Information Theory Research Articles

Enhancing cross entropy with a linearly adaptive loss function for optimized classification performance

We propose the linearly adaptive cross entropy loss function. This is a novel measure derived from the information theory. In comparison to the standard cross entropy loss function, the proposed one has an additional term that depends on the predicted probability of the true class. This feature serves to enhance the optimization process in classification tasks involving one-hot encoded class labels. The proposed one has been evaluated on a ResNet-based model using the CIFAR-100 dataset. Preliminary results show that the proposed one consistently outperforms the standard cross entropy loss function in terms of classification accuracy. Moreover, the proposed one maintains simplicity, achieving practically the same efficiency to the traditional cross entropy loss. These findings suggest that our approach could broaden the scope for future research into loss function design.

Lightcone bounds for quantum circuit mapping via uncomplexity

Efficiently mapping quantum circuits onto hardware is integral for the quantum compilation process, wherein a circuit is modified in accordance with a quantum processor’s connectivity. Many techniques currently exist for solving this problem, wherein SWAP-gate overhead is usually prioritized as a cost metric. We reconstitute quantum circuit mapping using tools from quantum information theory, showing that a lower bound, which we dub the lightcone bound, emerges for a circuit executed on hardware. We also develop an initial placement algorithm based on graph similarity search, aiding us in optimally placing circuit qubits onto a device. 600 realistic benchmarks using the IBM Qiskit compiler and a brute-force method are then tested against the lightcone bound, with results unambiguously verifying the veracity of the bound, while permitting trustworthy estimations of minimal overhead in near-term realizations of quantum algorithms. This work constitutes the first use of quantum circuit uncomplexity to practically-relevant quantum computing.

Drought disaster risk assessment and yield insurance pricing of maize: a case study of Liaoning Province, China

Starting from the ‘four-factors’ theory of natural disaster risk formation, the study first selects indices that represent hazard, vulnerability, exposure, and emergency response and recovery capability to construct the drought risk assessment index system. Then the natural disaster risk index method is employed to evaluate the risk of maize drought disasters in Liaoning. Finally, the pure premium rate for maize yield insurance is determined based on the risk assessment results and the Copula function. The results show that: (1) The hazard, vulnerability, and exposure index in northwestern Liaoning are high, while emergency response and recovery capability is relatively low. Therefore, northwestern Liaoning is identified as a high-risk area for drought risk. (2) There exists a negative correlation between the drought risk index and maize yield in most areas of Liaoning; that is, higher drought risk is associated with lower maize yield. (3) Under the same coverage level, pure rates are higher in the northwestern and eastern Liaoning and relatively lower in the southwestern and southeastern Liaoning. Under different coverage levels, higher coverage corresponds to increased pure rates. The results can offer valuable guidance and benchmarks for relevant departments in Liaoning Province to assess the impact of drought risk on agriculture.

Group frames via magic states with applications to SIC-POVMs and MUBs

We connect magic (non-stabilizer) states, symmetric informationally complete positive operator valued measures (SIC-POVMs), and mutually unbiased bases (MUBs) in the context of group frames, and study their interplay. Magic states are quantum resources in the stabilizer formalism of quantum computation. SIC-POVMs and MUBs are fundamental structures in quantum information theory with many applications in quantum foundations, quantum state tomography, and quantum cryptography, etc. In this work, we study group frames constructed from some prominent magic states, and further investigate their applications. Our method exploits the orbit of discrete Heisenberg–Weyl group acting on an initial fiducial state. We quantify the distance of the group frames from SIC-POVMs and MUBs, respectively. As a simple corollary, we reproduce a complete family of MUBs of any prime dimensional system by introducing the concept of MUB fiducial states, analogous to the well-known SIC-POVM fiducial states. We present an intuitive and direct construction of MUB fiducial states via quantum T-gates, and demonstrate that for the qubit system, there are twelve MUB fiducial states, which coincide with the H-type magic states. We compare MUB fiducial states and SIC-POVM fiducial states from the perspective of magic resource for stabilizer quantum computation. We further pose the challenging issue of identifying all MUB fiducial states in general dimensions.

And Baby Makes Three: Postpartum Changes in Male–Female Affiliative Interactions in White‐Faced Capuchins

ABSTRACTIn group‐living primates, male investment in infants is highly variable. Previous research on polygynandrous primates found that male care of infants, whether direct or indirect, may be a means to increase offspring survival, increase social status, invest in future mating opportunities, and/or invest in future social or coalition partners, any of which may increase fitness outcomes. Relationships between male white‐faced capuchins (Cebus imitator) and infants are highly variable, ranging from neutral to highly affiliative during periods of group stability to lethal during times of instability. We used genetic paternity analysis and behavioral observations to investigate the impact of paternity status, female dominance rank, male dominance rank, and infant sex on changes in rates of affiliation (contact and proximity) between capuchin males and females following the birth of an infant (n = 92 dyads). We used generalized linear mixed models and an information theory approach to select models for averaging. We found that overall rates of male‐female affiliation increased following the birth of an infant (contact change: +1.09 ± 2.55%; proximity change: +1.16 ± 3.08%). Infant sex was the only significant explanatory variable; dyads that included males and females who gave birth to male infants experienced a significant increase in their time in contact and proximity in comparison to dyads with females who gave birth to female infants (contact change: p < 0.05 in 2/3 models; proximity change: p < 0.001 in 3/3 models). These findings add to previous data indicating that male capuchins do not recognize their offspring or have the motivation to preferentially invest in their care. We suggest that the observed sex bias may be a form of sex‐specific socialization connected to the importance of forming long‐term cooperative male bonds that are maintained via male parallel dispersal in this species.

A REVIEW OF THE LITERATURE ON DIGITAL ENTREPRENEURSHIP

Objective: This study aims to comprehensively review digital entrepreneurship (DE) research, identifying key themes, trends, and future research directions. Theoretical Framework: The review draws upon frameworks including entrepreneurial ecosystem theory, digital platform theory, and theories of entrepreneurial intention formation to understand DE dynamics. Method: A systematic and bibliometric analysis of 276 English-language articles published between 2000 and 2023 from the Scopus database was conducted. VOSviewer software analyzed publication trends, keywords, and citations. Results and Discussion: DE research has significantly grown, particularly in the last five years. Five thematic clusters emerged: DE ecosystems, cultivating digital entrepreneurs, entrepreneurship in the digital economy, exploring new frontiers, and sustainable, competitive digital enterprises. The study highlights influential works and emerging areas such as digital platforms, entrepreneurial intention, and DE education. The discussion contextualizes these findings within the theoretical frameworks and their implications. Research Implications: This research provides valuable insights for researchers, educators, and policymakers. It emphasizes the need for further research on the impact of digital technologies on entrepreneurial ecosystems, individual entrepreneurial intentions, and the role of education in fostering DE. Originality/Value: This study contributes by offering a comprehensive and up-to-date overview of DE research, identifying knowledge gaps, and proposing a future research agenda. The systematic approach utilizing bibliometric techniques provides a robust analysis of the DE literature, enhancing understanding of this evolving field.

Influence of Informational Internet Banking on Performance of Copedu PLC Microfinance

Purpose: This study investigates the influence of informational internet banking on the performance of COPEDU PLC Microfinance in Rwanda. It explores how access to online banking information affects customer satisfaction, retention, and overall financial performance. By focusing on non-transactional digital services, the study evaluates the extent to which informational internet banking impacts transparency, customer engagement, and financial literacy among clients. Methodology: The researcher employed a descriptive case study research design that integrated both qualitative and quantitative approaches. The study population comprised 74 individuals, and therefore, a census sampling technique was employed to select all 74 respondents. The researcher employed the SPSS software application to analyze the data. Mean, standard deviation, and percentages are utilized for data analysis. Pearson correlations were employed to establish the relationships among the variables. Findings: The regression analysis results demonstrated a significant correlation between the predictors (Informational internet banking, Transactional internet banking, and Communicative internet banking) and the dependent variable, Financial Performance, with a R value of 0.720, indicating a high degree of correlation. The R Square value of 0.519 signifies that around 51.9% of the variance in financial performance is elucidated by these predictors. The adjusted R Square of 0.497 provides a more precise estimate by considering the number of predictors in the model. A substantial majority of respondents (57.1%) agree that internet banking provides easy access to account information, reflected in a high mean score of 4.57. Additionally, 68.6% believe that the availability of internet banking services has improved customer satisfaction, with a mean of 4.64. The data suggests that informational internet banking has effectively reduced the need for in-person visits (61.4% agreement, mean 4.50) and has enhanced transparency in financial transactions (55.7% agreement, mean 4.56). Furthermore, respondents acknowledge that internet banking has positively impacted COPEDU's operational efficiency (57.1% agreement, mean 4.53) and improved the speed and convenience of accessing financial information (57.1% agreement, mean 4.49). Lastly, the provision of timely financial updates through internet banking was seen to contribute to better decision-making, with 50% of respondents agreeing (mean 4.44). Overall, the findings underscore the critical role of informational internet banking in enhancing customer satisfaction, operational efficiency, and informed decision-making at COPEDU PLC. In conclusion, the study demonstrates that informational internet banking significantly enhances customer satisfaction and operational efficiency at COPEDU PLC Microfinance, indicating its essential role in modern financial services. Unique Contribution to Theory, Practice and Policy: The research was underpinned by agency theory, contingency theory, behavioral theory, and information theory. It is recommended that COPEDU continues to invest in and promote its digital banking services, ensuring that clients are aware of the benefits and features available to them. For future research, it would be valuable to explore the long-term effects of digital banking on client retention and financial performance, as well as to examine the challenges and barriers faced by customers in utilizing these services effectively.

Strategies for comparison of modern probabilistic seismic hazard models and insights from the Germany and France border region

Abstract. The latest generation of national and regional probabilistic seismic hazard assessments (PSHAs) in Europe presents stakeholders with multiple representations of the hazard in many regions. This raises the question of why and by how much seismic hazard estimates between two or more models differ, not only where models overlap geographically but also where new models update existing ones. As modern PSHA incorporates increasingly complex analysis of epistemic uncertainty, the resulting hazard is represented not as a single value or spectrum but rather as probability distribution. Focusing on recent PSHA models for France and Germany, alongside the 2020 European Seismic Hazard Model, we explore the differences in model components and highlight the challenges and strategy for harmonising the different models into a common PSHA calculation software. We then quantify the differences in the source model and seismic hazard probability distributions using metrics based on information theory, illustrating their application to the Upper Rhine Graben region. Our analyses reveal the spatial variation in and complexity of model differences when viewed as probability distributions and highlight the need for more detailed transparency and replicability of the models when used as a basis for decision-making and engineering design.

Decoupling by Local Random Unitaries without Simultaneous Smoothing, and Applications to Multi-user Quantum Information Tasks

We show that a simple telescoping sum trick, together with the triangle inequality and a tensorisation property of expected-contractive coefficients of random channels, allow us to achieve general simultaneous decoupling for multiple users via local actions. Employing both old (Dupuis et al. in Commun Math Phys 328:251–284, 2014) and new methods (Dupuis in IEEE Trans Inf Theory 69:7784–7792, 2023), we obtain bounds on the expected deviation from ideal decoupling either in the one-shot setting in terms of smooth min-entropies, or the finite block length setting in terms of Rényi entropies. These bounds are essentially optimal without the need to address the simultaneous smoothing conjecture, which remains unresolved. This leads to one-shot, finite block length, and asymptotic achievability results for several tasks in quantum Shannon theory, including local randomness extraction of multiple parties, multi-party assisted entanglement concentration, multi-party quantum state merging, and quantum coding for the quantum multiple access channel. Because of the one-shot nature of our protocols, we obtain achievability results without the need for time-sharing, which at the same time leads to easy proofs of the asymptotic coding theorems. We show that our one-shot decoupling bounds furthermore yield achievable rates (so far only conjectured) for all four tasks in compound settings, which are additionally optimal for entanglement of assistance and state merging.

Noninvertible Symmetries Act Locally by Quantum Operations

of quantum field theories and many-body systems generalize the concept of symmetries by allowing noninvertible operations in addition to more ordinary invertible ones described by groups. The aim of this Letter is to point out that these noninvertible symmetries act on local operators by , i.e., completely positive maps between density matrices, which form a natural class of operations containing both unitary evolutions and measurements and play an important role in quantum information theory. This observation will be illustrated by the Kramers-Wannier duality of the one-dimensional quantum Ising chain, which is a prototypical example of noninvertible symmetry operations. Published by the American Physical Society 2024

Hamming distances of unsaturated orthogonal arrays

Orthogonal arrays (OAs) are applied in the statistical design of experiments, coding theory, cryptography, various types of software testing and quality control and have many connections to other combinatorial designs. The Hamming distances of OAs play a critical role in many areas such as algebraic combinatorics, quantum information theory, and wireless sensor networks. However, the calculation method of Hamming distances is difficult, especially for mixed orthogonal arrays (MOAs), since they rely on constructions or structures of OAs in many cases. In this article, by using the number of coincidences, we find some OAs with high strength and MOAs with strength 2 and 3, whose Hamming distances do not depend on their structures. We also calculate Hamming distances of a series of unsaturated asymmetrical OAs via their construction methods such as deleting columns, the expansive replacement method, and difference schemes.

Witnessing Entanglement and Quantum Correlations in Condensed Matter: A Review

AbstractThe detection and certification of entanglement and quantum correlations in materials is of fundamental and far‐reaching importance, and has seen significant recent progress. It impacts both the understanding of the basic science of quantum many‐body phenomena as well as the identification of systems suitable for novel technologies. Frameworks suitable to condensed matter that connect measurements to entanglement and coherence have been developed in the context of quantum information theory. These take the form of entanglement witnesses and quantum correlation measures.The underlying theory of these quantities, their relation to condensed matter experimental techniques, and their application to real materials are comprehensively reviewed. In addition, their usage in, e.g., protocols, the relative advantages and disadvantages of witnesses and measures, and future prospects in, e.g., correlated electrons, entanglement dynamics, and entangled spectroscopic probes, are presented. Consideration is given to the interdisciplinary nature of this emerging research and substantial ongoing progress by providing an accessible and practical treatment from fundamentals to application. Particular emphasis is placed on quantities accessible to collective measurements, including by susceptibility and spectroscopic techniques. This includes the magnetic susceptibility witness, one‐tangle, concurrence and two‐tangle, two‐site quantum discord, and quantum coherence measures such as the quantum Fisher information.

Entropy-based geometric measures of correlations for bell diagonal states via measurement

Abstract The classification and quantification of quantum correlations are the important issues in quantum information theory. Quantum relative entropy and Rényi relative entropy are both non-negative, and can therefore be regarded as generalized distances between quantum states. We first introduced the method proposed by Brodutch and Modi for constructing measurements of classical and quantum correlations. Subsequently, we use this method to construct measurement-induced geometric classical and quantum correlations based on quantum relative entropy and Rényi− 1 2 relative entropy. For two-qubit Bell diagonal states, the analytic expressions for these geometric classical correlations and quantum correlations are obtained.

Reputational Discrimination and Fairness in China's Social Credit System

As the first nationwide reputation system, the Chinese Social Credit System (SCS) employs a plethora of information technologies to rate citizens according to a state-defined notion of trustworthiness. Complementing extant research about the SCS that highlights important concerns regarding privacy and surveillance, our work explores the economic facets of the system on the basis of microeconomic and informational theories. We identify reputational discrimination as the basic working principle of the SCS, and propose that in addition to carrots and sticks, which are often highlighted as the main tools of the SCS to incentivize individuals to trustworthy behavior, status is another important variable the planner disposes of. Using a contest model approach, we find that when status is used as a complementary instrument to rewards and punishments, a planner who cares about efficiency, morality, and strictness treats most unfair those that are already bad off. Our work adds another dimension to the policy analysis of the SCS, and advances the understanding of the informational design of the SCS by investigating the fairness-related concerns that the system raises for individuals. Our findings underscore the importance of incorporating fairness principles into the SCS, to not further widen existing economic and societal gaps.

Statistical Response of ENSO Complexity to Initial Condition and Model Parameter Perturbations

Abstract Studying the response of a climate system to perturbations has practical significance. Standard methods in computing the trajectory-wise deviation caused by perturbations may suffer from the chaotic nature that makes the model error dominate the true response after a short lead time. Statistical response, which computes the return described by the statistics, provides a systematic way of reaching robust outcomes with an appropriate quantification of the uncertainty and extreme events. In this paper, information theory is applied to compute the statistical response and find the most sensitive perturbation direction of different El Niño–Southern Oscillation (ENSO) events to initial value and model parameter perturbations. Depending on the initial phase and the time horizon, different state variables contribute to the most sensitive perturbation direction. While initial perturbations in sea surface temperature (SST) and thermocline depth usually lead to the most significant response of SST at short and long ranges, respectively, initial adjustment of the zonal advection can be crucial to trigger strong statistical responses at medium range around 5–7 months, especially at the transient phases between El Niño and La Niña. It is also shown that the response in the variance triggered by external random forcing perturbations, such as the wind bursts, often dominates the mean response, making the resulting most sensitive direction very different from the trajectory-wise methods. Finally, despite the strong non-Gaussian climatology distributions, using Gaussian approximations in the information theory is efficient and accurate for computing the statistical response, allowing the method to be applied to sophisticated operational systems. Significance Statement The purpose of this work is to better understand how El Niño–Southern Oscillation (ENSO) responds to changes in its initial state and internal dynamics or external forcings. A statistical quantification of this response allows for the comprehension of the triggering conditions and the effect of climate change on the occurrence frequency and strength of each type of ENSO event. Such a study also allows to detect the most sensitive perturbation directions, which has practical significance in guiding anthropogenic activities. The approach used to study the response in this work is through the framework of information theory, which allows for an unbiased and robust assessment of the statistical response that is not affected by the turbulent dynamics of the system.

Quantum Entanglement and Nonlocality: Challenging the Local Realism of Classical Physics

Abstract. This paper delves into the significance and impact of quantum entanglement across the fields of physics, information science, and philosophy. Utilizing a literature review approach, the paper first introduces the concept and historical background of quantum entanglement, emphasizing its challenge to the limitations of classical physics and its potential applications in quantum communication and quantum computing. This paper thoroughly explains the theoretical foundations of the Einstein-Podolsky-Rosen experiment and Bell's inequality, along with related experimental validations and key results. In particular, it elucidates how quantum entanglement reveals the nonlocality in quantum mechanics and the characteristics of nonlocal information transfer. The discussion then shifts to the challenge quantum entanglement poses to physical ontology, exploring the philosophical implications and the new perspectives it offers in information theory. Finally, this study concludes by summarizing the profound impact of quantum entanglement as one of the most challenging and inspiring research areas in contemporary physics on scientific theory and philosophical thought, as well as anticipating future research directions and potential applications.

An experimental and numerical study on chloride transport in concrete under single bending load and coastal soft soil environment

This paper presents an experimental and numerical simulation study on the corrosion of chloride ions in concrete components, using a single pre-applied bending load to represent an additional bending moment caused by an external one-off disturbance. Besides, a novel correlation testing method, the Pearson-Mutual Information (PMI) method, is proposed based on Pearson correlation coefficients and mutual information theory. The findings indicate that a significant effect on chloride ion transport is only observed when the ratio of the applied bending load to the ultimate bending load (λ) exceeds 0.3. There is a distinctly positive and nonlinear relationship between λ and free chloride concentration (CCl), the apparent chloride diffusion coefficient (Da), as well as apparent surface chloride concentration (Cs). The bivariate time-varying model developed in this study demonstrates high fitting accuracy, with simulation results that closely correspond to actual measured data, achieving a coefficient of determination (R²) of 0.98 or higher. Furthermore, a sensitivity analysis of the model input parameters indicates that Cs is more sensitive than Da, and λ is identified as the key parameter. The impacts of the interfacial transition zone (ITZ) and its diffusion coefficient (Ditz) were found to be minimal on the output of the model.

Simondon’s Heterodox Naturalism: Form, Information and Self-Organization in Imagination and Invention

This article presents Simondon’s psycho-biological thinking as a type of heterodox naturalism centring on the self-organizing activity of vital forms. Despite his critique of classic notions of form, notably Aristotelian hylomorphism, Simondon revises this concept through a critical expansion and synthesis of information theory and Gestalt psychology. In his lecture series Imagination and Invention (1965–6) in particular, he develops an account of psycho-biological activity as governed by what he calls ‘images’: relatively autonomous informational sub-systems that serve to regulate the relationship between organism and environment and that constitute the condition for creative action or invention. Focusing on his analysis of the individualization of perceptual objects, the article goes on to show that ‘forms’ for Simondon feature as emergent properties of quantum thresholds of ‘information’ within these systems. It also argues that such a conception offers a more promising alternative to both idealist philosophies of perception and materialist interpretations of deconstruction.

Robust rateless space time block coding for mmWave massive MIMO system

In the vast growing wireless communication system creating robust encoding mechanisms using space-time block codes (STBC) for mmWave massive MIMO to overcome uncertainty and ensure reliability is a critical concept to be covered. This article reviews the core concepts behind MIMO communication, Massive MIMO communication, space-time block codes, and rateless codes in the context of wireless communication systems. Building on the foundational concepts of information theory and mmWave massive MIMO, we developed space-time block codes that maintain orthogonality for real-valued symbols. Following a thorough analysis of these codes, we successfully extended them into rateless orthogonal space-time block codes (ROSTBC) for massive MIMO. This extension enables the codes to adapt their rates dynamically based on the unknown channel conditions at the transmitter. The research work was concluded by comparing static G4 encoded Tarokah work and other Orthogonal Space Time Block Codes (OSTBCs) with Rateless Space Time Block Codes (ROSTBCs). The results show that as the number of blocks used to encode the message in Rateless Space Time Block Code (ROSTBC) increases, this coding scheme can outperform static Rateless Space Time Block Codes (OSTBC) in very low SNR values by a minimum of 8.5 %. This work can enhance wireless communication by creating reliable communication over inherently unreliable systems.

Orthogonal Decompositions of Regular Graphs and Designing Tree-Hamming Codes

The paper introduces a concept of graph decomposition. That is orthogonal decompositions. Orthogonal decompositions of a graph H is a partitioning H into subgraphs of H such that any two subgraphs intersect in at most one edge. This decompositions are called G-orthogonal decompositions of H if and only if every subgraph in such decompositions is isomorphic to the graph G. Such decomposition appear in a lot of applications; statistics, information theory, in the theory of experimental design and many others. An approach of constructing orthogonal decompositions of regular graph is introduced here. Application of this approach for constructing tree -- orthogonal decompositions of complete bipartite graph is considered. Further, the use of orthogonal decompositions for designing hamming tree-codes is also discussed along with examples. The study shows that such codes have an efficient properties when are used to detect and correct the errors that may occur during a transmission of data through a network. Furthermore, we present a method for the recursive construction of orthogonal decompositions.