Hypertext systems support users in navigating structured data sets and to find relevant information. Various interaction and visualization concepts aim to give users better insight into the data set, by suggesting queries and visualizing elements of interest in a meaningful way. Ranked lists are very common to show some sort of priority, while spatial layouts often help users to trace relations in the data. Only little research has been done in user studies that systematically show and reason about the differences of such spatial layouts and ranked lists. In this paper we report on a systematic comparison of a spatial visualization versus a ranked list layout. For this purpose, we did an between-subject study with 43 participants. One group performed a task with a system providing semantic visualization in 2D, the other group performed the same task with a ranked list. Both interfaces are very similar and only differ in how suggestions are visualized. The results show that users of the spatial layout finished their task in shorter time and have a tendency towards higher satisfaction. At the same time, they had more interactions with the system. Furthermore we discuss some in-depth data of the test sessions, which show that the visualization influences the users’ behavior.

In this paper, we report on a software demonstrator that utilizes a spatial hypertext UI to support knowledge management in the context of maintenance in industry. To demonstrate the flexibility of that approach, we re-use the software to visualize bibliographic data of the Hypertext conference series.

Associating information by means of linking it is a universal concept of human thinking, and by constructivist means, a possible way of learning through exploring and constructing individual information spaces related to a topic or cross topics. An application, facilitating and externalizing this activity by enabling users to create individual hyperlinks inside the environment of the Web, is a promising way to satisfy this exploratory use of information. The focus on an augmentative approach by lining hypertext's linking paradigm, in conjunction with the Web's vast amount of information, opens up for a broad spectrum of potential use scenarios. The possibilities reflect potential complexities concerning usability and limitations of usage. Therefore, preliminary and iterative evaluations are indispensable for meeting these challenges. We discuss a preliminary evaluation of usability and user behavior of said application by a conducted study based on cross-sectional quasi experimental design, using a controlled test scenario and collected client side data that serves as basis for interpretation on user behavior. Results indicate a strong habituation to document-centric processing and storing of information, and the tendency for transferring this behavior onto the more versatile linking mechanism introduced by the application. We argue for applying additional supportive features, specific for facilitating the reduction of complexity on user-side, and a longer testing period, in order to gain better insight into the possible overcome of habitual patterns concerning the tested use scenario.

This blue sky paper envisions a novel system which promotes emotional closeness through storytelling. Family members, who may be separated, collaboratively build a spatial hypertext of images and text fragments to express and structure their thoughts and memories. The system observes their reactions as well as their media while they work. Live recommendations prompt users in their thinking and storytelling. Family stories are thus collaboratively adapted to more tightly connect the thoughts and emotions of their loved ones.

This paper presents a way for the hypertext community to gain strength and contribute to other fields of research by joining forces. It discusses the challenges that need to be addressed with respect to geographically scattered students and scholars, interdisciplinary courses, and students with various foreknowledge. We propose the INTR/HT project, a platform that aims for bringing hypertext scholars and students together worldwide. The interdisciplinary approach fosters creativity in the context of hypertext and is valuable for educating and supporting the next generation of hypertext scholars and researchers.

Modern browsers, as we know them from the Web, are used to query and present a variety of different resources. This usually happens by traversing links (i.e., URIs) in hypertext documents. The creation of new links however, is impossible to ordinary users, because they usually are recipients, but not owners of the received resource. In this paper, we demonstrate a browser plugin called "Weblinks", which offers its users an additional and rich linking layer over the existing Web. This enhances the notion of links as strings (i.e., URIs) in today's Web context to links as rich objects (n-ary, unidirectional, or bidirectional), which can be created, traversed or shared by anyone using the Weblinks browser plugin.

Information retrieval systems support users in finding relevant information in data sets. List layouts are wide-spread, but spatial layouts are catching up. User studies that systematically show their benefits for users are missing. We report on a comparative between-subject study with 43 participants comparing a spatial layout with a list layout. One group performed a task with a system providing semantic visualization, and the other group performed the same task with a system without semantic visualization. The results show that the users of the spatial layout had significantly more interaction with the system in shorter time, with a slightly higher outcome and higher satisfaction.

Human Factors in Hypertext 2021 (HUMAN'21) is the 4th workshop in this series. It is sponsored by ACM SIGWEB and is associated to the ACM Conference on Hypertext and Social Media 2021, which took place between August 30th and September 2nd as a virtual event. HUMAN'21 took place on August 30th-the conference's workshop day. This year's workshop is held in a difficult time: the global Corona pandemic makes attending meetings or traveling risky for our health. It almost seems as a contradiction to the 2019 ACM Hypertext motto "tear down the wall". However, today's digital media enables us to communicate over distance or even attend larger meetings online. This also opens the question about the role of hypertext as a medium for communication-a perfect topic match for the HUMAN workshop series, which has a user-centric focus on hypertext. The user-centric view not only includes user interfaces and interaction, but also discussions about hypertext application domains. Furthermore, the workshop raises the question of how original hypertext ideas (e.g., Doug Engelbart's "augmenting human intellect" or Frank Halasz' "hypertext as a medium for thinking and communication") can improve today's hypertext systems. As such, the HUMAN workshop also appreciates previous work on hypertext systems. In order to support this, we invite researchers to give demos of vintage hypertext systems. Last year we started with Norman Meyrowitz presenting Intermedia; this year Mark Anderson has been invited to give a demo of Microcosm.

Historically, there has been a tendency to consider hypertext as a type of system, perhaps characterised by provision of links or other structure to users. In this article, we consider hypertext as a method of inquiry, a way of viewing arbitrary systems. In this view, what are traditionally called “navigational hypertext systems” might be considered as information retrieval systems. This opens the hypertext field to various other types of systems that traditionally would not be considered as part of the field. The change of view enables a deeper fusion of human and machine. In particular, today's AI-based, intelligent systems open the demand of synthesising automation (on the machine's side) and augmentation (on the user's side). This article is not about researching AI systems; it is about extending the view of hypertext systems to synthesise augmentation and automation. We specifically apply this view to intelligent systems, asking the question about how hypertext can act as a common medium between human and machine, particularly for knowledge intensive tasks. We propose spatial hypertext as a medium that enables users to create cognitive maps. Along these lines, we provide examples from multiple projects and examine how these applications can be productive.

Without any doubt, creating links and navigational trails is fundamental to hypertext. The Web is the widest spread representative among all systems in the history of hypertext, although its underlying core concept is kept simple. This is why the Web's widely used link functionality is naive, supporting only embedded, unary and unidirectional links. A strength of the Web is its extensibility, giving us the opportunity to augment the current functionality of links. We showcase a browser plugin, which enables users to create and share complex links over the existing Web. Furthermore, we discuss the CB-OHS Mother, its link model and how this relates to existing work. The implementation adopts latest standardization efforts and is an update to older attempts of enabling external link services for the Web.

This blue sky paper presents the Thoughts Reflection Machine (TRM) which combines hypertext technologies and intelligent components. Using hypertext, the TRM provides means to its users to express or communicate their thoughts and ideas. Furthermore, the machine suggests relevant information that trigger users' creative thinking. The TRM is an approach towards a tight cooperation between human and machine supporting both in their specific tasks in which they are most excellent in: creative problem solving respective computation of huge data sets.

User behavior and the resulting behavioral data forms the basis of personalized feeds, recommendations and advertisements in social networks such as Facebook. These platforms are now required to provide users with their personal data. However, these dumps with chronological data in different files do not provide users insight in overarching themes and connections in their online behavior. In this paper, we discuss the development and preliminary evaluation of an exploratory interface for visual data exploration. First insights include that the less obvious, more associative and obscure connections are more interesting and relevant to the user than very close semantic or temporal connections.

Social networks such as Facebook are required to provide users with their personal data. However, these dumps do not provide users insight in overarching themes in their online behavior. In this poster, we discuss the development of Mother, a spatial hypertext system for visual data exploration. First insights include that the less obvious connections are more interesting and relevant to the user than very close semantic or temporal connections.

Social networks use several user interaction techniques for enabling and soliciting user responses, such as posts, likes and comments. Some of these triggers may lead to posts or comments that a user may regret at a later stage. In this article, we investigate how users may be supported in reflecting upon their past activities, making use of an exploratory spatial hypertext tool. We discuss how we transform raw Facebook data dumps into a graph-based structure and reflect upon design decisions. First results provide insights in users motivations for using such a tool and confirm that the approach helps them in discovering past activities that they perceive as outdated or even embarrassing.

It is our great pleasure to welcome you to the 30th Anniversary ACM Conference on Hypertext and Social Media at Hof University, Germany, on September 17-20, 2019. The ACM Hypertext conference is a premium venue for high quality peer-reviewed research on hypertext theory, systems and applications. It is concerned with all aspects of modern hypertext research including social media, semantic web, dynamic and computed hypertext and hypermedia as well as narrative systems and applications. The theme of Hypertext 2019 is "HYPERTEXT - TEAR DOWN THE WALL". This motto of the 30th ACM Hypertext conference goes hand in hand with the 30th anniversary of the fall of the Berlin Wall. Inspired by the historical events in Germany, Hypertext 2019 aims at reunifying different hypertext research directions and communities. Therefore, apart from the regular research tracks, Hypertext 2019 will feature a research track on 30 Years of Hypertext as well as an exhibition/creative track. 2019 will also be the 30th anniversary of the WWW. It is a perfect time to join in, reflect our common roots, and discuss how we can jointly address our current and future challenges. The conference will take place at the Institute of Information Systems (iisys) at Hof University, Germany. Hof lies midway between Frankfurt and Prague, Munich and Berlin and is very close to the former German-German border, in particular to the village of Modlareuth, called "little Berlin", which used to be divided by a wall. After exactly 20 years, Hypertext 2019 will take place in Germany again for the 2nd time. Hypertext 2019 is co-locating with the ACM Document Engineering Conference (DocEng'19) organized in Berlin, Germany, between September 23-16.

Welcome to the Human Factors in Hypertext 2019 workshop (HUMAN'19) in Hof, Germany, the second workshop of a young series of workshops for the ACM Conference on Hypertext and Social Media. It has a strong focus on hypertext users and thus complements the machine analytics research that we experienced in previous conferences. The user-centric view on hypertext not only includes user interfaces and interaction, but also discussions about hypertext application domains. Furthermore, the workshop raises the question of how original hypertext ideas (e.g., Doug Engelbart's "augmenting human intellect" or Frank Halasz' "hypertext as a medium for thinking and communication") can improve today's hypertext systems. Historically, hypertext research strongly connects to human factors. Hypertext pioneers, such as Doug Engelbart or Ted Nelson, focused on the usage of and interaction with hypertext. This workshop combines original hypertext research ideas with recent hypertext research trends. In addition, it consolidates different hypertext research areas from the viewpoint of human factors. Thus, HUMAN'19 fosters cross-cutting discussions and the development of new ideas.