The development of smart contracts remains in its early stages, with significant differences in underlying programming languages and application platforms resulting in a lack of standardization. This lack of standardization increases the susceptibility to vulnerabilities and associated financial losses. To address security vulnerabilities in smart contracts on the Ethereum blockchain platform, this paper proposes a security audit method based on formal verification. The method integrates an input module, static analysis module, formal verification module, analog execution module, and report and recommendation module, which can accurately discover the security vulnerabilities and logical flaws of smart contracts through formal verification and other analysis techniques, thus realizing correctness detection. During the experiment, the method detects 8 types of common vulnerabilities in 148 smart contracts and marks 21 smart contracts with vulnerabilities. After manual review and analysis, it is found that 17 of these 21 marked smart contracts do have security vulnerabilities. The experimental results show that the proposed method can accurately detect security vulnerabilities and logic flaws in smart contracts through formal verification and other analysis techniques before smart contracts are deployed, thus significantly improving the security of smart contracts and reducing the economic losses that may be caused by code defects.
Super-instructions are a crucial optimization method for interpreters, as they combine multiple basic instructions into single specialized operations. The optimization technique reduces dispatch overhead and enables further optimizations in the synthesized operation code for a super-instruction. However, due to combinatorial explosion, identifying super-instructions is a complex selection problem. This paper presents a novel approach for the automated synthesis of super-instructions using a combination of offline dictionary-based compression algorithms and greedy heuristics. Our method addresses the common issue of overlap between super-instructions, which previous approaches often overlook. Additionally, we introduce a meta-compiler for the Ethereum Virtual Machine (EVM) that automatically generates a new interpreter incorporating the super-instructions. The super-instructions generated with our approach result in an 8.45% speedup for the interpreter component of the EVM.
Blockchain consensus mechanisms play a critical role in ensuring the security, decentralization, and integrity of distributed networks. As blockchain technology expands beyond cryptocurrencies into broader applications such as supply chain management and healthcare, the importance of efficient and scalable consensus algorithms has grown significantly. This study provides a comprehensive bibliometric analysis of blockchain and consensus mechanism research from 2014 to 2024, using tools such as VOSviewer and R’s Bibliometrix package. The analysis traces the evolution from foundational mechanisms like Proof of ork (PoW) to more advanced models such as Proof of Stake (PoS) and Byzantine Fault Tolerance (BFT), with particular emphasis on Ethereum’s “The Merge” in 2022, which marked the historic shift from PoW to PoS. Key findings highlight emerging themes, including scalability, security, and the integration of blockchain with state-of-the-art technologies like artificial intelligence (AI), the Internet of Things (IoT), and energy trading. The study also identifies influential authors, institutions, and countries, emphasizing the collaborative and interdisciplinary nature of blockchain research. Through thematic analysis, this review uncovers the challenges and opportunities in decentralized systems, underscoring the need for continued innovation in consensus mechanisms to address efficiency, sustainability, scalability, and privacy concerns. These insights offer a valuable foundation for future research aimed at advancing blockchain technology across various industries.
Ethereum, as a representative of Web3, adopts a novel framework called Proposer Builder Separation (PBS) to prevent the centralization of block profits in the hands of institutional Ethereum stakers. Introducing builders to generate blocks based on public transactions, PBS aims to ensure that block profits are distributed among all stakers. Through the auction among builders, only one will win the block in each slot. Ideally, the equilibrium strategy of builders under public information would lead them to bid all block profits. However, builders are now capable of extracting profits from private order flows. In this paper, we explore the effect of PBS with private order flows. Specifically, we propose the asymmetry auction model of MEV-Boost auction. Moreover, we conduct empirical study on Ethereum blocks from January 2023 to May 2024. Our analysis indicates that private order flows contribute to 54.59% of the block value, indicating that different builders will build blocks with different valuations. Interestingly, we find that builders with more private order flows (i.e., higher block valuations) are more likely to win the block, while retain larger proportion of profits. In return, such builders will further attract more private order flows, resulting in a monopolistic market gradually. Our findings reveal that PBS in current stage is unable to balance the profit distribution, which just transits the centralization of block profits from institutional stakers to the monopolistic builder.
Background. A smart contract is a computer program enclosing the terms of a legal agreement between two or more parties which is automatically verified and executed via a computer network called blockchain. Once a smart contract transaction is completed the blockchain is updated and the transaction cannot be changed anymore. This implies that any error codified in the smart contract program cannot be rectified. Therefore, it is of vital importance that developers of smart contracts properly exploit error handling to prevent issues during and after the contract execution. Existing programming languages for smart contracts, support developers in this task by providing a set of Error Handling (EH) features. However, it is unclear the extent to which developers effectively use EH in practice. Aims. Our work aims to fill this gap by empirically investigating the state of practice on the adoption of EH features of one of the most popular programming languages for smart contracts, namely Solidity. Method. We empirically analyse the usage of EH features in 283K unique open-source Solidity smart contracts for the Ethereum blockchain. Results. Our analysis of the documentation of the different versions of Solidity coupled with the empirical evaluation of the EH uses and misuses found in real-word smart contracts, indicate that, among other things, Solidity EH features have been changing frequently across versions, and that the adoption of most of the Solidity EH features has been limited in practice. However, we observe an upward trend in the usage of the require EH feature, which is specifically designed for smart contract development. Conclusions. The insights from our study could help developers improve their EH practice as well as designers of smart contract programming languages to equip their language with appropriate EH features.
Andrey L. Bulgakov, Anna V. Aleshina, Sergey D. Smirnov, Alexey D. Demidov · 6 authors
This article addresses the issues of scalability and security in blockchain networks, with a focus on sharding algorithms and decentralized data storage. Key challenges include the low throughput and high transaction latency in public networks such as Bitcoin and Ethereum. Sharding is examined as a method to enhance performance through data distribution, but it raises concerns regarding node management and reliability. Sharding schemes, such as Elastico, OmniLedger, Pyramid, RepChain, and SSchain, are analyzed, each presenting its own advantages and drawbacks. Alternative architectures like Directed Acyclic Graphs (DAGs) demonstrate potential for improved scalability but require further refinement to ensure decentralization and security. Protocols such as Brokerchain, Meepo, AHL, Benzene, and CycLedger offer unique approaches to addressing performance and transaction consistency issues. This article emphasizes the need for a comprehensive approach, including dynamic sharding, multi-level consensus, and inter-shard coordination. Additionally, a conceptual model is proposed that incorporates the sharding of transactions, states, and networks, which enables greater scalability and efficiency.
Krzysztof Gogol, Manvir Schneider, Tessone, Claudio, Livshits, Benjamin
Layer-2 (L2) blockchains inherit Ethereums security guarantees while reducing gas fees. As a result, they are gaining traction among traders at Automated Market Makers (AMMs), sparking debate over whether they contribute to liquidity fragmentation of Ethereum. Our research suggests that such fragmentation is not currently occurring. However, it could emerge in the future, particularly if Liquidity Providers (LPs) recognize the higher returns available on L2s. Using Lagrangian optimization, we develop a model for optimal liquidity allocation across AMMs on Ethereum and its L2s, using staking as a benchmark. We show that, in equilibrium, AMM liquidity provision returns converge to this reference rate. Additionally, we measure the elasticity of trading volume with respect to Total Value Locked (TVL) in AMMs and find that, on well-established blockchains, an increase in TVL does not necessarily lead to higher trading volume. Finally, our empirical findings reveal that Ethereums liquidity pools are oversubscribed compared to those on L2s and often yield lower returns than staking Ether. LPs could maximize their rewards by reallocating more than two-thirds of their liquidity to L2s and staking.
Pohsun Feng, Ziqian Bi, Yan, Lawrence K. Q., Yizhu Wen · 17 authors
A detailed exploration of blockchain technology and its applications across various fields is provided, beginning with an introduction to cryptography fundamentals, including symmetric and asymmetric encryption, and their roles in ensuring security and trust within blockchain systems. The structure and mechanics of Bitcoin and Ethereum are then examined, covering topics such as proof-of-work, proof-of-stake, and smart contracts. Practical applications of blockchain in industries like decentralized finance (DeFi), supply chain management, and identity authentication are highlighted. The discussion also extends to consensus mechanisms and scalability challenges in blockchain, offering insights into emerging technologies like Layer 2 solutions and cross-chain interoperability. The current state of academic research on blockchain and its potential future developments are also addressed.
Penelitian ini mengembangkan aplikasi terdesentralisasi (DApp) untuk manajemen sertifikat digital menggunakan Non-Fungible Token (NFT) berbasis standar ERC-721 di jaringan Ethereum. Aplikasi ini dirancang untuk meningkatkan keamanan, dan transparansi dalam pembuatan, pengelolaan, serta verifikasi sertifikat digital. Hasil penelitian menunjukan bahwa penggunaan teknologi blockchain memberikan jaminan bahwa setiap sertifikat yang diterbitkan tidak hanya dapat dilacak dan diverifikasi secara publik, tetapi juga tidak dapat diubah atau dimanipulasi setelah diterbitkan. Hal ini membuat sistem lebih aman dibandingkan dengan metode tradisional. Implementasi standar ERC-721 memungkinkan setiap sertifikat digital yang diterbitkan dalam bentuk NFT memiliki identitas unik yang tidak dapat diduplikasi atau dipalsukan. Selain itu, teknologi ini juga memungkinkan pemilik sertifikat untuk memiliki bukti kepemilikan yang aman dan dapat diverifikasi oleh pihak ketiga. Pengembangan dan pengujian smart contract yang ditulis dalam bahasa pemrograman Solidity pada platform Ethereum juga berhasil membuktikan bahwa smart contract yang dibuat berfungsi dengan baik dalam berbagai aspek seperti penciptaan, transfer, verifikasi, dan penghapusan sertifikat. Smart contract ini menunjukkan keamanan sesuai dengan spesifikasi yang diharapkan, menjadikannya solusi inovatif untuk manajemen sertifikat digital. Kata Kunci - Blockchain, Ethereum, DApp, Sertifikat Digital, NFT, ERC-721.
The United Nations’ sustainable development goals (SDGs) present a global challenge that demands innovative solutions. Combining emerging technologies can be a transformative approach to achieving these goals and overcoming associated challenges. Blockchain provides a secure and transparent platform, while big data and data mining enable the analysis of vast datasets to identify critical areas and measure progress. Additionally, blockchain facilitates secure knowledge exchange among stakeholders through knowledge sharing and management. Recent research demonstrates the effectiveness of blockchain in implementing SDGs. Our study explores the benefits of various technologies and proposes a hybrid model based on Ethereum. This model leverages additional technologies to enhance performance, increase transparency, and reduce gas fees. This combination empowers informed decision-making and accelerates progress towards a sustainable future.
Over the past years, cryptocurrencies have experienced a surge in popularity within the financial markets. As of today, besides being considered for investment purposes, they also serve as a widely accepted form of currency for everyday transactions. Due to the intricate characteristics of financial markets and their dependence on various factors to determine the prices of stocks and assets, the ability to predict such prices is crucial to make investment choices, especially in terms of cryptocurrencies. In this work, a comparative analysis on the suitability of Deep Learning (DL) algorithms (effective for time series forecasting) in predicting the price of three cryptocurrencies (namely Bitcoin, BTC; Ethereum, ETH; and Ripple, XRP) is assessed in terms of both short-term and long-term prediction accuracy. The results, evaluated using Root Mean Square Error (RMSE), Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), and coefficient of determination (denoted as \(R^{2}\) ), reveal that: Transformer is generally more effective for short-term forecasts and also performs well for long-term predictions; Convolutional Neural Network-Recurrent Neural Network (CNN-RNN) demonstrates the lowest complexity in terms of number of Multiply and ACcumulate (MAC) operations; SimpleRNN has the fewest parameters and the smallest FLASH memory requirement. Overall, CNN-Gated Recurrent Unit (CNN-GRU) provides the best joint accuracy-complexity for predicting BTC and ETH prices, whereas CNN-RNN yields superior results for XRP price prediction.
Ken Lew, Arijet Sarker, Simeon Wuthier, Jinoh Kim · 6 authors
Computing and networking are increasingly implemented in software. We design and build a software build assurance scheme detecting if there have been injections or modifications in the various steps in the software supply chain, including the source code, compiling, and distribution. Building on the reproducible build and software bill of materials (SBOM), our work is distinguished from previous research in assuring multiple software artifacts across the software supply chain. Reproducible build, in particular, enables our scheme, as our scheme requires the software materials/artifacts to be consistent across machines with the same operating system/specifications. Furthermore, we use blockchain to deliver the proof reference, which enables our scheme to be distributed so that the assurance beneficiary and verifier are the same, i.e., the node downloading the software verifies its own materials, artifacts, and outputs. Blockchain also significantly improves the assurance efficiency. We first describe and explain our scheme using abstraction and then implement our scheme to assure Ethereum as the target software to provide concrete proof-of-concept implementation, validation, and experimental analyses. Our scheme enables more significant performance gains than relying on a centralized server thanks to the use of blockchain (e.g., two to three orders of magnitude quicker in verification) and adds small overheads (e.g., generating and verifying proof have an overhead of approximately one second, which is two orders of magnitude smaller than the software download or build processes).
Sushanth Sreenivasamurthy Manakhari, Ajinkya P. Jadhav, Twinkle Paraye, Anurag Gate
In the evolving landscape of digital data management, blockchain technology emerges as a transformative force, particularly through its implementation within Ethereum. This paper delves into the role of Ethereum in enhancing data accessibility across distributed file systems. By leveraging the power of smart contracts, Ethereum introduces a level of automation and reliability previously unattainable in traditional systems. The integration of Ethereum with decentralized storage solutions like the Inter Planetary File System (IPFS) facilitates not only more transparent and efficient access to data but also augments security and trustworthiness. We explore the technical mechanisms by which Ethereum smart contracts automate data operations and how these interactions enhance system performance and user experience. Furthermore, the paper discusses the potential challenges and solutions associated with integrating blockchain technologies into existing data systems, thereby providing insights into their future implications for the global data economy. The findings indicate that Ethereum substantially increases accessibility, reduces operational bottlenecks, and could pave the way for new data governance models that are secure, efficient, and scalable.
Rahul Ganpatrao Sonkamble, Anupkumar M. Bongale, Shraddha Phansalkar, Deepak Dharrao
An Electronic Health Record (EHR) store essential and sensitive patient's medical information. Since health information is highly confidential data, it should be accessible with the consent of the patient. Blockchain based EHR management system offers improvised privacy and patient-centric approach. EHR management systems are available with multiple blockchain platforms. Generally, EHRs are maintained at several independent blockchain platforms. EHR management systems should be capable of securely exchange data on cross platform blockchain network. The interoperability in such blockchain platforms should facilitate seamless cross-chain interaction and information exchange. This article proposes a method that facilitates secure EHR exchange on Ethereum and Hyperledger fabric network using hepatitis dataset. The key contributions of the proposed method include:•Hash lock based interoperable cross-chain method for EHR exchange across Ethereum and Hyperledger fabric.•Additional security to the EHR is ensured by partitioning EHR as on-chain (blockchain platform) and off-chain InterPlanetary File System (IPFS)•Secure Password Authentication-Based Key Exchange (SPAKE) based session management for EHR exchange across two parties.The proposed patient centric method is validated to ensures the successful exchange of patient EHR across Ethereum and Hyperledger fabric.
The paper proposes and implements a methodology to fit a seven-parameter Generalized Tempered Stable (GTS) distribution to financial data. The nonexistence of the mathematical expression of the GTS probability density function makes the maximum likelihood estimation (MLE) inadequate for providing parameter estimations. Based on the function characteristic and the fractional Fourier transform (FRFT), we provide a comprehensive approach to circumvent the problem and yield a good parameter estimation of the GTS probability. The methodology was applied to fit two heavily tailed data (Bitcoin and Ethereum returns) and two peaked data (S\&P 500 and SPY ETF returns). For each index, the estimation results show that the six-parameter estimations are statistically significant except for the local parameter, $μ$. The goodness-of-fit was assessed through Kolmogorov-Smirnov, Anderson-Darling, and Pearson's chi-squared statistics. While the two-parameter geometric Brownian motion (GBM) hypothesis is always rejected, the GTS distribution fits significantly with a very high p-value; and outperforms the Kobol, Carr-Geman-Madan-Yor, and Bilateral Gamma distributions.
Kasturi Routray, Abhiram Manikonda, Padmalochan Bera
In the age of technological advancement, collaborative e-healthcare emerges as a transformative system eliminating traditional location and accessibility barriers in healthcare services. Here, searchable encryption (SE) plays a key role in enabling healthcare providers to outsource encrypted medical data and search services to third parties like cloud servers, thereby reducing storage and management expenses. This intermediary approach poses challenges of single-point failure, privacy breaches, and potentially untrustworthy results. State-of-the-art public key-based SE methods use a cloud-assisted architecture that doesn’t support reliable and practical searches with fine-grained permissions. Also, such systems require additional support to address potential privacy leakages and ensure data availability at the storage server. To address these concerns, we propose a blockchain-assisted efficient and secure keyword search (BESKS) scheme to enforce fine-grained keyword search privilege control while achieving practical search complexity. Our scheme employs a ciphertext-policy attribute-based keyword search mechanism where keywords are encrypted using expressive access policies to build an inverted index structure. The encrypted indexes are stored on the blockchain while encrypted medical documents are stored on InterPlanetary File System (IPFS) nodes to enhance availability and ensure the reliability and scalability of our approach. Our scheme utilizes blockchain-based smart contract for efficient, secure search operations and ensures financial fairness in fine-grained searches. Search tokens are generated based on user attributes and query keywords to facilitate private searches on-chain. To enhance the search process, our secure index enables exact match for a query keyword in constant time to ensure expensive authorization operations are performed only once. Theoretical analysis suggests that our BESKS is more efficient and secure than state-of-the-art schemes. Prototype implementation results on the Ethereum blockchain network further validate its feasibility for real-world applications, demonstrating the scheme’s practical applicability in collaborative e-healthcare systems.
Ruben Hias, Weihong Wang, Jan Vanhoof, Tom Van Cutsem
The perpetual growth of data stored on popular blockchains such as Ethereum leads to significant scalability challenges and substantial storage costs for operators of full nodes. Increasing costs may lead to fewer independently operated nodes in the network, which poses risks to decentralization (and hence network security), but also pushes decentralized app developers towards centrally hosted API services. This paper introduces a new protocol that allows validator nodes to participate in a blockchain network without the need to store the full state of the network on each node. The key idea is to use the blockchain network as both a replicated state machine and as a distributed storage system. By distributing states across nodes and enabling efficient data retrieval through a Kademlia-inspired routing protocol, we reduce storage costs for validators. Cryptographic proofs (such as Merkle proofs) are used to allow nodes to verify data stored by other nodes without having to trust those nodes directly. While the protocol trades off data storage for increased network bandwidth, we show how gossiping and caching can minimize the increased bandwidth needs. To validate our state sharing protocol, we conduct an extensive quantitative analysis of Ethereum's data storage and data access patterns. Our findings indicate that while our protocol significantly lowers storage needs, it comes with an increased bandwidth usage ranging from 1.5 MB to 5 MB per block, translating to an additional monthly bandwidth of 319 GB to 1,065 GB. Despite this, the size remains small enough such that it can be passed to all nodes and validated within Ethereum's 12-second block validation window. Further analysis shows that Merkle proofs are the most significant contributor to the additional bandwidth. To address this concern, we also analyze the impact of switching to the more space-efficient Verkle Proofs.
Accountability refers to a relationship of responsibility, answerability, and enforceability between individuals and groups. In contrast to traditional institutions that rely on enforcement of accountability through traditional legal frameworks, blockchain systems rely on the “rule of code”, i.e. the operation, governance, and transactions on a blockchain are governed by pre-written, transparent, and immutable rules that are expressed in software code. By empirically examining the case of the Ethereum blockchain and the Lido “liquid” staking services protocol, this paper analyses the formalisation of accountability mechanisms between protocols to ensure that Lido’s proportionate share of staked ETH on the network does not pose a risk to the security and stability of Ethereum. The findings of this paper are threefold: (1) accountability on a blockchain is achieved through the implementation of checks and balances institutionalised via technological protocols ("on-chain accountability"); (2) accountability requires trade-offs, meaning that giving accountability to one type of stakeholders might actually reduce the accountability of the system for another category of stakeholder; and (3) end users of the blockchain are consumers of accountability, rather than influential participants in producing it. This research underscores the complex interplay of technical and governance considerations in ensuring accountability within blockchain systems, offering insights into the broader implications of on-chain accountability for stakeholders across blockchain ecosystems.
Adi Prasetyo, Nurdin Nurdin, Hafizh Al Kautsar Aidilof
Cryptocurrency has emerged as a prominent digital asset over the past decade, but its high price volatility presents significant challenges for investors. This study evaluates and compares the effectiveness of the Triple Exponential Smoothing (TES) and Autoregressive Integrated Moving Average (ARIMA) methods in forecasting the prices of five major cryptocurrencies: Bitcoin (BTC), Ethereum (ETH), Binance Coin (BNB), Solana (SOL), and Ripple (XRP). TES models trends and seasonality in time series data, while ARIMA captures autoregressive patterns and moving averages. The dataset is split into 80% for training and 20% for testing, with performance evaluated using Mean Absolute Percentage Error (MAPE) and Root Mean Squared Error (RMSE). TES outperforms ARIMA in predicting Bitcoin and Binance Coin, achieving MAPE values of 10.38% and 13.81%, and RMSE values of 3,985.55 and 41.28, respectively. However, ARIMA shows better performance for Ethereum, Solana, and Ripple, with MAPE ranging from 8.78% to 32.84% and RMSE between 0.08 and 204.59. Notably, Ethereum has the lowest MAPE at 8.78%, while Ripple exhibits the smallest RMSE at 0.08. These findings suggest that TES is more suitable for cryptocurrencies with relatively stable price patterns, while ARIMA is better adapted to forecasting highly volatile assets. This research underscores the importance of selecting forecasting models based on the specific characteristics of each cryptocurrency
Mohamed Fartitchou, Ismail Lamaakal, Khalid El Makkaoui, Zakaria El Allali · 5 authors
Morocco's Vision 2030, known as Maroc Digital 2030, aims to position the country as a regional leader in digital technology by boosting digital infrastructure, fostering innovation, and advancing digital skills. Complementing this initiative, the Pacte ESRI 2030 strategy, launched in 2023, seeks to transform the higher education, research, and innovation sectors by integrating state-of-the-art digital technologies. In alignment with these national strategies, this paper introduces BlockMEDC, a blockchain-based system for securing and managing Moroccan educational digital certificates. Leveraging Ethereum smart contracts and the InterPlanetary File System, BlockMEDC automates the issuance, management, and verification of academic credentials across Moroccan universities. The proposed system addresses key issues such as document authenticity, manual verification, and lack of interoperability, delivering a secure, transparent, and cost-effective solution that aligns with Morocco's digital transformation goals for the education sector.
There is a huge demand to ensure the compliance of smart contracts listed on blockchain platforms to safety and economic standards described in natural languages. Today, manual efforts in the form of auditing are commonly used to achieve this goal. ML-based automated techniques have the promise to alleviate human efforts and the resulting monetary costs. However, unlike other domains where ML techniques have had huge successes, no systematic ML techniques have been proposed or applied to smart contract auditing. We present SC-Bench, the first dataset for automated smart-contract auditing research. SC-Bench consists of 5,377 real-world smart contracts running on Ethereum, a widely used blockchain platform, and 15,975 violations of standards on Ehereum called ERCs. Out of these violations, 139 are real violations programmers made. The remaining are errors systematically injected by us to reflect the violations of different ERC rules. We evaluate SC-Bench using GPT-4 by prompting it with both the contracts and ERC rules. In addition, we manually identify each violated rule and the corresponding code site (i.e., oracle) and prompt GPT-4 with the information asking for a True-or-False question. Our results show that without the oracle, GPT-4 can only detect 0.9% violations, and with the oracle, it detects 22.9% violations. These results show the potential room for improvement in ML-based techniques for smart-contract auditing.
Kostas Giannopoulos, Ramzi Nekhili, Christos Christodoulou-Volos
Understanding the density of possible prices in one-minute intervals provides traders, investors, and financial institutions with the data necessary for making informed decisions, managing risk, optimizing trading strategies, and enhancing the overall efficiency of the cryptocurrency market. While high accuracy is critical for researchers and investors, market nonlinearity and hidden dependencies pose challenges. In this study, the filtered historical simulation is used to generate pathways for the next hour on the one-minute step for Bitcoin and Ethereum quotes. The innovations in the simulation are standardized historical returns resampled with the method of block bootstrapping, which helps to capture any hidden dependencies in the residuals of a conditional parameterization in the mean and variance. Ordinary bootstrapping requires the feed innovations to be free of any dependencies. To deal with complex data structures and dependencies found in ultra-high-frequency data, this study employs block bootstrap to resample contiguous segments, thereby preserving the sequential dependencies and sectoral clustering within the market. These techniques enhance decision-making and risk measures in investment strategies despite the complexities inherent in financial data. This offers a new dimension in measuring the market risk of cryptocurrency prices and can help market participants price these assets, as well as improve the timing of their entry and exit trades.
Oct 8, 2024·4th International Conference on AI-ML Systems (AIMLSystems 2024), October 08-11, 2024, Baton Rouge, LA, USA. ACM, New York, NY, USA, 8 pages
Francesco Puoti, Fabrizio Pittorino, Manuel Roveri
This paper offers a thorough examination of the univariate predictability in cryptocurrency time-series. By exploiting a combination of complexity measure and model predictions we explore the cryptocurrencies time-series forecasting task focusing on the exchange rate in USD of Litecoin, Binance Coin, Bitcoin, Ethereum, and XRP. On one hand, to assess the complexity and the randomness of these time-series, a comparative analysis has been performed using Brownian and colored noises as a benchmark. The results obtained from the Complexity-Entropy causality plane and power density spectrum analysis reveal that cryptocurrency time-series exhibit characteristics closely resembling those of Brownian noise when analyzed in a univariate context. On the other hand, the application of a wide range of statistical, machine and deep learning models for time-series forecasting demonstrates the low predictability of cryptocurrencies. Notably, our analysis reveals that simpler models such as Naive models consistently outperform the more complex machine and deep learning ones in terms of forecasting accuracy across different forecast horizons and time windows. The combined study of complexity and forecasting accuracies highlights the difficulty of predicting the cryptocurrency market. These findings provide valuable insights into the inherent characteristics of the cryptocurrency data and highlight the need to reassess the challenges associated with predicting cryptocurrency's price movements.
Shelly Grossman, John Toman, Alexander Bakst, Sameer Arora · 6 authors
SMT-based verification of low-level code requires modeling and reasoning about memory operations. Prior work has shown that optimizing memory representations is beneficial for scaling verification—pointer analysis, for example can be used to split memory into disjoint regions leading to faster SMT solving. However, these techniques are mostly designed for C and C++ programs with explicit operations for memory allocation which are not present in all languages. For instance, on the Ethereum virtual machine, memory is simply a monolithic array of bytes which can be freely accessed by Ethereum bytecode, and there is no allocation primitive. In this paper, we present a memory splitting transformation guided by a conservative memory analysis for Ethereum bytecode generated by the Solidity compiler. The analysis consists of two phases: recovering memory allocation and memory regions, followed by a pointer analysis. The goal of the analysis is to enable memory splitting which in turn speeds up verification. We have implemented both the analysis and the memory splitting transformation as part of a verification tool, CertoraProver, and show that the transformation speeds up SMT solving by up to 120× and additionally mitigates 16 timeouts when used on 229 real-world smart contract verification tasks.