotics are particularly relevant to estimation and inference in nonlinear nonstationary regressions that involve unit root, local unit root, or fractional processes. The limit theory is unusually general in that it covers both parametric and nonparametric regressions. Self-normalized versions of these statistics are considered that are useful in inference. Numerical evidence reveals interesting strong bimodality in the finite sample distributions of conventional self-normalized statistics similar to the bimodality that can arise in t-ratio statistics based on heavy tailed data. Bimodal behavior in these statistics is due to the presence of long memory innovations and is shown to persist for very large sample sizes even though the limit theory is Gaussian when the long memory innovations are stationary. Bimodality is shown to occur even in the limit theory when the long memory innovations are nonstationary. To address these complications, new self-normalized versions of the test statistics are introduced that deliver improved approximations that can be used for inference.

Application and Development of Behavioural Economics in Consumer Decision Making

Behavioural economics, as an interdisciplinary field integrating psychology and economics, offers new perspectives for understanding consumer decision-making. This paper provides an overview of the core theories of behavioural economics, its applications in consumer decision making, and its developments and challenges in market practice and policy making. First, behavioural economics challenges traditional economic assumptions about rational decision-making by revealing core concepts such as limited rationality, prospect theory and behavioural biases, providing a deeper understanding of consumer behaviour. Second, the paper explores the effectiveness of behavioural economics in practical applications, such as improving firms' market performance and policy implementation by optimising marketing strategies, utilising personalised recommendations and developing behavioural intervention policies. However, behavioural economics still faces challenges in terms of theoretical universality, cross-cultural applicability and dynamic adaptation. Future research directions include theoretical integration, cross-cultural validation, adaptation to technological developments, optimisation of policy practices and intersection studies with psychology. The review in this paper aims to provide reference for academic research and practical application, to promote the further development of behavioural economics, and to provide theoretical support for policy making and market strategies.

Global stability for McKean–Vlasov equations on large networks

Abstract We investigate the mean-field dynamics of stochastic McKean differential equations with heterogeneous particle interactions described by large network structures. To express a wide range of graphs, from dense to sparse structures, we incorporate the recently developed graph limit theory of graphops into the limiting McKean–Vlasov equations. Global stability of the splay steady state is proven via a generalised entropy method, leading to explicit graph structure-dependent decay rates. We highlight the robustness of the entropy approach by extending the results to the closely related Sakaguchi–Kuramoto model with intrinsic frequency distributions. We also present central examples of random graphs, such as power law graphs and the spherical graphop, and analyse the limitations of the applied methodology.

Fishes in Warming Waters, the Gill-Oxygen Limitation Theory and the Debate Around Mechanistic Growth Models

Mechanistic explanations of the impact of climate change on fish growth are currently under debate. However, critical assessments of even the most prominent theories are not always based on accurate interpretations of their underlying mechanistic models. This contribution addresses some of the major misunderstandings still causing the Gill-Oxygen Limitation Theory (GOLT) from being examined based on its actual structuring elements and assumptions, rather than erroneous perceptions. As we argue, recent critiques of the GOLT are based on implausible interpretations of respirometry data that are invoked to distinguish maintenance costs and overhead costs of growth. Discussing the current state of the debate, we emphasize the fact that fasting young and, thus, growing fish for short periods of time is not sufficient to suppress energy (i.e., oxygen) allocation to growth. In the process of dealing with these issues, several cases of apparent ‘counter-evidence’ are discussed. Highlighting the need to base critical discussions and examinations of the GOLT on its actual predictions, we recommend that testing the theory should focus on broad reviews or meta-analyses, e.g., on datasets of gill surface area and the relationship of these data to growth performance under different temperature regimes.

The White privilege of self-determination in entrepreneurship: how educational supports pipeline White students into business ownership

Worker cooperative entrepreneur spaces are predominantly White despite these companies building the foundation of their business model on equity and sustainability. While some studies have investigated racism in entrepreneurship development, no in-depth study has investigated White privilege in this space. Therefore, this study used a qualitative critical narrative analysis approach to explore White privilege in the entrepreneurship journeys of six White individuals who formed a worker cooperative business. Findings suggest that formal and informal educational experiences fostered four themes of White privilege in entrepreneurship: belongingness and competence in privileged entrepreneurship identity, resource-rich support systems, anti-meritocracy perceptions of competence, and privileged psychology of wealth. Findings suggest that educational spaces foster basic psychological needs of intrinsic motivation required for entrepreneurship, however, racialized gatekept access to these spaces perpetuates racial disproportionality in entrepreneurship. This article concludes with situating findings within self-determination theory and discussions of study limitations, implications, and future directions.

Towards a more globally inclusive academic discussion on local government: is more attention to Asian countries the answer?

ABSTRACT Asian countries’ growing importance in global affairs contrasts with the scant scholarly focus on their political, administrative, and governance practices. Our review of Local Government Studies from 1975 to 2024 shows limited articles on Asian governance. In addition, these studies chiefly concern developed regions in Asia, such as China, Japan, and South Korea, and focus on the public sector at the local government layer. Most of these studies are explanatory, adopting the frameworks derived from Western democracies to analyze political and administrative practices in Asian contexts. We suggest authors should pay more attention to Asian countries with limited scholarly attention, establish frameworks and theories specifically to analyze political and administrative practices in Asian contexts, conduct studies to investigate issues with high complexities and uncertainties, and apply diverse new and innovative research methods in conducting empirical studies.

The k-core in percolated dense graph sequences

Abstract We determine the order of the k-core in a large class of dense graph sequences. Let $G_n$ be a sequence of undirected, n-vertex graphs with edge weights $\{a^n_{i,j}\}_{i,j \in [n]}$ that converges to a graphon $W\colon[0,1]^2 \to [0,+\infty)$ in the cut metric. Keeping an edge (i,j) of $G_n$ with probability ${a^n_{i,j}}/{n}$ independently, we obtain a sequence of random graphs $G_n({1}/{n})$ . Using a branching process and the theory of dense graph limits, under mild assumptions we obtain the order of the k-core of random graphs $G_n({1}/{n})$ . Our result can also be used to obtain the threshold of appearance of a k-core of order n.

Interpretasi milenial Muhammad Shahrur tentang isu-isu perempuan

Background This study examines Muhammad Shahrur’s theory of limits and women’s issues. This theory adjusts the muhkamat verses to remain relevant to sociocultural conditions while remining within the jurisdiction of Allah SWT. Shahrur’s approach conveyed women as different from traditional ulemas and controversial. Therefore, it is necessary to describe Shahrur’s theory and interpretation of women’s issues. Methods This was an exploratory bibliographic study using descriptive-hermeneutic analysis. Two of Shahrur’s books were selected and five chapters from Al-Kitāb wa Al-Qur’ān, Qirā’ah Mu’āshirah and five chapters from Nahw Ushūl al-Jadīdah Li al-Fiqh al-Islāmy; Fiqh al-Mar’ah . Results Shahrur’s interpretations on women’s issues are: a) relationships between teenagers of the opposite sex without marriage or living together are “halal” if they follow their will without a contract and are accompanied by syecih, or permission; b) the maximum limit of the hijab is to cover the entire body except the face and palms. In contrast, the minimum limit covers the juyūb, including cleavage under the armpits, body parts, genitals, and buttocks. Apart from these, it does not include intimate parts and adapts to the community. c) Women’s intimate parts are shown only to the seven groups: brothers, fathers, children of a sibling, parents of one’s wives, and their children; d) Polygamy has both an upper limit and a lower limit. Shahrur allows polygamy under two conditions: widows with children whose husbands left them to protect them; polygamy has two limitations: a limit for quantity and a limit for quality; and e) the law of adultery has a lower and upper limit. Conclusion According to Shahrur, women’s issues are divided into four limits: sometimes they are at the upper limit and sometimes at the lower limit. Shahrur’s linguistic approach finally led him to draw the conclusion that the product of Islamic law is highly dependent on the sociocultural context.

Research progresses on the effects of light, temperature and water conditions on primary and secondary growth of trees.

Tree growth includes primary growth and secondary growth. The growth activity and dormancy cycle of trees can affect forest productivity and carbon sequestration capacity. Therefore, it is of great significance to examine the effects of environmental conditions (e.g., photoperiod, temperature and water) on tree growth for understanding the responses of trees to climate change and predicting forest productivity and carbon sequestration capacity under the background of global climate change. We reviewed the effects of photoperiod, temperature and water conditions on the primary and secondary growth of trees, and revealed the physiological mechanisms underlying their impacts on the synchronization or asynchronization between primary and secondary growth of trees. The shortcomings of the existing research were pointed out. For example, less attention had been paid to the enrionmental response and adaptation of root growth, as well as the physiological mechanism of the effect of light, temperature and water on tree growth. Research on the growth of underground roots should be strengthened in the future, and more attention should be paid to the physiological changes in the process of tree growth affected by environmental factors. Furthermore, the source and sink limitation theory and the process-based prediction model should be improved, aiming to provide a scientific basis for predicting forest productivity and carbon sequestration capacity and putting forward scientific policies of forest management.

Behavioural Economics in Marketing: Understanding consumer Decisison Making

Consumer decision-making, which is susceptible to emotional and social effects in addition to cognitive flaws, is the focus of behavioural economics, which integrates findings from economics and psychology. Examining the impact of behavioural economic principles such as limited rationality, prospect theory, and heuristics on customer behaviour, this abstract outlines important ideas and new developments in the field of applied behavioural economics to marketing. To determine which techniques are most successful in influencing customer decisions, we examine framing effects, anchoring, and nudging. Furthermore, the significance of data analytics and digital marketing in comprehending and capitalising on customer behaviour patterns is addressed. Businesses may boost engagement, happiness, and revenue by integrating behavioural data into marketing campaigns. In order to better understand consumer decision-making and its practical implications for marketers, the article also proposes topics for further research, such as the influence of new technology and ethical issues in consumer manipulation.

Reconstructing the Concept of Uang Panai in South Sulawesi: A Maqāṣid al-Sharī‘ah Approach for Revitalizing Women-Friendly Islamic Values

Uang panai is a significant issue that often hinders individuals from getting married due to the high financial demands imposed by the bride's family. These demands can sometimes thwart marriage aspirations. This study explores the reconstruction and revitalization of uang panai using Muhammad Syahrur's limit theory to make it more affordable and achievable for men. The research adopts a descriptive-analytical approach, a method that intricately describes specific phenomena or events and subsequently analyzes data to understand the emerging relationships and patterns. The findings indicate that by applying the minimum (al-hadd al-adna) and maximum (al-hadd al-a'la) limits, uang panai can be regulated based on the individual's income while maintaining the honor and dignity of the woman.

Influence of Wind Power Generation on the Steel Structure Design of Green Buildings

Wind power generation in renewable energy is the current research focus, but the relationship between wind power generation and green buildings is the basis for ensuring the stable operation of wind power generation, so it has become the current research focus. I propose a composite method based on the heat energy limit theory to study the relationship between wind power generation and the steel structure of green buildings, find the weak points of the steel structure in time, and ensure the continuous operation of wind power generation. The simulation results show that there is a negative correlation between wind power generation and green steel structure, and there is a close relationship between the design characteristics of the steel structure, the material and the installation method of wind power generation. The composite method proposed in this paper can monitor the operation effect of power generation at noon in time, and the accuracy of heat energy monitoring of steel structure can reach 80~90%, and the whole monitoring time is less than 15 seconds, which shows that the composite method proposed by us can provide support for the design and analysis of wind power generation and green steel structure buildings, and has theoretical feasibility. Therefore, strengthening the relationship between wind power generation and green steel structure design is the technical condition for the operation and implementation of steel structure, and it is also the guarantee of wind power generation.

Interlayer reinforced 3D printed concrete with recycled coarse aggregate: Shear properties and enhancement methods

In reinforced 3D printed concrete structures, the shear interaction between the rebar and the 3D printed filaments influences both the performance and safety of the concrete structures during service. In this study, the shear performance of the interlayer reinforced interface (IRI) of 3D printed concrete with recycled coarse aggregates (3DPRAC) was investigated, focusing on the pore structure characteristics of the interlayer interface. An enhancement method for the IRI was proposed by varying the number of anchored rebar nails (ARNs) and comparing the results with those of 3D printed concrete with natural coarse aggregates (3DPNAC) and 3D printed mortar (3DPM). The results showed that the ARNs significantly improved the IRI shear strength of 3DPRAC. Specifically, the IRI shear strength of 3DPRAC was 6.1 % lower than that of 3DPNAC but 43.6 % higher than that of 3DPM. By examining the structural characteristics of the rebar-3DPRAC bonding area, a relationship between pore defects and shear strength was established. This established relationship led to the proposal of a partition model for the interlayer bonding interface. A finite element model of 3D printed concrete incorporating real pore structure characteristics was developed to analyze the stress distribution and damage characteristics of the interface under shear stress. The fracture mode induced by local pores with the crack propagation mechanism was also analyzed. Finally, a unified formula for calculating the shear strength of the 3DPRAC IRI was derived based on the principles of virtual work and plastic limit theory. This study provides theoretical support for engineering applications of 3D printed reinforced concrete structures.

Sharia Economic Law Criticism on Muhammad Syahrûr’s Hudûd Theory Regarding Bank Interes

n modern economics applied by conventional financial institutions, the interest system is inseparable. Economic system based on sharia principles emerged as a solution to riba-based (usury-based) transactional activities, which in sharia economic law is in the khilafiyyah (dissent) territory amongst scholars regarding whether the conventional bank interest is riba which is prohibited by Islamic law. A figure named Muhammad Syahrûr came up and offered his theory of limits (nazhariyyah al-hudûd) in providing riba limitations in the Quran. This research aims to describe M. Syahrûr's thoughts on bank interest based on his theory of limits, and to analyze it based on the review of sharia economic law (fiqh muamalah mâliyyah). this reseach is understood as a literary study research which is a research on secondary materials. The type of data used in this research is secondary data, which is literature focusing on the thoughts of a figure, which is Muhammad Syahrûr.The result of the research shows that Muhammad Syahrûr's opininion that allows the practice of bank interest based on his theory of limits (nazhariyyah al-hudûd) is a marjûh (weak) opinion, since it is not supported by valid arguments and it also contradicts the opinions of the jumhur ulama (the majority of the scholars).

Poligami: Berdasarkan Konsep Keadilan dan Teori Limit Muhammad Syahrur

The discourse of polygamy is a topic that reaps the pros and cons among the Ulama’ and becomes a hot topic of discussion at the community level. Full attention of Islam regarding polygamy is not merely done without conditions, but Islam stipulates polygamy on the condition that is fair and there are restrictions on the number of wives. For his reason, reseaechers are interested in conducting deeper research on the concept of justice of polygamy practices which are still a topic of debate among the public based on the limit theory by Muhammad Syahrur. This research uses a critical descriptive research model using a methodological comparative study approach to analyze problems using the limit theory put forward by Muhammad Syahrur. This type of research is library research. Te source of this research is obtained from two legal materials, namely premier and secondary. This research uses isis analysis technique to find data to adjust the object to be studied by focusing on criticism. So that the results found that Syahrur argues that polygamy must be implemented when there has been a probem in society, but also must leave the practice when no problem is found. The concept of the limit theory put forward by heading the two conditions, including the first, namely that the second, third, or fourth wife is a widow who has an orphan, than the second is the fear of not being able to be fair to the orphan, as stated in Surah An-Nisa’ verse 3.

Promoting Decision Making and Behavioral Change: Application of Psychology and Behavioral Economics to Nudge Design

Nudge design is a design approach that uses people’s psychological preferences and cognitive limitations to guide people to make choices. The theoretical basis of nudge design mainly comes from psychology and behavioral economics, among which limited rationality theory, cognitive behavior theory, and Fun theory are important theoretical frameworks. This paper summarizes the basic contents of these three theories and their application examples in nudge design. By analyzing the relevant cases of nudge design, the application effects of these three theories in different fields and scenarios are expounded, such as public transportation, environmental protection, health management, education and training, etc., to provide reference and enlightenment for the theory and practice of nudge design.

Local smooth convergence of 𝔽-limit flows

The metric flow is introduced and extensively studied by Bamler [Compactness theory of the space of super Ricci flows, preprint (2020), arXiv:2008.09298; Structure theory of non-collapsed limits of Ricci flows, preprint (2020), arXiv:2009.03243], especially as an [Formula: see text]-limit of a sequence of smooth Ricci flows with uniformly bounded Nash entropy, in which case each regular point on the limit is a point of smooth convergence. In this note, we shall consider the [Formula: see text]-convergence of a sequence of [Formula: see text]-limit flows, and, like Bamler, show that each regular point on the limit is also a point of smooth convergence. The main result will be applied in another work of the authors [P.-Y. Chan, Z. Ma and Y. Zhang, Dimension reduction for positively curved steady solitons, preprint (2023), arXiv:2310.14020].

From law of the iterated logarithm to Zolotarev distance for supercritical branching processes in random environment

Consider (Zn)n⩾0 a supercritical branching process in an independent and identically distributed environment. Based on some recent development in martingale limit theory, we established law of the iterated logarithm, strong law of large numbers, invariance principle and optimal convergence rate in the central limit theorem under Zolotarev and Wasserstein distances of order p∈(0,2] for the process (logZn)n⩾0.

Natural Bioactive Compounds as Anti-aging Agents: Current and Future Perspectives

Abstract: Aging is a natural biological process that occurs due to various factors like unhealthy diet, environmental factors, genetic factors, and lack of moisture. This process leads to the loss of skin elasticity, also known as sagging. It happens due to the gradual decline of collagen type VII (Col-7) and fibril, which slows down the connection between the dermis and epidermis layers, causing the skin to look aged externally. There are several theories of aging, such as the free radical theory, membrane theory, DNA or genetic theory, neuroendocrine theory, telomerase theory, mitochondrial decline theory, and Hayflick limit theory. According to WHO, by 2030, one in six individuals worldwide will be 60 years or older. There are synthetic compounds available in the market for anti-aging purposes, but they pose various side effects. Natural products play an essential role in managing aging, and anti-aging phytoconstituents are mostly found in plant parts like fruits, stems, roots, and other plant sources that have no side effects. This review focuses on various anti-aging agents derived from plants and other natural sources.