Veebi otsingumootorid ja vajadus keeruka informatsiooni järele

Väitekirja elektrooniline versioon ei sisalda publikatsioone.Veebi otsingumootorid on muutunud põhiliseks teabe hankimise vahenditeks internetist. Koos otsingumootorite kasvava populaarsusega on nende kasutusala kasvanud lihtsailt päringuilt vajaduseni küllaltki keeruka informatsiooni otsingu järele. Samas on ka akadeemiline huvi otsingu vastu hakanud liikuma lihtpäringute analüüsilt märksa keerukamate tegevuste suunas, mis hõlmavad ka pikemaid ajaraame. Praegused otsinguvahendid ei toeta selliseid tegevusi niivõrd hästi nagu lihtpäringute juhtu. Eriti kehtib see toe osas koondada mitme päringu tulemusi kokku sünteesides erinevate lihtotsingute tulemusi ühte uude dokumenti. Selline lähenemine on alles algfaasis ja ning motiveerib uurijaid arendama vastavaid vahendeid toetamaks taolisi informatsiooniotsingu ülesandeid. Käesolevas dissertatsioonis esitatakse rida uurimistulemusi eesmärgiga muuta keeruliste otsingute tuge paremaks kasutades tänapäevaseid otsingumootoreid. Alameesmärkideks olid: (a) arendada välja keeruliste otsingute mudel, (b) mõõdikute loomine kompleksotsingute mudelile, (c) eristada kompleksotsingu ülesandeid lihtotsingutest ning teha kindlaks, kas neid on võimalik mõõta leides ühtlasi lihtsaid mõõdikuid kirjeldamaks nende keerukust, (d) analüüsida, kui erinevalt kasutajad käituvad sooritades keerukaid otsinguülesandeid kasutades veebi otsingumootoreid, (e) uurida korrelatsiooni inimeste tava-veebikasutustavade ja nende otsingutulemuslikkuse vahel, (f) kuidas inimestel läheb eelhinnates otsinguülesande raskusastet ja vajaminevat jõupingutust ning (g) milline on soo ja vanuse mõju otsingu tulemuslikkusele. Keeruka veebiotsingu ülesanded jaotatakse edukalt kolmeastmeliseks protsessiks. Esitatakse sellise protsessi mudel; seda protsessi on ühtlasi võimalik ka mõõta. Edasi näidatakse kompleksotsingu loomupäraseid omadusi, mis teevad selle eristatavaks lihtsamatest juhtudest ning näidatakse ära katsemeetod sooritamaks kompleksotsingu kasutaja-uuringuid. Demonstreeritakse põhilisi samme raamistiku “Search-Logger” (eelmainitud metodoloogia tehnilise teostuse) rakendamisel kasutaja-uuringutes. Esitatakse sellisel viisil teostatud uuringute tulemused. Lõpuks esitatakse ATMS meetodi realisatsioon ja rakendamine parandamaks kompleksotsingu vajaduste tuge kaasaegsetes otsingumootorites.Search engines have become the means for searching information on the Internet. Along with the increasing popularity of these search tools, the areas of their application have grown from simple look-up to rather complex information needs. Also the academic interest in search has started to shift from analyzing simple query and response patterns to examining more sophisticated activities covering longer time spans. Current search tools do not support those activities as well as they do in the case of simple look-up tasks. Especially the support for aggregating search results from multiple search-queries, taking into account discoveries made and synthesizing them into a newly compiled document is only at the beginning and motivates researchers to develop new tools for supporting those information seeking tasks. In this dissertation I present the results of empirical research with the focus on evaluating search engines and developing a theoretical model of the complex search process that can be used to better support this special kind of search with existing search tools. It is not the goal of the thesis to implement a new search technology. Therefore performance benchmarks against established systems such as question answering systems are not part of this thesis. I present a model that decomposes complex Web search tasks into a measurable, three-step process. I show the innate characteristics of complex search tasks that make them distinguishable from their less complex counterparts and showcase an experimentation method to carry out complex search related user studies. I demonstrate the main steps taken during the development and implementation of the Search-Logger study framework (the technical manifestation of the aforementioned method) to carry our search user studies. I present the results of user studies carried out with this approach. Finally I present development and application of the ATMS (awareness-task-monitor-share) model to improve the support for complex search needs in current Web search engines

Does it matter which search engine is used? A user study using post-task relevance judgments

The objective of this research was to find out how the two search engines Google and Bing perform when users work freely on pre-defined tasks, and judge the relevance of the results immediately after finishing their search session. In a user study, 64 participants conducted two search tasks each, and then judged the results on the following: (1) The quality of the results they selected in their search sessions, (2) The quality of the results they were presented with in their search sessions (but which they did not click on), (3) The quality of the results from the competing search engine for their queries (which they did not see in their search session). We found that users heavily relied on Google, that Google produced more relevant results than Bing, that users were well able to select relevant results from the results lists, and that users judged the relevance of results lower when they regarded a task as difficult and did not find the correct information

CHORUS Deliverable 2.2: Second report - identification of multi-disciplinary key issues for gap analysis toward EU multimedia search engines roadmap

After addressing the state-of-the-art during the first year of Chorus and establishing the existing landscape in multimedia search engines, we have identified and analyzed gaps within European research effort during our second year. In this period we focused on three directions, notably technological issues, user-centred issues and use-cases and socio- economic and legal aspects. These were assessed by two central studies: firstly, a concerted vision of functional breakdown of generic multimedia search engine, and secondly, a representative use-cases descriptions with the related discussion on requirement for technological challenges. Both studies have been carried out in cooperation and consultation with the community at large through EC concertation meetings (multimedia search engines cluster), several meetings with our Think-Tank, presentations in international conferences, and surveys addressed to EU projects coordinators as well as National initiatives coordinators. Based on the obtained feedback we identified two types of gaps, namely core technological gaps that involve research challenges, and “enablers”, which are not necessarily technical research challenges, but have impact on innovation progress. New socio-economic trends are presented as well as emerging legal challenges

A knowledge based system for linking information to support decision making in construction

This work describes the development of a project model centred on the information and knowledge generated and used by managers. It describes a knowledge-based system designed for this purpose. A knowledge acquisition exercise was undertaken to determine the tasks of project managers and the information necessary for and used by these tasks. This information was organised into a knowledge base for use by an expert system. The form of the knowledge lent itself to organisation into a link network. The structure of the knowledge-based system, which was developed, is outlined and its use described. Conclusions are drawn as to the applicability of the model and the final system. The work undertaken shows that it is feasible to benefit from the field of artificial intelligence to develop a project manager assistant computer program that utilises the benefit of information and its link

Quantitative Analyses in Digital Marketing and Business Intelligence

This work is divided into two parts. The first part consists of four essays on questions in digital marketing; this term refers to all marketing activities on the Internet, regardless of whether they primarily address users of stationary devices (e.g., a desktop PC) or users of mobile devices (e.g., a smartphone). In Essay I, we model the time it takes until an item that is offered in the popular buy-it-now offer format is sold. Our model allows drawing inference from the observation of this time on how many consumers are interested in the item and on how much they value it. By this approach, several problems can be bypassed that often arise when these factors are estimated from data on items that are offered in an auction. We demonstrate the application of our model by an example. Essay II investigates which effects ads that are displayed on search engine results pages have on the click behavior and the purchase behavior of users. For this purpose, a model and a corresponding decision rule are developed and applied to a dataset that we have obtained in a field experiment. The results show that search engine advertising can be beneficial even for search queries for which the website of the advertising firm already ranks high among the regular, so-called organic search results, and even for users who already search with one of the firm’s brand names. In Essay III, we argue theoretically and show empirically that online product ratings by customers do not represent the rated product’s quality, as it has been assumed in previous studies, but rather the customers’ satisfaction with the product. Customer satisfaction does not only depend on product quality as observed after the purchase but also on the expectations the customers had of the product before the purchase. Essay IV investigates the relationship between the offline and the mobile content delivery channel. For this purpose, we study whether a publisher can retain existing subscribers to a print medium longer if he offers a mobile app through which a digital version of the print medium can be accessed. The application of our model to the case of a respected German daily newspaper confirms the existence of such an effect, which indicates a complementary relationship between the two content delivery channels. We analyze how this relationship affects the value of a customer to the publisher. The second part of this work consists of three essays that explore various approaches for simplifying the use of business intelligence (BI) systems. The necessity of such a simplification is emphasized by the fact that BI systems are nowadays employed for the analysis of more and more heterogeneous data than in the past, especially transactional data. This has also extended their audience, which now also includes inexperienced knowledge workers. Essay V analyzes by an experiment that we have conducted among knowledge workers from different firms how the presentation of data in a BI system affects how fast and how accurate the system users answer typical tasks. With regard to this, we compare the three currently most common data models: the multidimensional one, the relational one, and the flat one. The results show that it depends on the type of the task considered which of these data models supports users best. In Essay VI, a framework for the integration of an archiving component into a BI system is developed. Such a component can identify and automatically archive reports that have become irrelevant. This is in order to reduce the system users’ effort associated with searching for relevant reports. We show by a simulation study that the proposed approach of estimating the reports’ future relevance from the log files of the BI system’s search component (and other data) is suitable for this purpose. In Essay VII, we develop a reference algorithm for searching documents in a firm context (such as reports in a BI system). Our algorithm combines aspects of several search paradigms and can easily be adapted by firms to their specificities. We evaluate an instance of our algorithm by an experiment; the results show that it outperforms traditional algorithms with regard to several measures. The work begins with a synopsis that gives further details on the essays

Supporting Internet Search by Search-Log Publishing

Antud väitekiri on osa jätkuvast kollektiivsest uurimistööst, laiema eesmärgiga eeskätt parandada Internetiotsingu tuge keeruliste ja aeganõudvate ning tihti uurimusliku loomuga otsinguülesannete kiiremaks ja efektiivsemaks läbiviimiseks. Töö peamine uurimisprobleem on uut tüüpi otsinguülesannete logimise ja Internetis jagamise raamistiku väljatöötamine, olles alternatiiviks brauseri pistikprogrammide põhistele olemasolevatele meetoditele. Tegu oli keerulise insenertehnilise ülesandega, mille käigus tuli autoril täita mitmesuguseid programmeerimise, planeerimise, süsteemi komponentide integreerimise ja konfigureerimisega seotud ülesandeid. Püstitatud eesmärk sai edukalt täidetud. Väitekirjas pakuti välja proksipõhine meetod kasutajate otsingukäitumise logimiseks, mis on ühtlasi lihtsasti kohaldatav erinevatele veebilehitsejatele ning operatsioonisüsteemidele. Lahendust võrreldi varasemate sarnaste süsteemidega. Meetod sündis reaalsest vajadusest leida kergemalt hallatav ning porditav asendus varem väljatöötatud tarkvarale, mis kujutas endast pistikprogrammi Mozilla Firefox veebilehitsejale, kuid mida tuli parandada pärast iga uue brauseri versiooni väljatulekut. Teostus koosneb kahest suuremast komponendist, millest esimene ja tehniliselt keerulisem, otsinguülesannete logide koostamise ja jagamise süsteem, paikneb VirtualBox'i virtuaalses masinas. Teine on WordPress'il põhinev otsingulogide repositoorium, võimaldades lisaks kasutaja poolt annoteeritud logide avaldamise ka neist lihtsamaid otsinguid teostada. Süsteeme on põhjalikult testitud, kuid neid pole veel rakendatud Internetiotsinguga seotud kasutajauurimustesse. Autorile on teada, et selline huvi on olemas nii Tartu Ülikooli sees kui ka ühe välismaise partnerülikooli poolt. Lokaalselt paiknev otsinguülesannete koostamise ja jagamise süsteem koosneb kolmest võrdselt tähtsast alamkomponendist. Nendeks on Python'i keeles realiseeritud otsinguülesande logija; peamiselt PHP'd ja HTML'i kasutav veebiliides, mis muuhulgas võimaldab kasutajal eelpoolmainitud logijat sisse ja välja lülitada, aga ka kõiki otsinguülesandega seotud andmeid käsitsi muuta ja täiendada; ja antud ülesandeks spetsiaalselt konfigureeritud Privoxy veebiproksi server. Töös antakse põhjalik ülevaade olemasolevast tarkvarast, teaduspublikatsioonidest ja teoreetilistest alustest seoses väitekirja uurimisprobleemiga. Võrreldes olemasolevate meetoditega eristub autori pakutud proksipõhine otsinguülesannete logimise ja jagamise raamistik peamiselt kahel põhjusel. Esiteks, meetod tagab platvormist ja brauserist sõltumatuse, olles ühtlasi väga stabiilne. Teiseks, kasutajatele antav vabadus oma otsinguülesannet vabalt defineerida ning annoteerida on oluliseks uueks tähiseks. Väitekirja viimases peatükis käsitletakse tööga seotud tulevikuväljavaateid ja avatud probleeme. Üks neist on väljapakutavaga võrreldes muudetud arhitektuur, mis võimaldaks korraldada väiksema vaeva ja ajakuluga laborieksperimente. Internetiotsingu logimise süsteemi saab edasi arendada, lisades tuge enamatele JavaScript'i sündmustele. Otsingulogide repositoorium, olles veel üsna algeline, pakub hulgaliselt võimalusi täiendusteks tulevikuks.The main research problem of my thesis was engineering a new type of search task logging and publishing framework which would provide a better alternative for existing browser plug-in based methods. Right from the start, the proxy-based search task reporting system has been a complex engineering challenge involving code written in multiple programming languages, interactions planned across many software modules (some of which have already been existing large projects themselves), and a Linux operating system configured to ease the set-up process for the user. This was the decision process to make sure that this solution is reliable, extendible and maintainable in the future. My research goal was completed successfully. In my thesis, I proposed a proxy-based method for logging user search behaviour across different browsers and operating systems. I also compared it with an existing plug-in based Search Logger for Mozilla Firefox and other similar solutions. The idea of developing a proxy-based search task logging and publishing solution came from out of necessity, because the existing logging solution had significant problems with maintainability. The logs created by my solution are subsequently annotated by the user and made publicly available on a dedicated Internet blog called the Search Task Repository. Users can search against the already annotated and published Internet search logs. Ideally this would mean reduced complexity of search tasks for the users which in turn saves time. User studies to confirm this are still pending but there is confirmed interest from Tartu researchers as well as from one foreign university to use my solution in their search experiments. The proposed solution is comprised of two large units, which are the search task repository and the search task logging and publishing unit. The search task repository is a remote component, essentially a fairly simple WordPress blog, which enables search stories to be published automatically over XML-RPC protocol, search queries to be served, and search task logs to be displayed to the searcher. My logging system is configured as a VirtualBox virtual machine. It is much more complex, consisting of three sub-components: the main Web interface, the search task logger, and the Privoxy Web proxy specially configured for my needs. Logging can be started and stopped at a user's will in the main Web interface. What is more, this sub-component also gives them absolute control over what gets published online by providing an editing and annotating functionality for all search task data, both implicitly and explicitly logged. A comprehensive theoretical overview was given in my thesis about the state of the art, explaining basic related concepts in Information Retrieval and recent developments in Exploratory Search and search task logging systems. In contrast with existing browser plug-in based search task logging methods, my proposed proxy-based approach ensures platform and browser independence while also being very stable. By giving searcher's the opportunity to freely define and annotate their own search tasks, my search support solution is setting a new standard. In the final chapter, I conducted a thorough analysis about future work and presented my own vision about the future opportunities for this search support methodology. A modified architecture for more convenient laboratory experiments was outlined as an important task for the future. In conclusion, my proxy-based search task logging, editing and publishing framework can be extended further to log more JavaScript events. The search task repository is a large open area with lots of opportunities for future extensions

CBR and MBR techniques: review for an application in the emergencies domain

The purpose of this document is to provide an in-depth analysis of current reasoning engine practice and the integration strategies of Case Based Reasoning and Model Based Reasoning that will be used in the design and development of the RIMSAT system. RIMSAT (Remote Intelligent Management Support and Training) is a European Commission funded project designed to: a.. Provide an innovative, 'intelligent', knowledge based solution aimed at improving the quality of critical decisions b.. Enhance the competencies and responsiveness of individuals and organisations involved in highly complex, safety critical incidents - irrespective of their location. In other words, RIMSAT aims to design and implement a decision support system that using Case Base Reasoning as well as Model Base Reasoning technology is applied in the management of emergency situations. This document is part of a deliverable for RIMSAT project, and although it has been done in close contact with the requirements of the project, it provides an overview wide enough for providing a state of the art in integration strategies between CBR and MBR technologies.Postprint (published version

Discovering real-world usage scenarios for a multimodal math search interface

To use math expressions in search, current search engines require knowing expression names or using a structure editor or string encoding (e.g., LaTeX) to enter expressions. This is unfortunate for people who are not math experts, as this can lead to an intention gap between the math query they wish to express, and what the interface will allow. min is a search interface that supports drawing expressions on a canvas using a mouse/touch, keyboard and images. We designed a user study to examine how the multimodal interface of min changes search behavior for mathematical non-experts, and discover real-world usage scenarios. Participants demonstrated increased use of math expressions in queries when using min. There was little difference in task success reported by participants using min vs. text-based search, but the majority of participants appreciated the multimodal input, and identified real-world scenarios in which they would like to use systems like min

A Usability Approach to Improving the User Experience in Web Directories

Submitted for the degree of Doctor of Philosophy, Queen Mary, University of Londo

Computer detection of spatial visualization in a location-based task

An untapped area of productivity gains hinges on automatic detection of user cognitive characteristics. One such characteristic, spatial visualization ability, relates to users’ computer performance. In this dissertation, we describe a novel, behavior-based, spatial visualization detection technique. The technique does not depend on sensors or knowledge of the environment and can be adopted on generic computers. In a Census Bureau location-based address verification task, detection rates exceeded 80% and approached 90%