Sinch: Delegating Web Search from a Mobile Device ABSTRACT situations is far more fragmented and subject to interruption Sinch is an application that allows mobile device users to than on the desktop [11,15]. obtain answers to their questions without having to perform One solution is delegated search: asking other people to a web search in their mobile browser. Questions are answered by workers on Mechanical Turk, an online labor find the answer for you. For example, ChaCha market for simple human computation tasks. Workers on (chacha.com) accepts questions by text message or through Mechanical Turk can search for answers using their desktop a phone app, and a ChaCha employee finds the answer and browsers, who, unlike the mobile user, are free from the returns it by text message. Another source of delegation is an online social network, either mediated by a service like numerous shortcomings of browsing the web on a small mobile device while in a potentially distracting situation. Aardvark (vark.com) or simply asking questions through Sinch contributes a URL-rewriting proxy browser that can status updates [14]. Systems such as PlayByPlay [18] and be embedded in Mechanical Turk tasks to track browsing SearchTogether [13] focus on collaborative search or history, text selections, and other user events. It also browsing between close friends or colleagues. introduces two ways to improve the credibility of human- generated answers: providing multiple answers to the same question and including a browsing history with each (a) answer. The Sinch application also allows users to view (b) evidence for answers in their original context on a web page, using a custom mobile browser to highlight the answer text on the web page and zoom into it. Evaluations demonstrate that Sinch is capable of delivering correct answers in a timely manner and investigate the effectiveness of providing multiple answers and a browsing history for each answer. Author Keywords ACM Classification Keywords H5.m. Information interfaces and presentation (e.g., HCI): Miscellaneous. (c) (d) INTRODUCTION Mobile users have information needs [17] that can often be answered by web searching, but even with modern smartphones, web browsing poses challenges for mobile users: small screens, “fat fingers,” slow or intermittent network connections, and distractions caused by walking, driving, and other mobile activities. Attention in mobile Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Figure 1: The Sinch phone app in action: (a) asking a CHI 2011, May 7–12, 2011, Vancouver, BC, Canada. question; (b) viewing received answers; (c) viewing the Copyright 2011 ACM 978-1-4503-0267-8/11/05...$5.00. browsing history for an answer; (d) viewing a web page with the copied answer highlighted in context. (a) (b) Figure 2: Question-answering interface used by MTurk workers: (a) starting view with a question to answer; (b) after the worker has found the answer, selected it in the web page, and copied it to the answer textbox. This paper explores another resource for delegated search: a because they may help answer follow-up questions in crowd for hire, such as that found on Amazon Mechanical addition to the user’s original query. Turk. Crowd workers can be highly available (compared to We evaluated Sinch with two studies. The first experiment more limited populations like friends) and have greater evaluated the question-answering backend by posting ability to access the web from their desktops than the simulated questions on Mechanical Turk, to measure mobile user. latency and error rate. It found that crowd workers This paper describes Sinch, a new system that provides answered typical questions in less than 3 minutes on delegated search from a mobile phone using searchers hired average, and if 10 workers were recruited, then a correct on-demand on Amazon Mechanical Turk (MTurk). With answer could often be obtained in less than a minute. The Sinch, a mobile user speaks a question into a smartphone. second experiment tested the mobile phone frontend in a Several MTurk workers are recruited to search for the lab user study, in which participants not only asked their answer on the web. Their answers are delivered back to the own questions and received live answers, but also reviewed user’s phone, along with the browsing history used to find answers to canned questions. By manipulating the number the answer, which was automatically collected while the of answers returned and the presence or absence of worker was searching. The web page on which the worker browsing history, this study found that both factors had a found the answer is marked, and the phone automatically significant and strong effect on the user’s confidence in the zooms and pans the web page to show that answer in correctness of an answer. context. Figure 1 shows the Sinch application in action. The contributions of this paper are: (1) a system design that Key research questions about delegated search are latency hires crowd workers on demand for delegated searching and (how fast do answers come back, since mobile questions collects their browsing history automatically; (2) an may be time-sensitive) and correctness (does the mobile evaluation measuring the latency, correctness, and behavior user get the right answer, or at least a useful one). Sinch of crowd searchers; and (3) an evaluation showing the addresses the latency question using techniques pioneered benefit of browsing history and multiple answers for by VizWiz [3] to have workers warmed up and ready to increasing the end-user’s confidence in delegated searches. answer questions. It addresses correctness in two ways: by The next section covers related work. We then present a obtaining answers from multiple workers, and by including scenario of Sinch in action, and describe the system in more the list of web pages consulted by the workers with each detail: the phone user interface and the backend answer– answer, so that the mobile user can judge the quality of the generation system on MTurk. We then present the two answer. Including the web pages has another benefit, experiments, discuss the advantages and limitations of this approach as revealed by the experiments, and conclude. RELATED WORK the search, often to help refine the search [5]. While Sinch A significant body of work addresses delegated search and doesn’t allow for interaction to refine queries, providing similar question and answer systems. First we address browsing history can function as a refinement mechanism. commercial systems that fill a similar role. VizWiz [3] allows blind users to ask visual questions by ChaCha (chacha.com) is a delegated search service that taking a picture with a smartphone and sending it (with a accepts questions through SMS text message, Android and spoken question) to a crowd. VizWiz’s motivation is iPhone apps, and a website, and routes them to a similar to Sinch – where VizWiz helps visually-impaired previously-hired workforce of “ChaCha Guides.” For the users, Sinch aims to help users who are situationally phone apps and website, questions are first matched against disabled by mobility. Both systems also obtain multiple a repository of canned questions and answers, which often answers from the crowd to improve quality, and Sinch uses include links to source web pages. When a live searcher techniques pioneered by VizWiz to reduce latency. answers a question, however, ChaCha returns a single text- However, Sinch is targeted at web-based information, and only answer. By comparison, Sinch explores the benefits of automatically captures and conveys browsing history. hiring searchers on demand, obtaining multiple answers, and obtaining browsing history from each searcher. USAGE SCENARIO This section illustrates a scenario where Sinch can be used. Other question-answering services (such as Yahoo Michael is at a beach with his family during the weekend, Answers, Mahalo, Aardvark, Quora, and Facebook along with his new Nikon D90 camera. He takes a few Questions) focus on questions that are hard to find with shots, but it looks like something is wrong with aperture. search engines, that need an answer from an expert, or that Having limited experience with his camera, he wants to are not serious questions. Sinch is designed to support search for useful information on the web, but not spend 10 mobile users with questions that would normally be easy to minutes looking at the smartphone screen under the sun, search from a desktop. Harper et al. note that informational reading pages of technical documentation. Also, he needs to questions have higher archival value and are treated more keep an eye on his children swimming in the water. He seriously [6], supporting design decisions for Sinch. A decides to use Sinch. study of Aardvark found that only 9.1% of Aardvark When he launches the Sinch application on his phone, he is answers include hyperlinks [8], whereas 100% of Sinch prompted to enter a question. Tapping the microphone answers have supporting web pages. button, Michael speaks his question, "How do you adjust Interesting systems work in recent research includes mimir, aperture in Nikon D90?" After making sure that his which looked at market mechanisms’ influence on question was correctly recognized, he submits it. responses [9]. They found incentivizing participation to While he talks to his wife and looks at their children decrease low-quality responses, a design strategy that Sinch swimming, Sinch automatically posts HITs on MTurk with employs through its use of Mechanical Turk.