Hans Friedrich Witschel

FHNW University of Applied Sciences and Arts | FHNW · School of Business

Choosing courses at the beginning of each semester is a complex decision that affects students' future careers and academic performance , especially when given the freedom to choose. Among other factors , the expected grade at the end of the semester and/or the expected ability to successfully complete a course plays an important role in course sel...

Background The use of smartphone apps in cancer patients undergoing systemic treatment can promote the early detection of symptoms and therapy side effects and may be supported by machine learning (ML) for timely adaptation of therapies and reduction of adverse events and unplanned admissions. Objective We aimed to create an Early Warning System (...

This study delves into the application of large language models (LLMs), such as ChatGPT-4, for the automated evaluation of student essays, with a focus on a case study conducted at the Swiss Institute of Business Administration. It explores the effectiveness of LLMs in assessing German-language student transfer assignments, and contrasts their perf...

This position paper presents a novel approach of semantic verification in Large Language Model-based Retrieval Augmented Generation (LLM-RAG) systems, focusing on the critical need for factually accurate information dissemination during public debates, especially prior to plebiscites e.g. in direct democracies, particularly in the context of Switze...

We propose conversational agents as a means to simulate expert interviews, integrated into a simulational learning environment: ChEdventure. Designing and developing conversational agents using the existing tools and frameworks requires technical knowledge and a considerable learning curve. Recently, LLMs are being leveraged for their adaptability...

BACKGROUND Recently the use of smartphone apps has been implemented in clinical trials with cancer patients undergoing systemic treatment. This approach has demonstrated the feasibility of those apps in the early detection of symptoms and therapy side effects. Early detection has the positive effects of (a) enabling the timely adaption of current t...

Besides the typical applications of recommender systems in B2C scenarios such as movie or shopping platforms, there is a rising interest in transforming the human-driven advice provided, e.g., in consultancy via the use of recommender systems. We explore the special characteristics of such knowledge-based B2B services and propose a process that all...

Practitioners in business information systems are frequently faced with tasks that involve interpretation and representation of organizational information as models, e.g. business processes, the involved participants, and data. Usually, this information comes from varied sources like stakeholders and documents, often resulting in subjective, biased...

Besides the typical applications of recommender systems in B2C scenarios such as movie or shopping platforms, there is a rising interest in transforming the human-driven advice provided e.g. in consultancy via the use of recommender systems. We explore the special characteristics of such knowledge-based B2B services and propose a process that allow...

This chapter discusses the design of a dialog-based intelligent tutoring system for the domain of Business Information Systems education. The system is designed to help students work on group projects, maintain their motivation, and provide subtle hints for self-directed discovery. We analyze the domain of Business Information Systems—which we find...

“Boxology” is the graphical representation of patterns that are commonly observed in hybrid learning and reasoning systems. Since some hybrid systems also involve humans-in-the-loop, a need to identify patterns including humans is foreseen. With the help of use cases that involve humans-in-the-loop, this chapter provides a discussion on the typical...

Exploring a knowledge base is often an iterative process: initially vague information needs are refined by interaction. We propose a novel approach for such interaction that supports sequential question answering (SQA) on knowledge graphs. As opposed to previous work, we focus on exploratory settings, which we support with a visual representation o...

A majority of managers does not know what it means and how to leverage the development of new technologies and disruptive innovations for their business. Furthermore, doing business is getting increasingly complex due to globalization and specialization. Thus, it looks like everyone is hyperactively looking for an external solution to their manager...

The support of workplace learning is becoming increasingly important as change in every form determines today’s working world in the industry and public administrations alike. Adapting quickly to any kind of change is just one aspect. Another is dealing with the information relevant to this change. A recommender system for workplace learning was de...

Purpose Business processes of public administrations (PAs) are often described in the form of written procedures or operational manuals. These busi- ness process descriptions are expected to be properly understood and applied by civil servants, who have to provide legally-compliant service provisions to the citizens. However, process descriptions...

The support of workplace learning is increasingly relevant as the change in every form determines today’s working world in the industry and public administrations alike. Adapting quickly to a new job, a new task or a new team is a significant challenge that must be dealt with ever faster. Workplace learning differs significantly from school learnin...

Die Digitale Transformation hat Hochkonjunktur: Seit etwa 2014/2015 gehört dieses Schlagwort zum Handwerk aller Mitarbeitenden in Beratungsfirmen und auf Geschäftsleitungs-, Abteilungs- und Projektleitungsebenen. Die Treiber der Digitalen Transformation sind unzählige neue Datenquellen, neue Technologien sowie Anforderungen vom Markt und von Gesch...

This paper discusses how usage patterns and preferences of inhabitants can be learned efficiently to allow smart homes to autonomously achieve energy savings. We propose a frequent sequential pattern mining algorithm suitable for real-life smart home event data. The performance of the proposed algorithm is compared to existing algorithms regarding...

Business intelligence (BI) projects have the goal to implement suitable tools for decision support and to integrate them with existing data sources in a company. They have therefore been on CIOs agendas for several years and there are still a lot of BI projects to come. Despite this fact, however, still the majority of BI projects fail to deliver t...

This paper presents a case study of a recommender system that can be used to save energy in smart homes without lowering the comfort of the inhabitants. We present an algorithm that uses consumer behavior data only and uses machine learning to suggest actions for inhabitants to reduce the energy consumption of their homes. The system mines for freq...

Customer or market segmentation is an important instrument for the optimisation of marketing strategies and product portfolios. Clustering is a popular data mining technique used to support such segmentation – it groups customers into segments that share certain demographic or behavioural characteristics. In this research, we explore several automa...

Managing information based on hierarchical structures is prevailing, be it by storing documents physically in a file structure like MS explorer or virtually in topic trees as in many web applications. The problem is that the structure evolves over time, created individually and hence reflecting individual opinions of how information objects should...

Information repositories, implemented as Enterprise Portals (EP) on the intranet, are increasingly popular in companies of all sizes. Enterprise Portals allow for structuring information in a way that resembles the organization of paper copies, i.e. simulating folders and registries and furthermore, provide simple routines for publishing and collab...

This paper presents the results of three interlinked case studies in companies who have recently introduced Wiki software. The case studies were all conducted with the same methodology, starting with an interview with the responsible person, design of a survey based on the interview findings and then application and interpretation of the survey. Th...

In modern organisations there is the necessity to collaborate with people and establish interpersonal relationships. Contacting the right person is crucial for the success of the performed daily tasks. Personal email corpora contain rich information about all the people the user knows and their activities. Thus, an analysis of a person's emails all...

The work presented in this paper explores the potential of leveraging the traces of informal work and collaboration in order to improve business processes over time. As process executions often differ from the original design due to individual preferences, skills or competencies and exceptions, we propose methods to analyse personal preferences of...

This paper presents novel algorithms to support the continuous development of ontologies; i.e. the development of ontologies during their use in social semantic bookmarking, semantic wiki or other social semantic applications. Our goal is to assist users in placing a newly added concept in a concept hierarchy. The proposed algorithm is evaluated us...

We introduce a new approach supporting knowledge workers in sharing process-related knowledge. It is based on the insight that – while offering valuable context information – traditional business process modelling approaches are too rigid and inflexible to capture the actual way processes are executed. Therefore, business process models are made ag...

Ontologies are an important part of the Semantic Web as well as of many intelligent systems. However, the traditional expert-driven development of ontologies is time-consuming and often results in incomplete and inappropriate ontologies. In addition, since ontology evolution is not controlled by end users, it may take too long for a conceptual chan...

This paper experimentally studies approaches to the problem of describing heterogeneous information sources in distributed environments. In particular, we consider a scenario where a large number of end users can share and retrieve text documents over a peer-to-peer network. Descriptions (or profiles) of peers are useful in a number of applications...

We address the problem of evaluating peer-to-peer information retrieval (P2PIR) systems with semantic overlay structure. The P2PIR community lacks a commonly accepted testbed, such as TREC is for the classic IR community. The problem with using classic test collections in a P2P scenario is that they provide no realistic distribu- tion of documents...

Pattern based task management has been proposed as a promising approach to work experience reuse in knowledge intensive work environments. This paper inspects the need of organisational work experience sharing and reuse in the context of a real-life scenario based on use case studies. We developed a task pattern management system that supports proc...

We introduce the concept of organizational knowledge maturing based on the idea of developing knowledge assets. We explain the dimensions that have to be considered and introduce the Knowledge Maturing Dimension Framework to measure the maturity level. Finally we describe service classes as the building blocks of a future organizational learning an...

This paper experimentally studies approaches to the prob- lem of ranking information resources w.r.t. user queries in peer-to-peer information retrieval. In distributed environ- ments, for each given user query and a set of information re- sources that are available, we need to select the right subset of these resources to forward the query to. Her...

This paper examines the estimation of global term weights (such as IDF) in infor- mation retrieval scenarios where a global view on the collection is not available. In particular, the two options of either sampling documents or of using a reference corpus independent of the retrieval collection are compared using standard IR test collections. In ad...

This paper is concerned with the evaluation of distributed and peer-to-peer information retrieval systems. A new measure is introduced that compares results of a distributed retrieval system to those of a centralised system, fully exploiting the ranking of the latter as an indicator of gradual relevance. Problems with existing evaluation approaches...

This paper introduces a system for automatic query expansion. It is aimed at helping users to search for text documents in the World Wide Web through the usage of local text corpora residing on the user's computer. These text documents are used to select appropriate terms to expand search queries. With this technology the search context is not just...

This paper studies the impact of the tail of the query distribution on caches of Web search engines, and proposes a technique for achieving higher hit ratios compared to traditional heuristics such as LRU. The main problem we solve is the one of identifying infrequent queries, which cause a reduction on hit ratio because caching them often does not...

The thesis presented in this paper tackles selected issues in unstructured peer-to-peer information retrieval (P2PIR) systems, using world knowledge for solving P2PIR problems. A first part uses so-called reference corpora for estimating global term weights such as IDF instead of sampling them from the distributed collection. A second part of the w...

This paper introduces multi-level associa- tion graphs (MLAGs), a new graph-based framework for information retrieval (IR). The goal of that framework is twofold: First, it is meant to be a meta model of IR, i.e. it subsumes various IR models under one common representation. Sec- ond, it allows to model different forms of search, such as feedback,...

tftd+µp(t|C) |d|+µ , where p(t|C) is term t's relative frequency in the collection, tftd its fre- quency in document d and µ a smoothing parameter. Analytically, since each factor in the above product is smaller than one, it can be thought of as a penalty. This penalty has a strong impact if a term is not contained in a document (tftd = 0) and even...

We present Ord i Dag, a new service that displays today’s most important keywords. These are extracted fully automatically from Norwegian online newspapers. Describing the complete process, we provide an entirely disclosed method for media monitoring and news summarization. For keyword extraction, a reference corpus serves as background about avera...

This paper reports on information retrieval experiments aimed at application in ubiquitous or P2P environments. The main question to be investigated is whether global term statistics such as IDF - which normally require a global view on the document collection - can be re- placed with estimates obtained from a representative (i.e. well-balanced) re...

This paper addresses the issue of peer profiles, i.e. compact representations of a peer's locally offered content, and their use in P2P information retrieval and routing. Experiments with different profile building and query expansion methods show that compression of profiles is possible without losing too much retrieval performance and that query...

Since there is a continuously growing amount of lexical acquisition algorithms for all kinds of lexical knowledge, be it morphologic, syntactic, semantic, domain specific or other information, it is necessary to be able to compare their quality. Furthermore at the same time it is necessary to provide an evaluation method that is easy to grasp and a...

Topic Maps are sophisticated indexes for dynamic, heterogeneous, structured, and unstructured information sources. In order to move Topic Maps towards the mainstream, the automatic generation of Topic Maps and its integration in the users working environment and processes must be improved. Our described approach for Topic Map generation is based on...

The central theoretical criteria of Topic Maps “One Topic for one Subject” leads to serious problems if two distributed Topic Maps are merged: according to existing standards, two Topics will only be merged if the description of their Subject (i.e. their so-called Subject Identifier or Subject Locator) is exactly identical. On the other hand – from...

This article presents a new algorithm for content-oriented search in P2P networks that avoids flooding and thus ensures scalability. It is based on the concept of small worlds: peers are enabled to actively influence network structure by choosing their neighbours. Different strategies for neighbour selection are possible, the most important being t...

This paper introduces extended Multi-Level Association Graphs (short eMLAGs), a meta-model for adaptive information retrieval. The goals of this framework are two-fold: First, it subsumes existing techniques for adaptive information retrieval, easing their comparison and merging. Second, it aims at being a tool for stimulating the discovery of new...

Lexical taxonomies have tree-like structures and can thus be extended to become deci- sion trees that serve for their own extension. In this paper, a semi-automatic procedure for extending lexical taxonomies is proposed that makes use of term extraction methods for identifying new concepts and that uses co- occurrence data from large corpora to gen...

This paper introduces a new linguisti- cally motivated feature selection tech- nique for text categorization based on morphological analysis. It will be shown that compound parts that are constituents of many (different) noun compounds throughout a text are good and general indicators of this text's content; they are more general in meaning than th...

This work presents a new approach to handling knowledge-intensive business processes in an adaptive, flexible and accurate way. We propose to support processes by executing a process skeleton, consisting of the most important recurring activities of the process, through a workflow engine. This skeleton should be kept simple. The corresponding workf...

Although most enterprises nowadays increasingly employ digital informa-tion management in all areas, there are still many organisations – e.g. in the Public Sector – where much of formal and informal information is documented on paper only. This work lays out the concept of a set of digital metaphors for entities in the "paper world" and argues tha...