There are two main ways to retrieve files: hierarchical navigation and query-based search. File retrieval studies have consistently found navigation preference, with search used only as a last resort when users forget in which folder they stored the target file. However, a minority of people, referred to as hyper-searchers, perform far more searches than others. This study aimed to discover why hyper-searchers conduct searches far more than the rest of the population. To do so, a group of hyper-searchers (n = 50) and a control group (n = 50) were assigned using a double-check allocation method which included both self-estimation and a retrieval task. On average, the search percentage in the retrieval task for the hyper-searchers (67%) was over 13 times higher than for the control group (5%). The study gives ample evidence that hyper-searchers’ files were less organized than the control group. As a result, their average navigation failure percentage (23%) was almost 4 times higher than the control group (6%), and hyper-searchers needed to resort to search. Our results suggest that hyper-searchers’ files were less well-organized because they scored less on the conscientiousness trait of the Big Five personality questionnaire; and in turn, having less organized files forced them to search more.

This introduction discusses the background and motivations for this special issue on Personal Information Management (PIM). We summarize accepted papers and outline future issues for PIM research.

Abstract This study sheds light on the disparities between file search beliefs and as opposed to file search behavior. Using a questionnaire (N = 110), we measured participants’ intuitive beliefs regarding query-based search usage and compared it to well-validated scientific findings. Our participants believed that search is the dominant retrieval strategy; search engine technology strongly increases search usage and will eventually eliminate folder navigation; and that young people search more than older ones. Contrary to these beliefs, research has shown that users prefer folder-based navigation, with search being used only as a last resort for a small minority of retrievals; search engine technology has little effect on search usage or folder organization; folder navigation has deep neuro-cognitive roots and there is a positive correlation between age and search percentage. We then discuss possible reasons for these contrasts and conclude that evidence-based personal information management education should be used to correct these baseless beliefs.

Abstract File sharing is an integral component of modern work. Files can be shared either using Group Information Management (GIM), where collaborators exploit a common repository (e.g., the cloud), or Personal Information Management (PIM), where files are sent via email attachments, and collaborators store files individually in personal collections. Given the recent prevalence of GIM, we compare the effects on retrieval for PIM versus GIM collections. We examine the effects of various theoretically motivated factors relating to collection size, properties of the target file, and user workload. In our study, 289 participants accessed 1,557 of their own shared files in a naturalistic setting. Results indicate that factors relating to collection size, file versions, and user workload negatively affect the retrieval of GIM more than PIM files, indicating that PIM is more scalable than GIM. Testing a very different population, we confirm previous findings that failure percentages of GIM are approximately double those of PIM. We discuss possible theoretical explanations, specifically how factors that hinder retrieval exacerbate the general GIM problem of retrieving files organized by other people. Overall, PIM's greater scalability has practical implications for fast‐growing organizations such as startups when choosing their sharing policies.

Upgrades are a common experience for people who use technology for any length of time. Upgrades may bring clear benefits, and some users look forward to new versions of software. However for others, upgrades may be a burden. Upgrades bring costs, imposing a need to refamiliarize ourselves with a new version after mastering the old one. It is important to understand such costs as failure to upgrade can make users vulnerable to security risks. We first review multiple studies showing users' dislike of upgrades resulting from changes introduced to the interface. Then we propose a framework to analyze the nature of upgrade costs, explaining their origins using well-validated cognitive psychology concepts including: cognitive automation, negative transfer, cognitive maps, procedural memory and locus of control. We use these concepts to explain the psychological costs of frequent interface changes while sketching some approaches to addressing them. Although new versions are necessary for progress, this paper provides software developers with a deeper understanding of the sometimes overlooked costs of frequent interface changes.

The recent version problemrelates to finding the latest version of a file to avoid reconciliation and rework resulting from editing an out of date version. To identify the most recent version, we developed a prototype, Old'nGray, which automatically grays out the icon of older versions of the file to help users ignore them and spot the latest version using perceptual rather than cognitive processes. We tested our prototype using a within-subjects design (n=60). Use of Old'nGray drastically reduced failure percentage from an average of 24% in the control condition to 4%, and retrieval time from an average of 17.68 s in the control condition to 6.56 with Old'nGray. The benefits of Old'nGray increased with folder size. Chronological sorting was used in only half of the control condition retrievals, which may explain the high failure percentage. The use of chronological sorting also resulted in additional retrieval time compared with the use of Old'nGray. When asked, 70% of the participants indicated that they would like the prototype to be integrated into their next operating system.

People who are collaborating can share files in two main ways: performing Group Information Management (GIM) using a common repository or performing Personal Information Management (PIM) by distributing files as e‐mail attachments and storing them in personal repositories. There is a trend toward using common repositories with many organizations encouraging workers to use GIM to avoid duplication of files and management. So far, PIM and GIM have been studied by different research communities, so their effectiveness for file retrieval has not yet been systematically compared. We compared PIM and GIM in a large‐scale elicited personal information retrieval study. We asked 275 users to retrieve 860 of their own shared files, testing the effect of sharing method on success and efficiency of retrieval. Participants preferred PIM over GIM. More important, PIM retrieval was more successful: Participants using GIM failed to find 22% of their files compared with 13% failures using PIM. This may be because active organization aids retrieval: When using personally created folders, the failure percentage was 65% lower than when using default folders (e.g., My Documents), and more than 5 times lower than when using folders created by others for GIM. Theoretical reasons for this are discussed.

Users’ preferences for folders versus tags was studied in 2 working environments where both options were available to them. In the Gmail study, we informed 75 participants about both folder‐labeling and tag‐labeling, observed their storage behavior after 1 month, and asked them to estimate the proportions of different retrieval options in their behavior. In the Windows 7 study, we informed 23 participants about tags and asked them to tag all their files for 2 weeks, followed by a period of 5 weeks of free choice between the 2 methods. Their storage and retrieval habits were tested prior to the learning session and, after 7 weeks, using special classification recording software and a retrieval‐habits questionnaire. A controlled retrieval task and an in‐depth interview were conducted. Results of both studies show a strong preference for folders over tags for both storage and retrieval. In the minority of cases where tags were used for storage, participants typically used a single tag per information item. Moreover, when multiple classification was used for storage, it was only marginally used for retrieval. The controlled retrieval task showed lower success rates and slower retrieval speeds for tag use. Possible reasons for participants’ preferences are discussed.

Folder navigation is the main way that computer users retrieve their personal files. However we know surprisingly little about navigation, particularly about how it is affected by the operating system used, the interface presentation and the folder structure. To investigate this, we asked 289 participants to retrieve 1,109 of their own active files. We analyzed the 4,948 resulting retrieval steps, i.e. moves through the hierarchical folder tree. Results show: (a) significant differences in overall retrieval time between PC and Mac that arise from different organizational strategies rather than interface design; (b) the default Windows presentation is suboptimal - if changed, retrieval time could be reduced substantially and (c) contrary to our expectations, folder depth did not affect step duration. We discuss possible reasons for these results and suggest directions for future research.

Lifelogging is a technically inspired approach that attempts to address the problem of human forgetting by developing systems that ‘record everything’. Uptake of lifelogging systems has generally been disappointing, however. One reason for this lack of uptake is the absence of design principles for developing digital systems to support memory. Synthesising multiple studies, we identify and evaluate 4 new empirically motivated design principles for lifelogging: Selectivity, Embodiment, Synergy and Reminiscence. We first summarise 4 empirical studies that motivate the principles, then describe the evaluation of 4 novel systems built to embody these principles. The design principles were generative, leading to the development of new classes of lifelogging system, as well as providing strategic guidance about how those systems should be built. Evaluations suggest support for Selection and Embodiment principles, but more conceptual and technical work is needed to refine the Synergy and Reminiscence principles.

People are often required to catch up on information they have missed in meetings, because of lateness or scheduling conflicts. Catching up is a complex cognitive process where people try to understand the current conversation without access to prior discussion. We develop and evaluate a novel Catchup audio player that allows time-travel. It automatically identifies the gist of what was missed, allowing people to join the meeting late and still participate effectively. In a lab study, we evaluated people's understanding of meetings they had partly missed, by asking questions about meeting content. We tested whether providing Catchup gist overcomes the potential disadvantage that people must join even later - because catching up takes time. Catchup users understood meetings 70% better than controls who simply joined late. They were more confident of their understanding and indicated a positive attitude towards the tool. We are currently exploring more general applications of the time-travel approach.

Abstract Folder navigation is the main way that personal computer users retrieve their own files. People dedicate considerable time to creating systematic structures to facilitate such retrieval. Despite the prevalence of both manual organization and navigation, there is very little systematic data about how people actually carry out navigation, or about the relation between organization structure and retrieval parameters. The aims of our research were therefore to study users' folder structure, personal file navigation, and the relations between them. We asked 296 participants to retrieve 1,131 of their active files and analyzed each of the 5,035 navigation steps in these retrievals. Folder structures were found to be shallow (files were retrieved from mean depth of 2.86 folders), with small folders (a mean of 11.82 files per folder) containing many subfolders (M=10.64). Navigation was largely successful and efficient with participants successfully accessing 94% of their files and taking 14.76 seconds to do this on average. Retrieval time and success depended on folder size and depth. We therefore found the users' decision to avoid both deep structure and large folders to be adaptive. Finally, we used a predictive model to formulate the effect of folder depth and folder size on retrieval time, and suggested an optimization point in this trade‐off.

Users find it hard to delete unimportant personal information which often results in cluttered workspaces. We present a full design cycle for GrayArea, a novel interface that allows users to demote unimportant files by dragging them to a gray area at the bottom of their file folders. Demotion is an intermediate option between keeping and deleting. It combines the advantages of deletion (unimportant files don't compete for attention) and keeping (files are retrieved in their folder context). We developed the GrayArea working prototype using thorough iterative design. We evaluated it by asking 96 participants to 'clean' two folders with, and without, GrayArea. Using GrayArea reduced folder clutter by 13%. Further, 81% of participants found it easier to demote than delete files, and most indicated they would use GrayArea if provided in their operating systems. The results provide strong evidence for the demotion principle suggested by the user-subjective approach.

Abstract Personal Information Management (PIM) is an activity in which an individual stores personal information items to retrieve them later. In a former article, we suggested the user‐subjective approach, a theoretical approach proposing design principles with which PIM systems can systematically use subjective attributes of information items. In this consecutive article, we report on a study that tested the approach by exploring the use of subjective attributes (i.e., project, importance, and context) in current PIM systems, and its dependence on design characteristics. Participants were 84 personal computer users. Tools included a questionnaire (N = 84), a semistructured interview that was transcribed and analyzed (n = 20), and screen captures taken from this subsample. Results indicate that participants tended to use subjective attributes when the design encouraged them to; however, when the design discouraged such use, they either found their own alternative ways to use them or refrained from using them altogether. This constitutes evidence in support of the user‐subjective approach as it implies that current PIM systems do not allow for sufficient use of subjective attributes. The article also introduces seven novel system design schemes, suggested by the authors, which demonstrate how the user‐subjective principles can be implemented.

Traditionally users access their personal files mainly by using folder navigation. We evaluate whether recent improvements in desktop search have changed this fundamental aspect of Personal Information Management (PIM). We tested this in two studies using the same questionnaire: (a) The Windows Studya longitudinal comparison ofGoogle DesktopandWindows XP Search Companion, and (b) The Mac Studya large scale comparison of MacSpotlightandSherlock. There were few effects for improved search. First, regardless of search engine, there was a strong navigation preference: on average, users estimated that they used navigation for 56-68% of file retrieval events but searched for only 4-15% of events. Second, the effect of improving the quality of the search engine on search usage was limited and inconsistent. Third, search was used mainly as a last resort when users could not remember file location. Finally, there was no evidence that using improved desktop search engines leads people to change their filing habits to become less reliant on hierarchical file organization. We conclude by offering theoretical explanations for navigation preference, relating to differences between PIM and Internet retrieval, and suggest alternative design directions for PIM systems.

The project fragmentation problem in personal information management occurs when someone who is working on a single project stores and retrieves information items relating to that project from separate format-related collections (documents, emails and favorite Web sites). This study was aimed to test empirically users' working habits in order to shed light on the project fragmentation problem. Twenty personal computer users participated in the study. Data collection tools included an interview, screen captures and a questionnaire. Results indicate that users tend to store and retrieve project-related information items based on different formats in one project folder when the interface design encourages it. However, they store and retrieve project- related information items in different folders (documents, emails and favorite Web sites) when the design encourages such fragmentation. Two types of attempts to solve the project fragmentation problem are reviewed and a new possible solution is suggested.

Abstract In this article we suggest a user‐subjective approach to Personal Information Management (PIM) system design. This approach advocates that PIM systems relate to the subjective value‐added attributes that the user gives to the data stored in the PIM system. These attributes should facilitate system use: help the user find the information item again, recall it when needed, and use it effectively in the next interaction with the item. Driven from the user‐subjective approach are three generic principles which are described and discussed: (a) The subjective classification principle, stating that all information items related to the same subjective topic should be classified together regardless of their technological format; (b) The subjective importance principle, proposing that the subjective importance of information should determine its degree of visual salience and accessibility; and (c) The subjective context principle, suggesting that information should be retrieved and viewed by the user in the same context in which it was previously used. We claim that these principles are only sporadically implemented in operating systems currently available on personal computers, and demonstrate alternatives for interface design.