Technology
Researchers Develop Algorithm for Optimal Decision Making Under Heavy-tailed Noisy Rewards
By Adedapo Adesanya
The exploration algorithms for stochastic multi-armed bandits (MABs)–sequential decision-making problems under uncertain environments–typically assume light-tailed distributions for reward noises.
However, real-world datasets often show heavy-tailed noise. In light of this, researchers from Korea propose an algorithm that can achieve minimax optimality (minimum loss under maximum loss scenario) with minimal prior information.
Superior to existing algorithms, the new algorithm has potential applications in autonomous trading and personalized recommendation systems.
In data science, researchers typically deal with data that contain noisy observations. An important problem explored by data scientists in this context is the problem of sequential decision-making. This is commonly known as a “stochastic multi-armed bandit” or (stochastic MAB).
Here, an intelligent agent sequentially explores and selects actions based on noisy rewards under an uncertain environment. Its goal is to minimize cumulative regret–the difference between the maximum reward and the expected reward of selected actions. A smaller regret implies more efficient decision-making.
Most existing studies on stochastic MABs have performed regret analysis under the assumption that the reward noise follows a light-tailed distribution. However, many real-world datasets, in fact, show a heavy-tailed noise distribution.
These include user behavioural pattern data used for developing personalized recommendation systems, stock price data for automatic transaction development, and sensor data for autonomous driving.
In a recent study, Assistant Professor Kyungjae Lee of Chung-Ang University and Assistant Professor Sungbin Lim of the Ulsan Institute of Science and Technology, both in Korea, addressed this issue. In their theoretical analysis, they proved that the existing algorithms for stochastic MABs were sub-optimal for heavy-tailed rewards.
More specifically, the methods employed in these algorithms–robust upper confidence bound (UCB) and adaptively perturbed exploration (APE) with unbounded perturbation–do not guarantee a minimax (minimization of maximum possible loss) optimality.
“Based on this analysis, minimax optimal robust (MR) UCB and APE methods have been proposed. MR-UCB utilizes a tighter confidence bound of robust mean estimators, and MR-APE is its randomized version. It employs bounded perturbation whose scale follows the modified confidence bound in MR-UCB,” explains Dr Lee, speaking of their work, which was published in the IEEE Transactions on Neural Networks and Learning Systems on 14 September 2022.
The researchers next derived gap-dependent and independent upper bounds of the cumulative regret. For both the proposed methods, the latter value matches the lower bound under the heavy-tailed noise assumption, thereby achieving minimax optimality.
Further, the new methods require minimal prior information and depend only on the maximum order of the bounded moment of rewards. In contrast, the existing algorithms require the upper bound of this moment a priori–information that may not be accessible in many real-world problems.
Having established their theoretical framework, the researchers tested their methods by performing simulations under Pareto and Fréchet noises. They found that MR-UCB consistently outperformed other exploration methods and was more robust with an increase in the number of actions under heavy-tailed noise.
Further, the duo verified their approach for real-world data using a cryptocurrency dataset, showing that MR-UCB and MR-APE were beneficial–minimax optimal regret bounds and minimal prior knowledge–in tackling heavy-tailed synthetic and real-world stochastic MAB problems.
“Being vulnerable to heavy-tailed noise, the existing MAB algorithms show poor performance in modelling stock data. They fail to predict big hikes or sudden drops in stock prices, causing huge losses. In contrast, MR-APE can be used in autonomous trading systems with stable expected returns through stock investment,” comments Dr Lee, discussing the potential applications of the present work.
“Additionally, it can be applied to personalized recommendation systems since behavioural data shows heavy-tailed noise. With better predictions of individual behaviour, it is possible to provide better recommendations than conventional methods, which can maximize the advertising revenue,” he concludes.
Choosing between a VPS and a dedicated server can be complex. They run apps and webpages. But they operate differently. Understanding the difference between VPS and dedicated server solutions will help you prevent complications and save money later on. In this text we will explain everything in detail with examples from actual life.
VPS vs Dedicated Server: What Actually Sets Them Apart
One physical machine is divided into multiple virtual servers by a VPS. Through virtualization software, each user receives a portion of resources that are separate from those of other users.
A dedicated server operates in a different manner. One user owns a single physical machine. No neighbors, no sharing, simply complete hardware access.
This is the core of the vps vs dedicated server debate. Shared hardware means lower costs, while full ownership means more raw power. Finding the best vps hosting service often comes down to how well a provider balances performance with fair pricing on shared resources.
| Factor | VPS | Dedicated Server |
| Resource allocation | Shared pool, virtualized | 100% dedicated hardware |
| Performance consistency | Possible noisy neighbor effect | Guaranteed, stable capacity |
| Scalability | Instant resize | Requires hardware upgrade or migration |
| Cost | Lower entry price | Higher fixed cost |
Performance, Cost and Control: Where Each One Wins
In terms of raw performance, dedicated servers are superior. Each gigabyte of RAM and each CPU cycle are part of a single project. There is no competition for resources.
Flexibility is where VPS excels. It takes minutes, not days, to scale up. Pricing stays lower too, since costs get split across multiple users on the same hardware.
Shared hardware limitations rarely cause problems for smaller projects. Providers like Antihost allocate resources fairly, so performance stays steady even during traffic spikes. The gap only really matters once traffic gets heavy and consistent.
The contrast of vps vs virtual machine is also confusing people often. A VPS is a virtual computer in a technical sense, but it’s rented from a hosting company, rather than running on your own hardware.
Matching the Server to the Project: Real Scenarios
A dedicated server is rarely required for a small business website. A VPS can easily manage moderate traffic while maintaining low expenses.
A growing SaaS product usually starts on a VPS and expands as the user base grows. This adaptability is more crucial in the early stages than brute strength.
A database-heavy application benefits from dedicated hardware once query volume reaches a certain level. In this case, the lack of resource sharing and a constant disk speed are essential.
A game server depends on low latency and steady performance. Many game servers run fine on VPS today, especially with modern hardware. As David Heinemeier Hansson put it: “Personal servers have gotten really scarily quick, inefficient, and personal internet connections rival what we connected data centers with just a decade or two ago.” That shift makes VPS a stronger option than it used to be.
Here is a quick breakdown of what typically fits best:
- Small business website: VPS, for cost and simplicity
- Growing SaaS product: VPS, then scale to dedicated later
- Database-heavy app: Dedicated server, for consistent speed
- Game server: VPS, unless player counts get very large
Summary
In every situation, neither choice is superior to the other. Everything impacts the optimal selection, including the scale of the project, traffic patterns, and all growth plans. Scale from what works now when the numbers really demand it.
By Modupe Gbadeyanka
The Executive Vice Chairman of the Nigerian Communications Commission (NCC), Mr Aminu Maida, has reemphasised the need to protect the nation’s telecommunications infrastructure, especially fibre networks, noting that damage to fibre networks carries significant economic consequences.
Speaking virtually at the Association of Telecommunications Companies of Nigeria (ATCON) Critical Conversation Forum on Fibre-to-the-Home (FTTH) in Lagos recently, he described FTTH as a critical enabler of Nigeria’s digital future.
“FTTH is uniquely positioned to meet Nigerians' next phase of data demand. The quality of our broadband will increasingly shape the competitiveness of our businesses, the growth of our digital industry and the opportunities available to our citizens,” the NCC chief stated.
“We must uphold deployment standards. Nigeria needs fibre that is properly installed, properly documented, and properly protected,” Mr Maida further said at the event themed Fibre to the Home in Nigeria: Addressing Challenges, Strengthening Standards and Ensuring Sustainable Deployment.
During a panel discussion titled Policy, Governance and Regulatory Alignment, the Deputy Director of Strategic Business Initiatives at ipNX, Mr Segun Okuneye, highlighted the need for stronger collaboration across the telecommunications ecosystem to unlock the full potential of fibre broadband in Nigeria.
According to him, sustainable fibre deployment extends beyond technology and investment to include policy consistency, stakeholder alignment, infrastructure protection, and shared responsibility.
“Achieving universal fibre connectivity requires more than deploying infrastructure; it requires sustained collaboration between operators, regulators, government agencies and host communities.
“When policies are aligned, deployment standards are consistently enforced, and critical infrastructure is protected, we create an environment where investment thrives and more Nigerians can enjoy reliable, high-speed broadband.
“At ipNX, we remain committed to working with all stakeholders to build resilient digital infrastructure that will support Nigeria’s economic growth for generations to come.”
Earlier in his welcome address, ATCON President, Mr Tony Emoekpere, underscored the strategic importance of FTTH in achieving the country’s broadband penetration targets while calling for greater public awareness around protecting communications infrastructure.
“This forum is critical because Fibre-to-the-Home is the technology that will enable the country to achieve full broadband penetration. We all depend on communication infrastructure, and it must be protected,” he declared.
Drawing a comparison with power infrastructure in the country, he added, “If somebody comes to your neighbourhood to tamper with your transformer or power cables, everybody will come out. The same thing needs to apply for communications infrastructure. When we see people damaging fibre cables, we should raise an alarm.”
By Modupe Gbadeyanka
Thursday, July 23, 2026, provided an opportunity for financial services professionals to converge on Landmark Event Centre, Lagos, to brainstorm on ways to meet the rising customers’ expectations.
The platform used for this purpose was Core by Interswitch. It is part of the company’s broader commitment to strengthening Africa’s digital payments ecosystem by fostering collaboration, knowledge sharing and operational excellence across the financial services value chain.
At the event, participants, numbering over 400, also highlighted the growing importance of operational excellence in sustaining resilient payment infrastructure.
As digital financial services continue to expand across Africa, closer collaboration among financial institutions, fintechs and payment service providers will be essential to improving responsiveness, resolving operational challenges more effectively and delivering consistently reliable customer experiences.
The Executive Vice President for Operations and Technology at Interswitch, Mr Babafemi Ogungbamila, said the forum reflects the company’s belief that exceptional customer experiences are built not only on innovative technology but also on the expertise, collaboration and commitment of the professionals who keep payment systems running every day.
“Every successful digital transaction is powered by professionals whose work often goes unseen but is fundamental to building trust in digital payments. Core by Interswitch was created to recognise their contribution, strengthen collaboration across the industry and create opportunities for shared learning that ultimately benefit financial institutions and the customers they serve.
“As digital payments continue to evolve, investing in the people and processes that power the technology is just as important as investing in the technology itself,” Mr Ogungbamila said.
Beyond recognising the professionals whose work often goes unnoticed, the programme underscored the value of creating stronger connections across the payments ecosystem.
By creating a dedicated platform for knowledge sharing, collaboration and professional development, Core by Interswitch aims to build a more connected community of payments operations professionals equipped to respond to the evolving demands of the digital economy.
