Designing digital signage for better wayfinding performance: New

Designing Digital Signage for Better Wayfinding Performance New Visitors’ Navigating Campus of University Sungyeon Kim1, Eunil Park1, Sean Hong1,2, Yoonhee Cho1, Angel P. del Pobil1,3 1

Department of Interaction Science Sungkyunkwan University Seoul, South Korea [email protected]

2

Device R&D Center KT Corporation Seoul, South Korea [email protected]

Abstract—With ever increasing consumer interest growing in digital signage, wayfinding digital signage was gaining momentum. However, many places are still having problems of confusing signage. This study was to explore how to design user centered digital signage for better wayfinding performance. This study focused on evaluating campus information digital signage as a wayfinding tool, which can be valuable for campus visitors. This paper examined two evaluations, formative evaluation and summative evaluation, in the context of how users were judging a worth of a system with regard to digital signage design prior to construction, and testing the validity and determining the impact of digital signage design. Results indicated that digital signage was more efficient than paper signage or traditional signage. The integration of these methods would help to identify effective content and design features of wayfinding digital signage for future study. Keywords-wayfinding; signage; navigation; visiting

I.

INTRODUCTION

Digital signage, as a form of electronic display that shows information, is rapidly becoming a mainstay of a universal communication platform [1-7]. Digital signage is viewed primarily as marketing tools, but their potential goes well beyond the promotion of products and services [3, 6]. Not only digital signage attracts attention and is easy to update and changes contents easier and better than static printed signage, digital signage has already proven its ability to magnify a company’s visibility, to deliver information more efficiently and to solidify relationships between customers and vendors. The use of digital signage is spreading throughout numerous markets including retail, higher education, banks, travel hubs and corporate headquarters to deliver informative and entertaining content to captive audiences and passersby [5, 7]. The digital information extends from the purely practical to the educational and entertaining. With rapid technology development, by contrast, it is becoming more sophisticated with too many menus and even inconsistent, diversified contents as well [8, 9]. However, many studies focused on the problem of confusing signage [1, 2, 7]. Travelers or visitors commonly experience frustration of disorientation and get lost because

3

Robotic Intelligence Laboratory Universitat Jaume-I Castelló, Spain [email protected]

they tend to give less information or too much information at once [10-12]. Legibility is the key factor to read signage. The interfaces need to be organized in an understandable hierarchy in order to not make users distract and confuse; use digital signage to keep users informed, make more enjoyable, comfortable, and reduce times. It is important to make the media easy to use in shared information environments. Digital signage can be a great way-finding tool campus information network can be a primary welcome point for campus visitors. A quick and easy progression to feeling comfortable with the system is crucial for users [1, 5, 7]. There are several elements that go into producing digital signage, but the most important element is making it relevant information for the users. The purpose of this study is as to how we can use digital signage content to be useful and still have identity of where it place to deliver information, bring out fun part of experience, and reduce time of use. This study examines how to effectively and efficiently incorporate way-finding strategies in the information seeking process, with analyses provided of university digital signage contents. Many studies have been argued the impact of way finding in signage with various aspects of user and stimulus side. Passini [13] explained three interrelated processes of wayfinding in terms of decision making and the decision execution. Sequential egocentric map is structured as a function of a person's movement through the setting [14] and districts such as paths, edges, districts, nodes, landmarks help egocentric point of view [15]. Also, many theories of spatial cognition have been developed to account for wayfinding and most of computational models focused on knowledge representation as well (e.g. cognitive maps). Tergan [16] analyzed the potential of digital concept maps for supporting processes of individual knowledge management, and process spatial information at the geographic scale [16, 17], and the cognitive mapping process and wayfinding [18, 19], etc. However, many researchers do not consider the process of how people structure wayfinding tasks [4-7, 16, 17, 19]. This study focuses on what makes visitors troubled them in the university with map and directory signage; how visitors interact with existing static-printed signage and new digital signage; this study investigates what are the influences to users

This study was supported by a grant from the World-Class University program (R31-2008-000-10062-0) of the Korean Ministry of Education, Science and Technology via the National Research Foundation.

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as they observe and find their destination on signage and get to their destination. Arthur and Passini [20] referred to wayfinding as a ”continuous problem solving process.”. The success of each wayfinding step depends on the success of the one before it, and these steps must be solved in a particular order. In addition, this study presents a series of usability evaluation method to develop user centered digital signage through the process of how users perceive wayfinding tasks with regard to spatial representation and knowledge of wayfinding as well. II.

another, and survey knowledge as abstract and spatial knowledge that will allow drawing an accurate map. The signage system which is primarily designed to help people navigate can be evaluated whether it is well designed and developed and can be guided to a better design according to this LRS model [36] (see Table 1). TABLE I. Category

Landmark

LITERATURE REVIEW

A. Signage System and Wayfinding Calori and Chermayeff [21] wrote on his book that signage and wayfinding design are an essential reference for designers who must communicate meaningful information in the built environment. The system for people who travel to find a way to a desired place is one of interesting research topics for architectural engineering and design [22], industrial and interaction design, and environment and urban engineering and design [23]. Their targeted objects for research are also various according to user side - e.g., drivers [24], tourists [23], students [12], and disabled people [25], - and stimulus side – e.g., map, directory [22], and evacuation sign for emergency [26], etc. Digital signage only for wayfinding is rare due to price of system such as displays, servers, and network infra. Many of previous researches have been consequently focused on consumption of digital contents such as those for commercial, advertising, artistic, or entertainment purposes [27-29]. and on signage systems which has initiative over viewers in the perspective of interaction, e.g. signage learns the audiences’ attention [5] and sensing viewers and interacting with them [30]. On the contrary, people generally have intuitive over signage systems for disorientation and getting lost are commonly very frustrating experiences for them who are trying to reach a specific destination. Factors for effective interaction design of digital contents, such as reduction of mental workload [31-33] and simplicity [34]. Designing signage systems which will prevent people getting lost and help them to perform better wayfinding, designers should keep in mind what kind of knowledge they have during their wayfinding and how they process spatial information. B. Knowledge of Wayfinding Siegel and White [35] proposed Landmark-RouteConfiguration model to explain spatial representation and knowledge of wayfinding of which function is primarily to prevent getting lost and to facilitate location and movement within the environment. Knowledge of landmark is descriptive information of noticeable places within an environment. Knowledge of route is knowledge of mentally defined routes between locations. Configuration knowledge is spatial knowledge in the form of a mental map of an environment [35]. This model is very widely adopted in the research field of wayfinding and spatial representation; Wickens [36] presented this model as LRS (Landmark, Route and Survey) Model: Landmark knowledge as visual representation, Route knowledge as verbal knowledge how to get from one place to

Route

Survey

LRS MODEL FOR KNOWLEDGE OF WAYFINDING. From Siegel and White [35] Descriptive information of noticeable places within an environment. Knowledge of mentally defined routes between locations. Spatial knowledge in the form of a mental map of an environment.

From Wickens and Hollands [36], Torndyke and Roth [37]. Visual representation. Verbal knowledge how to get from one place to another. Abstract and spatial knowledge that will allow to draw an accurate map.

C. Process of Wayfinding Passini [13] explored on process of wayfinding. Wayfinding is composed of three interrelated processes; 1) decision making and the development of decision plans: 2) decision execution, transforming decision plans into behavior at the right time and place along a route: and 3) information processing, comprising environmental perception and cognition which provide the person with the information necessary for the two decision related processes [13]. As visitors encounter a signage which will guide to their destination, they follow this process of wayfinding. In order to enhance the performance of navigators’ wayfinding, elements or features of a signage system must be designed enhance each of the steps of wayfinding process. Following the relation of the previous literature that provided conceptualization of content on digital signage, its relation to effective way-finding, one research question is formulated below for this current study. x

Research Question: Controlling for new visitors, what is relationship between content & design features of digital signage and the level of perceived information quality (landmark, route, and survey) and satisfaction?

The present study is to evaluate the effects of digital signage for better wayfinding performance. First of all, satisfaction has all been found to be statistically significant in their relationships with performance. This reasoning leads us to propose the first hypothesis: x

H1: Users with improved digital signage will perceive it satisfied compared to paper or traditional signage.

In addition, information quality (IQ) is vital to organizational success [38]. To evaluate the contents and design features of digital signage, this study applied the LRS model as information quality. The signage system which is primarily designed to help people navigate can be evaluated whether it is well designed and developed and can be guided to a better design according to this LRS model. Specifically, the following hypotheses are proposed:

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x

H2: Users will perceive that the design features of digital application of landmark-knowledge are more useful than those with paper or traditional signage.

x

H3: Users will perceive that the design features of digital application of route-knowledge are more useful than those with paper or traditional signage.

x

H4: Users will perceive that the design features of digital application of survey-knowledge are more useful than those with paper or traditional signage. III.

METHOD

A. Study Design In order to test the research questions and hypotheses mentioned above, we designed 1) formative evaluation to provide information useful in improving content and design features of digital signage and 2) summative evaluation to judge/identify the worth of our project with the level of perceived information quality and satisfaction at the end of the program activities. 1) Formative Evaluation: Formative evaluation, as a process of ongoing feedback on performance, was conducted to guide decision-making on design revisions: Field interview, Cognitive walkthrough, and Heuristic evaluation. For field interview, contextual inquiry & think Aloud by interviewing, observing, and recording data were conducted. Participants were 10 graduate students (5 females, 5 males, average age of 26) and 10 experts who were professors and researchers of cognitive science and geography from a private large university in Seoul for usability test. A stimulus was the university existing print signage, which is campus map and directions on the main gate of the school to support and design our digital signage (See Figure.1). Procedure was as follows: 1) Instruct each of them to navigate different destination, in which facilitator designate 2) During navigating the destination on map, we observed/interviewed, and used with recording to get users’ internal thoughts. 3) Instruct them to go to the destination.

of our defined tasks; 1) identify the destination on map 2) identify the path to the destination on map 3) navigate to the destination. At each step of a task, usability specialists answered the four cognitive questions; 1) Will the user try to achieve the right effect? 2) Will the user notice the interface for currently available action? 3) Will the user recognize that it produces the effect trying to be achieved? 4) Will the user see/understand the feedback he/she get toward the goal? After evaluating, they reported each usability issue discovered during walkthrough. In addition, heuristic evaluation was used to justify every problem with Nielsen’s traditional ten heuristics. Evaluators debriefed a list of usability problems. As a result of formative evaluation, 15 potential problems and 6 design ideas were identified (see Table 2); of 15 potential problems generated during formative evaluation, 11 problems were discovered in field interview, 1 new problem was added during the cognitive walkthrough, and 3 problems were newly discovered in heuristic evaluation. Six design ideas derived from 15 potential problems were specific solutions for our design guide line. Through the evaluation, task analysis could be applied to studying how users use this existing signage to identify landmark, route, and survey knowledge in the process of understanding the difficulties they face. TABLE II. PROBLEMS AND DESIGN IDEAS THROUGH FORMATIVE EVALUATION Problem 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.

Figure 1. Existing signage at the main gate of the university.

For cognitive walkthrough and Heuristic evaluation, we approached to evaluate the interface without users to catch problems that testing with a few users would miss. Two usability specialists participated in analyzing this signage as evaluators to each of cognitive walkthrough and Heuristic evaluation. We conducted a cognitive walkthrough evaluation of the university existing print signage, stepping through three

Labeling problem of building No information of facilities in the building No name of building on map Can’t notice a sense of distance on map No information on present floor on building directory Readability and legibility of index of directory and its number Confused ‘corrent location’ sign No clear street name and colors Difference between map and real objects No indicated main road No direction signs Too small map Too small English signs Language order problem No needs of other campus maps

Design ideas

1.

2. 3.

4. 5. 6.

Consistent name of destination building and streets Indication of directional sign Consistent between real distance, objects and topology Placing ‘current location’ on the right position. Removing unnecessary information. Legibility of information on map

2) Design Guidelines: In order to establish a design guideline for digital signage the problems derived from three different analyses are categorized according to LRS model. (See Table 2) Problems of labeling (no label or wrong label of buildings and streets) and cue for landmarks (no specific cue) are categorized as characteristic of lack of landmark knowledge. Problems of directional sign (no directional sign) and exact guides for routes (neither visual nor verbal guides) are categorized as lack of route knowledge. Problems of difference between real and signage (different distance and

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image), illegibility (using unfamiliar words), and confusion of egocentric and exocentric view (confusing “you are here” sign) are categorized as lack of survey knowledge. Design guidelines were extracted from this metrics of problems. Regarding Landmark knowledge, guidelines of displaying visual cue on land mark and exact, consistent, and detailed information about destination was established. Regarding Route knowledge, guidelines of showing visual and verbal guide of direction and route information combined with landmark design was developed. Guidelines of enhancing legibility (language & IA) and offering well-organized and appropriate egocentric and exocentric information was extracted regarding Survey knowledge. Responding each of guidelines, list of design features for user centered digital signage for better performance of wayfinding were completed (See Table 3). TABLE III.

was used ‘apps’ as a tool for creating interactive interface and contents, including LRS (land marks, routes, & survey) knowledge based on design guidelines derived from formative evaluation (See Figure.2). In case of paper signage, we gave participants small map and snap shot which were A4 size.

TABLE TYPE STYLES Problem

knowledge

Field Interview / Cognitive Walkthrough / Heuristic Evaluation

Lack of knowledge

Landmarks

x Different (or no) name of destination buildings and streets

No specific cue of landmarks

Route

x No directional sign

No guidance (verbal/visual) for exact route

Survey

x Difference between real distance (or objects) and topology x Confusing ‘corrent location’ sign x Unnecessary information x Illegibility of information on map

Confusing egocentric & exocentric map

Figure 2. Improved digital signage system.

B. Summative Evaluation 1) Design: In order to test the research questions and hypotheses mentioned above, we designed an experiment to test the effect of improved digital signage. 32 people, who never visit the university, were assigned to participate in the experiment. Our new improved digital signage for the map of university was used to evaluate the level of perceived information quality and satisfaction. A between-subjects experiment was conducted, with two conditions (digital signage vs. paper and traditional signage). 2) Participants: Participants were 32 people who were given a chance to voluntarily participate for the experiment through personal contacts. The sample was 50 % men (n=16) and 50% women (n=16). The age range of the survey population was between the ages of 21 and 37. The mean age was 27.8 years (SD = 3.2). The experiment for each subject lasted about 20-30 minutes. After the experiment, they were debriefed and paid five dollars for their participation. 3) Apparatus and Stimuli Material: The present study intentionally chose laptop computers to allow participants to navigate outside, the main gate of the school. Two highperformance tablet with identical hardware specifications were used; iPad 2 was selected. The improved digital signage system was initially created for stimulus material: This system

4) Procedure: Of total 32 participants, 2 participants of 16 groups came to the main gate of the school for every half hour. 8 groups were assigned as paper signage condition. 8 gropus were assigned as digital signage condition. Participants were told that they would participate in a research project for around 20-30 minutes. Prior to the implementation of the experiment, participants were administered an online questionnaire measuring participants’ level of spatial and navigational abilities, preferences, and experiences. A 7-point Likert scale (1=”strongly disagree”, 7=”strongly agree”) questionnaire consists of 8 items adapted from previous selfreport scales, the Santa Barbara Sense-of-Direction Scale (Hegarty, Richardson, Montello, Lovelace, & Subbiah, 2002). Participants were provided with a brief instruction on navigation of digital signage and the destination and instructed to go to their destination when they found their destination. After that, an online questionnaire measuring participants’ level of perceived information quality and satisfaction with paper signage and new digital signage were adopted. Participants were then debriefed, paid five dollars, and thanked for their participation. 5) Measurements: This study operationalized evaluating the user-centered digital signage for better wayfinding performance on our improved the university signage measuring variables including two dependent variables; the

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level of perceived information quality in dimensions of LRS knowledge, and the level of satisfaction.

knowledge (α=.79) were identified. The items were asked in a 7-point Likert scale that ranged from “strongly disagree (1)” to “strongly agree (7)”. b) Satisfaction: Schuler [41] finds support for increases in satisfaction when information is systematically available. To re-examine the level of perceived information quality, user satisfaction rate was measured with a scale in a post-test survey questionnaire by asking participants to responds to 6 items (α=.90). The questionnaire items were created based on previous studies using a 7-point Likert scale, ranging from “strongly disagree (1)” to “strongly agree (7).” [42]. IV.

In order to evaluate the overall effect of the user centered digital signage for better wayfinding performance usability data from formative evaluation and summative evaluation were collected. Evaluation of the hypotheses according to the result of post-survey questionnaire was preceded. An analysis of variance (ANOVA) was conducted to analyze the effects of digital signage, followed by post-hoc analyses using Student’s t test. The results from the ANOVA and a subsequent post-hoc analysis indicated that participants with improved digital signage (M = 6.00, SD = 0.72) reported a significantly higher degree of satisfaction than those with paper signage (M = 4.24, SD = 0.76), F(1, 30) = 44.76, MSe = 24.85, p < .001. Therefore, H1 was supported. Participants also reported that digital signage (M = 5.92, SD = 0.98) was more useful than paper signage (M = 4.55, SD = 0.80) to perceive design features of land-knowledge, F(1, 30) = 18.58, MSe = 14.99, p < .001. Additionally, participants reported that digital signage (M = 5.55, SD = 1.19) was more useful than paper signage (M = 4.65, SD = 0.78) to perceive design features of route-knowledge (F(1, 30) = 5.70, MSe = 5.78, p < .05) , while paper signage (M = 4.97, SD = 1.23) elicited a greater level of usefulness to perceived design feature of survey-knowledge than the digital signage (M = 4.04, SD = 0.99), F(1, 30) = 5.76, MSe = 6.85, p < .05. Although the results did not support H3, they supported H2 and H4.

Figure 3. An interactive map of our system. TABLE IV. Design Guidelines x Visual cue on landmark x Exact, consistent and detailed information about destination

TABLE TYPE STYLES Design features

x x x x x x

x Visual/verbal guide of direction and route x Synergy with landmark design

x x x x

x Enhancing legibility (language & IA) x Well-organized and appropriate egocentric and exocentric information

x x x x x x x

x

x

RESULTS

Highlight landmark(s) Big real picture(s) of landmark(s) Showing landmark(s) on recommended route(s) Detailed information on destination “More information” button for detailed information Detailed information: explanation about building, brief directory Visual guide of route Highlight route to destination Real distance (“** meters”) or estimated time Verbal guide of direction at critical point of route above Showing bubble dialogues such as “turn right”, “across the street” Systematic ordering of directory Alphabetical order Systematic mapping Highlight building clicking its name & vice versa Egocentric view Accurate ‘current location’ position Picture(s) of buildings & street taken by street level Exocentric view - satellite map

a) Information quality: Guetzkow [39] found that information must be available systematically for the effective completion of required tasks. Effective communication through the availability of information is a vital component of collaboration [39, 40]. In the present study, information quality was operationalized as the degree of perceived quality of contents based on LRS (Landmark, Route, & Survey) knowledge. The level of perceived Information quality was measured with a scale in a post-test survey questionnaire that assesses the degree of information quality by asking participants to responds to 11 items. Of 11 questionnaire items, 3 items for landmark knowledge (Cronbach’s α=.87), 3 items for route knowledge (α=.77), and 5 items for survey

Figure 4. Mean and standard error of measurements.

V.

RESULTS

Participants who were new visitors in the university campus experienced the frustrating guide by existing print signage. Effectively designed signage on the basis of knowledge of wayfinding helped them understand the way to their destination

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better, satisfy with the new digital signage, and perceive it as useful. According to their verbal feedback, several participants explained that during navigation they had focused on the landmark buildings, not only the destination building itself but also other neighbored landmarks. Although existing printed signage also have visual information of buildings and landmarks according to the scale of the map, they do not attract new visitors who do not have any previous knowledge of the environment. Personalized and interactive way of displaying this landmark information can be major difference between print and digital signage. Showing visual and text information of the simulated route on the map is another main difference between existing print signage and new digital signage; print signage cannot fit to individualized need which digital signage can meet. Simple converting print signage into digital signage will not be affect navigators wayfinding performance. The effect of characteristics of digital signage such as personalizability and interactivity can be studied in the future. REFERENCES [1] R. R. Burke, "Behavioral effects of digital signage," J Advertising Res, vol. 49, pp. 180-185, 2009. [2] Q. Chen, F. Malric, Y. Zhang, M. Abid, A. Cordeiro, E. Petriu, and N. Georganas, "Interacting with digital signage using hand gestures," Image Analysis and Recognition, pp. 347-358, 2009. [3] J. V. Harrison and A. Andrusiewicz, "A virtual marketplace for advertising narrowcast over digital signage networks," Electronic Commerce Research and Applications, vol. 3, pp. 163-175, 2004. [4] L. I. Lundstrom, Digital signage broadcasting: content management and distribution techniques: Focal Pr, 2008. [5] J. Muller, D. Wilmsmann, J. Exeler, M. Buzeck, A. Schmidt, T. Jay, and A. Kruger, "Display Blindness: The Effect of Expectations on Attention towards Digital Signage," Pervasive Computing, pp. 1-8, 2009. [6] J. Schaeffler, Digital Signage: Focal Press, 2008. [7] J. Schaeffler, Digital Signage: Software, Networks, Advertising, and Displays: a Primer for Understanding the Business: Focal Press, 2008. [8] C. Dennis, A. Newman, R. Michon, J. Josko Brakus, and L. Tiu Wright, "The mediating effects of perception and emotion: Digital signage in mall atmospherics," Journal of Retailing and Consumer services, vol. 17, pp. 205-215, 2010. [9] A. Newman, C. Dennis, L. T. Wright, and T. King, "Shoppers’ Experiences of Digital Signage-a Cross-National Qualitative Study," International Journal of Digital Content Technology and its Applications, vol. 4, pp. 50-57, 2010. [10] A. D. Alonso and M. Bruce-Miller, "How Attractive is Wellington? A Study of Visitors to New Zealand's Capital City," Journal of Quality Assurance in Hospitality & Tourism, vol. 9, pp. 298-316, 2008. [11] J. H. Banning, "The Campus Ecologist Changes Format!," campusecologist.org, 1996. [12] G. Eaton, M. Vocino, and M. Taylor, "Evaluating signs in a university library," Collection management, vol. 16, pp. 81-101, 1993. [13] R. Passini, "Wayfinding design: logic, application and some thoughts on universality," Design Studies, vol. 17, pp. 319-331, 1996. [14] D. Appleyard, "Styles and methods of structuring a city," Environment and behavior, 1970. [15] K. Lynch, The image of the city: the MIT Press, 1960. [16] S. O. Tergan, "Digital concept maps for managing knowledge and information," Knowledge and information visualization, pp. 185-204, 2005. [17] R. M. Kitchin, M. Blades, and R. G. Golledge, "Understanding spatial concepts at the geographic scale without the use of vision," Progress in Human Geography, vol. 21, p. 225, 1997.

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