Database

Open Risk White Paper 20: Connecting the Dots: Towards a Graph Calculus for Decentralized Social Networks

We develop graph representations of decentralized (heterogeneous) Social Web networks. We build primarily on the machinery of multilayer networks with their associated tensor representations.

We expand on the specialized subclass of so-called layer-disjoint networks as they offer powerful tools for modeling complex online interactions of Actors within distinct Communities. We focus on the quantitative metrics and tools that can be expressed using such a framework, starting with basic building blocks and establishing the practical correspondence between adjacency tensors and supra-adjacency matrices, culminating with a discussion of the construction and use of tensor graph Laplacians.

These tools can on the one hand help ex-post empirical (statistical) work in analyzing the characteristics of current decentralized networks, on the other hand they enable ex-ante simulation and quantification of heterogeneous network properties and behavior.

The standard description of financial reporting almost entirely avoids mathematical formulation (variables, equations and using abstraction as a means to step back from less relevant details). While historically there have been efforts to describe the underlying accounting systems in more rigorous language (see ¹, ²), the same does not apply to the higher level of published financial statements. The primary exception is, of-course, the famous balance sheet equation, which, while fundamental, does not remotely cover the richness of of the financial reporting machinery. Our objective in this post is to express the typical financial statements more concisely: using symbolic mathematical notation that substantially captures their numerical information content and the constraints being satisfied.

Open Risk White Paper 19: Connecting the Dots: Accounting Graphs for Double and Quadruple-Entry Bookkeeping

We develop the concept of an accounting graph as an intuitive and flexible tool that can faithfully represent widely used accounting concepts. More specifically, a weighted directed multigraph representation is applied to model standard double-entry bookkeeping (DEB) of individual accounting entities but extended to also provide a consistent accounting graph for larger economic networks that feature multiple transacting entities (so-called quadruple-entry accounting). We illustrate the concepts with stylized accounting examples. Such accounting graphs are promising both as educational tools and towards the application of computational tools on accounting data.

Recap of Part 1 of the Matrix-to-JSON Post Series

In the first installment of this series, Part 1 we discussed the motivation behind representing and serializing matrices as JSON objects. We defined relevant concepts and in particular the concept of unrolling the matrix into a one-dimensional array and the notion of Column and Row Major orders. We outlined some use cases of interest and initiated a benchmarking exercise that looks into various R and Python JSON serialization utilities (available at the matrix2json repository).

Open Risk White Paper 15: Tensor Representations of ActivityPub Networks

In this third Open Risk White Paper on Connecting the Dots we explore representations of online communication networks that are organized according to the ActivityPub protocol. We discuss the main relevant features of the protocol and the broader application ecosystem around it that shapes emerging online network topologies. We develop a stylized description of ActivityPub compliant networks as a mathematical multilayer network. Tensor representations of such complex graphs generalize the more familiar matrix algebra tools and can be useful in various ways: On the one hand they help empirical work in analyzing the characteristics of such networks, on the other they enable simulating and exploring network behavior.

What are ActivityPub Networks?

ActivityPub is a technical specification towards decentralized (more precisely, federated) social networking (termed the Fediverse) based upon the exchange of ActivityStreams messages that follow the Activity Vocabulary. The ActivityPub proposal has been standardized and published by the W3C and has motivated the design of several federated social networking systems.

Open Risk White Paper 14: Integrated energy accounting using relational databases

In this Open Risk White Paper we demonstrate a concrete implementation of an integrated energy accounting framework using relational database technologies. The framework enables accounting of non-financial disclosures (such as the physical and embodied energy footprints of economic transactions) while enforcing the familiar double-entry balance constraints used to produce conventional (monetary) accounts and financial statements. In addition, it allows enforcing constraints associated with the flow and transformations of energy that can happen inside the organizational perimeter.

Open Risk White Paper 13: Federated Credit Systems, Part II: Techniques for Federated Data Analysis

In this Open Risk White Paper, the second of series focusing on Federated Credit Systems, we explore techniques for federated credit data analysis. Building on the first paper where we outlined the overall architecture, essential actors and information flows underlying various business models of credit provision, in this step we focus on the enabling arrangements and techniques for building Federated Credit Data Systems and enabling Federated Analysis.

Course Objective

Digging into the meaning of credit data collections, the logic that binds them together towards understanding what they can be used for and what limitations and issues they may be affected by, this new course in the Credit Portfolio Management category explores a new angle to look at an old practice.

Course Objective

Digging into the meaning of credit data collections, the logic that binds them together towards understanding what they can be used for and what limitations and issues they may be affected by, this new course in the Credit Portfolio Management category explores a new angle to look at an old practice.

Integrated Energy Accounting is keeping track and reporting on an entity’s detailed energy footprint (primary inputs, transformations and waste generation) not as an addendum to financial accounting and reporting but as a deeply-linked extension that is subject to the same level of rigor.

Open Risk White Paper 12: Deep-Linking Financial and Energy Accounting

We develop a conceptual framework for integrated accounting that produces (where possible) non-financial disclosures subject to the same double-entry balance constraints as those used to produce conventional financial statements and automatically ensures any additional conservation laws are satisfied. We identify the key ingredients required for such a rigorous integrated accounting framework, in terms of concepts, postulates and design choices. Our focus and concrete use case is built around energy accounting, keeping track on an entity’s detailed energy footprint (primary inputs, transformations and waste generation) as an extension of its standard financial accounting and reporting. The central tool is the use of multidimensional double-entry bookkeeping which tracks quantitative information characterizing economic objects beyond their monetary values. This choice ensures the enforcement of both classic balance constraints and any applicable energy conservation laws. Further tools and techniques concern the aggregation and reporting of dual (monetary and physical) dimensions of an entity’s accounting state. The framework is documented using mathematical notation.

Motivation and Objective

Representing a Matrix as a JSON object is a task that appears in many modern data science contexts, in particular when one wants to exchange matrix data online in a portable manner. There is no universally agreed way to achieve this task and various options are available depending on the matrix data characteristics and the programming tools and computational environment one has available.

Summary

In this short course we explore how some programming languages, data formats, database API’s and web frameworks handle hierarchical classes.

Content

Object-oriented programming and techniques (OOP) such as using classes and inheritance are common in many application programming environments but alas don’t “travel well” outside computer memory. The potentially intricate relationships of objects (both the data they hold and the meaning and possible uses of the data) are not easy to transfer (except of-course by full replication of code and data). Hence when considering data science tasks and objectives that involving exchange of data, the transition from object hierarchies that live inside memory, to data structures that can be exchanged with another computer is not straightforward.

Open Risk White Paper 9: Federated Credit Systems, Part I: Unbundling The Credit Provision Business Model

In this (the first of series of three) white paper, we introduce and explore the concept of federated credit systems. We review the rapidly developing fields of Federated Analysis and Federated Learning as already actively studied in the domains of medicine and consumer computing devices. This forms the backdrop for understanding the potential and challenges of applying similar concepts in finance and more particular credit provision. The context of modern banking is substantially different from the above-mentioned use cases. Understanding and shaping federated information systems to cater to its unique features and constraints (key added value, competitive landscape, regulatory frameworks) will help accelerate the adoption of new designs. Towards that purpose we construct a framework that conceptually unbundles the complex operation that is modern credit provision. We introduce a number of fundamental business entities (subunits) and their associated functions and discuss the underlying business models. We discuss, in particular, how and why they exchange data and metrics and the key risk management challenges of each. Finally, we sketch current architectures for credit information sharing with an overture to the new possibilities opening up with federation architectures.

Making Open Risk Data easier

In an earlier blog post we discussed the promise of Open Risk Data and how the widespread availability of good information that is relevant for risk management can substantially help mitigate diverse risks.

The list of Open Risk Data providers, particularly from public sector, keeps increasing and we are aiming to document all available datasets in the dedicated page of the Open Risk Manual.

Open Risk White Paper 8: Connecting the Dots, Economic Networks as Property Graphs

We develop a quantitative framework that approaches economic networks from the point of view of contractual relationships between agents (and the interdependencies those generate). The representation of agent properties, transactions and contracts is done in the context of a property graph. A typical use case for the proposed framework is the study of credit networks.

Accounting probably would not count among the more glamorous of professions. The reasons for that status and whether it is justified are beyond the scope of this brief commentary.

What is interesting to note, though, is that the relative attractiveness of accounting is arguably improving, driven by a number of systemic societal developments:

What can Inka Quipus teach us about data management

If, as it is most probable, you are a typical person, chances are that your knowledge of ancient Peruvian culture is a bit rusty!

Maybe you have some vague high-school memories of an extensive but somewhat “backward” empire (as seen by the then European peoples) that was conquered and then asset-stripped by a handful of aggressive Spanish conquistadors.

Or maybe your best preserved memory is the excitement of reading von Daniken’s rampant speculations about the Nazca lines and ancient extraterrestrial spaceports. But unless it happened that at some point later in life you heard about the work of Prof. Urton and his collaborators, most likely you have no idea what an Incan Quipu is (see image).