Tuesday, September 27, 2011

Gang Leader for a day

Gang Leader for a Day by Sudhir Venkatesh was a very unique piece of literature that I have come across so far. I got introduced to the concept of Ethnography for the first time in the HCI course and I found this book to be a wonderful source of knowledge about Ethnography. I had difficulty not drifting off into taking this entire information piece as a fiction story, while reading the book.
The reason this booked appealed to me in the very beginning was the author's dedication and passion for his work. After reading the chapter where the author just goes into the African American restricted community and starts interviewing the residents there, I kept getting more and more curious about how he managed to escape from the situations. This book was a very good eye-opener as it shows how the most "dangerous" people have a good side somewhere within them. I always had a mindset that actions form habits and habits in-turn form people, and that there is no way to change people if they don't have the right habits. After reading this book, I noticed how J.T. , being the leader of the Black Kings, showed signs of liking for the life that was completely opposite of his.

The most vital and interesting thing I learned from this book was the fact how there was the concept of a community organization within the Black King gang, and how people worked together for survival, even in the most adverse conditions.

Blog #12: Multitoe: High-Precision Interaction with Back-Projected Floors Based on High-Resolution Multi-Touch Input

Paper Title: Multitoe: High-Precision Interaction with Back-Projected Floors Based on High-Resolution Multi-Touch Input


Authors: Thomas Augsten, Konstantin Kaefer, Rene Meusel, Caroline Fetzer, Dorian Kanitz, Thomas Stoff, Torsten Becker, Christian Holz and Patrick Baudisch


Author Bios:
Thomas Augsten is pursuing Masters in IT Systems at the University of Potsdam in Germany.


Konstantin Kaefer is pursuing Masters in IT Systems at the University of Potsdam in Germany.


Rene Meusel is a student at the Hasso Plattner Institute.


Caroline Fetzer is a student at the Hasso Plattner Institute.


Dorian Kanitz is a student at the Hasso Plattner Institute.


Thomas Stoff is a student at the Hasso Plattner Institute.


Torsten Becker is a student at the Hasso Plattner Institute.


Christian Holz is a student at the University of Potsdam pursuing a Ph.D. in HCI.


Patrick Baudisch is a student at the University of Potsdam pursuing a Ph.D. in HCI.




Presentation Venue: This paper was presented at UIST '10 Proceedings of the 23rd annual ACM symposium on User interface software and technology in New York.


Summary:
Hypothesis: The authors here propose creating direct touch surfaces that are orders of magnitude larger. They approach this challenge by integrating high-resolution multitouch input into a back-projector floor. At the same time, they maintain the purpose and interaction concepts of tabletop computers, namely direct manipulation. They have based their hardware design on frustrated total internal reflection. The prototype's ability to sense per-pixel pressure allows the floor to locate and analyze user's soles. They demonstrate how this allows the floor to recognize foot postures and identify users. These two functions form the basis of the systems of their prototype. They allow the floor to ignore users unless they interact explicitly, identify and track users based on their shoes, enable high-precision interaction, invoke menus, track heads, and allow users to control high-degree of freedom interactions using their feet. 
How the hypothesis was tested: The authors tested their prototype by performing multiple experiments using participants.
How to not activate a button: This study was performed to help design a mechanism that allowed the floor to distinguish intentional user action from regular walking and standing (intuition). Te interface was implemented using four paper buttons taped to the floor. The participants walked across the four buttons and were tasked to "activate" the two 'cancel' buttons and get across the 'ok' buttons without activating them.
Participants: 30 --> 6 female 24 male
Results: Tapping for activation



Invoking a menu: Maximum number of participants used the "jump" action to invoke a menu


Conceptual model of stepping: This study was performed to understand which area of the user soles are active and should be thus considered in hit testing. For this experiment, the participants stepped onto the multi-touch floor with their dominant foot wearing shoes.
Participants: 20 --> 6 female 14 male
Results: 8 of 20 participants set every button at least a certain percentage of which was covered by the projection of the participant's shoe.


High-Precision Pointing with Hotspot: The purpose of this study was to survey what point on the users' shoe (hotspot) was used to interact with point targets. Participants wearing shoes stood on a waiting position marked with circles. For each trial, a target marked with crosshairss appeared 30cm in front of the user. Users placed their preferred foot onto the crosshairs, such that the foot's hotspot was located directly over the crosshairs.




Discussion:
Effectiveness: In this paper the authors presented high-resolution FTIR (Frustrated total internal reflection)- based floors  as a means to create interactive multi-touch surfaces beyond the size of tabletop computers. They made first steps toward enabling the interaction model of touch (direct manipulation) on such a floor. Combining high-resolution FTIR with a projected floor also resulted in the design of additional interactions. One of them is user identification based on sole patterns. 
Reasons for being Interesting: This paper is really interesting to me as the authors perform multiple tests on the participants and contribute those results to develop algorithms  that would make it possible for the users to control input devices keeping their hands free.
Faults: There are no reported faults in this paper since the prototype is using algorithms using the user participation survey. However, I personally think that this idea is very effective for controlling tasks like playing music, selecting songs, forwarding then, selecting pictures etc. However, a function such as typing using one's foot would result in a strenuous physical activity as compared to efficiently inputting data on a given space.

Monday, September 26, 2011

Blog #11: Enabling Beyond-Surface Interactions for Interactive Surface with An Invisible Projection


Paper Title: Enabling Beyond-Surface Interactions for Interactive Surface with An Invisible Projection


Authors: Li-Wei Chan, Hsiang-Tao Wu, Hui-Shan Kao, Ju-Chun Ko, Home-Ru Lin, Mike Y. Chen, Jane Hsu and Yi-Ping Hung 


Author Bios: 
Li-Wei Chan is a Ph.D student in Image and Vision Lab and iAgent Lab at Graduate Institute of Networking and Multimedia, National Taiwan University in Taiwan. He received his masters and bachelors degree in Computer Science from National Taiwan University in 2004 and from Fu Jen Catholic University in 2002, resp.


Hsiang-Tao Wu is a Ph.D student at Graduate Institute of Networking and Multimedia, National Taiwan University in Taiwan.


Hui-Shan Kao is a student at Graduate Institute of Networking and Multimedia, National Taiwan University in Taiwan.


Home-Ru Lin is a student at Graduate Institute of Networking and Multimedia, National Taiwan University in Taiwan.


Ju-Chun Ko is a Ph.D student at Graduate Institute of Networking and Multimedia, National Taiwan University in Taiwan.


Mike Chen has a profession in the department of computer science at the National Taiwan University.


Jane Hsu is currently a professor at the National Taiwan University in the Computer Science and Information Engineering department.


Yi-Ping Hung is a professor at the National Taiwan University at the Graduate Institute of Networking and Multimedia.




Presentation Venue: This paper was presented at UIST '10 Proceedings of the 23rd annual ACM symposium on User interface software and technology in New York.


Summary:
Hypothesis: This paper presents a programmable infrared (IR) technique that utilizes invisible, programmable markers to support interaction beyond the surface of a diffused-illumination (DI) multi-touch system. The authors combine an IR projector and a standard color projector to simultaneously project visible content and invisible markers. The mobile devices outfitted with IR cameras can compute their 3D positions based on the markers perceived. Markers are selectively turned off to support multi-touch and direct on-surface tangible input. The proposed techniques enable a collaborative multi-display multi-touch tabletop system. The authors also present three interactive tools: i-m-View, i-m-Lamp and i-m-Flashlight, which consists of a mobile tablet and projectors that users can freely interact with, beyond the main display surface.
How the hypothesis was tested: The hypothesis was tested by providing three example applications that took advantages of the proposed techniques to provide intuitive and natural manipulation:
i-m-Lamp: a desk lamp for tabletops

The i-m-Lamp is composed of a pico-projector attached to an IR camera, mimicking the use of a desk lamp for the laptop system. i-m-Lamp provides a solution for multi-resolution that delivers fine details of the content right below the lamp while the overall view of the content is given by the tabletop system. Users can simply manipulate the lamp to  move the high-resolution projection anywhere on teh tabletop without memorizing any gestures. It is very suitable for integration with a personal tabletop system as a working desk.
i-m-Flashlight: a mobile exploration tool

This is a mobile version of the i-m-Lamp designed as an intuitive interface for applications of information exploration. The operations for i-m-Flashlight imitate the use of a handheld flashlight. Users can inspect the fine details of a region of interest by simply focusing the i-m-Flashlight toward that direction. In comparison, i-m-Flashlight facilitates short-term exploration activities where users can quickly explore multiple regions in the projection display. This is used as the interface to appreciate rich details in digital paintings.
i-m-View: an intuitive 3D viewer
i-m-View is composed of a tablet computer attached to an IR camera, featuring an intuitive viewer to explore 3D geographical information. The concept has been proposed and implemented in meraDesk, where a magnetic-field position sensor is used to track an arm-mounted monitor in six degrees of freedom. The i-m-View can be immersive, isolating the user from other users around the table, and from the table system.


This prototype system is composed of a table system and several mobile devices (the three listed above) connected with the table. The table system prototype is implemented on a standard desktop computer. The authors conducted early user testing in order to understand the strengths and limitations of the prototype. The users were told to freely use the three devices available for testing in turn. The task was to navigate the famous buildings and annotated photos shown on the map. Each photo in the table projection is presented as a pin on the map. With i-m-Lamp and i-m-Flashlight, users could see the photo beneath the pin. Therefore, the users had to drag the map or move the  i-m-Lamp or i-m-Flashlight to highlight the pins and to browse through the photos.
Result: All users reported mostly positive feedback regarding the i-m-Lamp. The focus problem was an issue face in the i-m-Flashlight/ This is because i-m-Lamp, when in regular use, is usually at an appropriate distance from the table surface and can hence present a sharp projection. i-m-Flashlight suggers from a severe focus problem, as users tend to move it quickly around, and use it from a wide range of proximities from the table surface.


Discussion:
Effectiveness: This paper presents a new interactive tabletop system that enables interaction beyond the surface using invisible markers while supporting multi-touch and tangible input directly on the surface. Mobile devices outfitted with IR cameras can compute their 3D positions based on the markers perceived. Markers are selectively turned off to support multi-touch and direct on-surface tangible input. The prototype is an excellent way to project a 3D view of things being projected on a surface. It has a few problems but considering the everyday objects that they are using to project this 3D view, I think it is an excellent prototype.
Reasons for being Interesting: This prototype provides various features by using everyday devices that are used at home. For e.g. the i-m-Lamp that is proposed by the authors provides a solution for multi-resolution that delivers fine details of the content right below the lamp and also the overall view of the content is given by the tabletop system. Also, the i-m-Flashlight is used as the interface to appreciate rich details in digital paintings.
Faults: The 3M LCD-based projectors that were used by the authors for the i-m-Lamp and the i-m-Flashlight devices, have lens that need to be manually adjusted to obtain sharp projections. This manual process limits the feasibility of mobile projection applications.


Interesting link: http://www.youtube.com/watch?v=jVwsgZ7ckxk

Wednesday, September 21, 2011

Blog #10: Sensing Foot Gestures from the Pocket

Paper Title: Sensing Foot Gestures from the pocket


Authors: Jeremy Scott, David Dearman, Koji Tatani, and Khai N. Truong


Author Bios:

Jeremy Scott received his B.Sc., M.Sc. and PhD. in Pharamcology and Toxicology from the University of Western Ontario. He is currently an Assistant Professor and a Research Scientist at the University of Toronto.

David Dearman is a Ph.D. student at the University of Toronto. His research attempts to bridge the fields of Human-Computer Interaction, Ubiquitous Computing and Mobile Computing.

Koji Tatani is a Ph.D. student at the University of Toronto. His research interests lie in Human-Computer Interaction and ubiquitous computing with an emphasis on hardware and sensing technologies.

Khai N. Truong is an Associate Professor in the Department of Computer Science at the University of Toronto. His research interests lie in Human-Computer Interaction and Ubiquitous Computing.

Presentation Venue: This paper was presented at UIST '10 Proceedings of the 23rd annual ACM symposium on User interface software and technology in New York.


Summary: 
Hypothesis: In this paper the authors have provided a study of the human capability associated with performing foot-based interactions which involve lifting and rotation of the foot when pivoting on the toe and heel. This study is associated to controlling the mobile devices that are often located in users' pockets. The authors develop a system to learn and recognize foot gestures using a single commodity mobile phone placed in the user's pocket or in a holster on their hip. The system that they built uses acceleration data recorded by a built-in accelerometer on the mobile device and a machine learning approach to recognizing gestures.
The authors designed various gestures for the Study of Foot-Based Interaction Space:
Axis of Rotation:
- Dorsiflexion: this involved the rotation of ankle in such a way that the angle between the shin and the foot decreased

- Plantar flexion: this involved rotation of the ankle such that the above angle increased
- Heel rotation: this involved internal and external rotation of the foot and leg while pivoting the rotation on the toe of the foot


Selection Task:
The participants were asked to perform a target selection task with their dominant foot while standing.
How the hypothesis was tested: Six right-footed participants were recruited from the University of Toronto. They were asked to select targets presented on a laptop places on a table in front of them. The participants were instructed to move their foot back to the origin before they started the experiment. They were them prompted to hold down the left-click button on a wireless mouse to begin the trial. After this, a red line appeared at an angular target, and the user moved his/her foot to the target angle along the axis instructed by the system. When making a selection, no visual feedback was given in order to simulate an eyes-free interaction. 
Result: Targets closer to the origin were selected more quickly than targets at the extremity of the range of selection. The selection time for the 10° target for dorsiflexion was significantly faster than the other targets. The median selection error across all targets was 11.77° for dorsiflexion, 6.31° for plantar flexion, 8.55° for toe rotation and 8.52° for heel rotation. 


Discussion:
Effectiveness: Naive Bayes resulted in 82-92% classification accuracy for the gesture space that the authors suggested in the capabilities evaluation with the mobile device attached to the side of the user's leg. This showed that foot gestures were properly recognized by the device's integrated accelerometer. However, there are some factors that limit the accuracy of these gestures.  
Reasons for being Interesting: The best advantage of this technology is that it does not demand any visual or cognitive attention from the user during its operation. On implementing the solution suggested by the authors for the real life obstrusive interactions that can interrupt this technology, this interface can greatly enhance user experience and lower accessibility barriers for the visually impaired. For e.g. a blind person can listen to music and without having to select the song, they can select different songs using the dorsiflexion gesture.
Faults: In the second study of the paper, the placement and posture of the mobile devices were fixed in the participants' pocket, which would not always be the case in a real-world setting. Also, it is very difficult to differentiate foot gestures from other activities like walking and running. However, for each of these faults, the authors have provided a valid implementable solution.

Tuesday, September 20, 2011

Blog #9: Jogging over a Distance between Europe and Australia

Paper Title: Jogging over a Distance between Europe and Australia


Authors: Florian Mueller, Frank Vetere, Martin Gibbs, Stefan Agamanolis, Jennifer Sheridan

Author Bios: 
Florian 'Floyd' Mueller is a Fullbright Visiting Scholar at Stanford University. His research includes exertion games. Exertion games are digital games which require intense physical effort. Through his research he hopes to create engaging experiences which will facilitate social and physical health benefits and address obesity.

Frank Vetere is a Senior Lecturer in the Department of Information Systems at University of Melbourne. His research interests lie in HCI and Interactive Design.

Martin R. Gibbs is a Lecturer in the Department of Information Systems at University of Melbourne. His research interests include using a variety of interactive technologies for convivial and social purposes.

Darren Edge is a researcher in the Human-Computer Interaction group at Microsoft Research in Beijing, China. His primary research interest is how abstract analysis, user research, and design thinking can be combined to create interactive technologies that can reshape human activities for the better.

Stephan Agamanolis is currently Associate Director at the Rebecca D. Considine Research Institute at Akron Children's Hospital. When this paper was written, he was the Chief Executive and Research Director at Distance Lab, a creative research initiative for digital media technology and design innovation.

Jennifer G. Sheridan is the Co-Founder and Director of BigDog Interactive. She has a Ph.D. in Computer Science.




Presentation Venue: This paper was presented at UIST '10 Proceedings of the 23rd annual ACM symposium on User interface software and technology in New York.


Summary: Hypothesis: In this paper, the author present an investigation of how technology can enhance social exertion activities like jogging. The authors have suggested a prototype called Jogging over a Distance that consists of an integrated audio channel (delivered via the headset) in order to enable participants to communicate at any time, therefore socialize while performing exertion activities. With Jogging over a Distance, two jogging partners arrange to run at the same time. Each of the jogger wears a headset and a wireless heart rate monitor strapped around their chest. They also wear a small pouch around their waist, which contains a mini computer and a mobile phone. This mobile phone voice channel helps keep latency to a minimum.
How the hypothesis was tested: The authors decided to test their prototype by using it on participants who ran in pairs. They used a qualitative approach to gather data from the participants in their experiment. They used audio recordings from the interview data after the participants ran in pairs, where each run was between 25 and 45 minutes long. The interviews contained open-ended questions about their experience and their interactions with one another. They reported 14 runs where the participants were chosen from their personal contacts who fit their profile of a social jogger.

Result: From the interview process, the authors categorized the data into points like ommunication Integration and Effort Comprehension. They reconfirmed that Jogging over a Distance facilitated a social experience similar to that experienced in co-located jogging. The fact that different physical capabilities were dismissed automatically made the people group with fellow participants with their own capabilities, thereby increasing bonding between them. The system encouraged participants to adjust their speed based on their desire to talk. They used their headsets to locate where their partner was. Not only that, through the breathing sounds of other people, they were able to identify if the other people were ahead of them or behind them.


The Effort Comprehension was the term that referred to the ability of the system to support players in understanding their exertion investment through the use of heart rate data.


Discussion:
Effectiveness:
I believe Jogging over a Distance is a very efficient system which can be used to jog spatially with other people and still get to communicate with them. It is a very good system where the partners can communicate, as well as keep a track of how fast the other person is jogging. It is a very effective tool that can help socialize and can help make one physically fit (it is designed for people who treat jogging as a social activity)
Reasons for being Interesting: I found this technology interesting because this can be used when two people are at a distance. Instead of physically meeting up with friends at a location and then jog together, this technology can allow friends to jog at their respective places with the same level of interaction and social activity.
Faults: I really liked how this technology can provide the user with immense details about their own physical activity. However the part where it provides so much details about their partner, serves nothing more than distraction to the user.

Thursday, September 15, 2011

Blog #8: Gesture Search: A Tool for Fast Mobile Data Access

Paper Title: Gesture Search: A Tool for Fast Mobile Data Access


Author: Yang Li


Author Bio: Yang Li is a Senior Research Scientist at Google. Earlier, he was a Research Associate in Computer Science and Engineering at the University of Washington and helped find the DUB (Design:Use:Build) across the HCI community on the campus.


Presentation Venue: This paper was presented at UIST '10 Proceedings of the 23rd annual ACM symposium on User interface software and technology in New York.


Summary: Hypothesis: In this paper, the author presents Gesture Search which quickly accesses the users' mobile phone data, such as applications and contacts, by drawing gestures. This Gesture Search demonstrates a novel way for coupling gestures with standard GUI interaction for e.g. by drawing gestures on the touch screen of the cell phone. Its intention is to provide a quick and a less stressful way for users to access mobile data. 
How the hypothesis was tested: He begins the demonstration of gesture search by providing an example in his paper. He gives the example of a user wanting to call a friend whose name started with 'A'. In order to search her number, he drew the letter A in the screen, which automatically started a search processes as soon as the gesture was finished. In order to test their software, they made Gesture Search downloadable through a company's internal website and asked Android phone users in the company to test it out. The users were not given any instructions for using the Gesture Search, instead they took their surveys at the end.
Result of the Hypothesis: From the randomly selected 125 users who passed the two criteria's set by the team, they collected 5497 search sessions in which a user drew a gesture query and selected a search result. They found that 61% of the collected sessions (5497) only used a single gesture whereas 82% of them used two gestures or less.




Discussion:
Effectiveness:
I believe the Gesture Search feature is an excellent tool in order to access and even manage the data on a device quickly and efficiently. I believe that if a person would get used to the functions of the tool for tasks where it can be used most efficiently, it would be able to save a lot of time and effort of the user.
Reasons for being Interesting: I found this technology very similar to the voice recognition feature found in the cell phone or a computer. Instead of typing out your friends first letter of the first name, one can simply scribble that alphabet and it would automatically start the search from the phone book. I like how it saves every one second it would always require a user to go to the search menu of the phonebook and then locate the alphabet and then press it.
Faults: This feature, if used extensively, can take a user more time than the usual method would otherwise take. For e.g. if a user decides to draw a "C" on the device every time he/she wants to enable the camera, it would take more effort and time compared to pressing a single button on the phone whose function is to start the camera in the device. Besides, in order to draw something on the screen, one has to use both hands (holding the device with one and doing the gesture with the other). This can prove to be ineffective for some situations.

Ethnography Blog #1

Prior Perceptions:
I have chosen my Ethnography project to be based on cultures of Bartenders as seen in College Station, Texas. I have chosen to study the culture of Bartenders for I believe they are the people who converse with a variety of people from the community. Bars, cocktail lounges, and taverns are the places where we as a society go for celebration, relaxation and socialization. These establishments are where our society marks milestones of life. From people who have just turned 21 to the people who are enjoying their last day of freedom, bar is a place where people find it customary to get annihilated. In this entire scenario, not many people observe the wiser individuals who are sitting behind the bar tables, serving drink after drink to all these people. Thinking about these individuals who serve people with their drinks all the time, I found it extremely interesting to ask myself “How much does one know about that person smiling in one’s happiness and sympathizing in one’s sadness?” I realized that there is barely anybody that knows what these individuals think or like! Traditionally bartenders and restaurant employees are frowned upon in a society. They are perceived as individuals who are not capable of obtaining or maintaining a decent employment. I have never come across a friend who has ever shown me interest in a bartender (unless the bartender was a lady and she was extremely attractive). Besides, it is a profession that no one aspires to pursue when they grow up. It was this thought that instigated a sudden enthusiasm in my brain to study about these individuals who come across thousands types of people in their everyday lives, and how this affects their thinking and actions. My initial plan for this activity is to go to a bar during weekday afternoons and spend some time noticing the bartender in Northgate (College Station, Texas). I want to try and notice the likes/dislikes of the person working at the particular bar before going and approaching him/her with a conversation. I am expecting my frequent visits to a few bars at Northgate makes the bartender feel comfortable with my presence and  eventually makes him/her open  up to me for a casual conversation. I believe the comfort level is extremely important as this would be the basis of my relationship with him/her. I want to make sure that the bartender eventually considers me as a friend and opens up to me; that way I would get the opportunity to learn more about him/her. My goal from this activity is to learn and notice how the people that visit bars and the notions that take place in a bar, affect the actions, decisions and the behavior of bartenders towards others. I plan to come up with a chart that describes the profession of the people who visit the bar, and what effect do those people have on the bartenders. Also, I plan to make a list of all the bars in College Station that are easily accessible to me with my group members. This way, we can keep a track of the shifts of bartenders and thereby visit the bars at that particular time.
First Results:
For starting my Ethnography, I decided to go to O’Bannon’s bar at Northgate on a Friday afternoon. I went inside the bar and found myself an empty stool that was facing the bartender and was not too far away from him. I took my laptop out and started surfing the internet. After a few minutes I went up to the bartender and purchased a coke. I went back to my table and continued to surf the internet, occasionally sipping my drink while constantly being aware of what the bartender was doing. The first fifteen minutes or so he was busy cleaning the counters and cleaning the bottles placed on the liquor shelf. I was doing exactly what I had planned to do and it gave me what I was hoping. I got to learn about the bartender in general. He was really involved in his cleaning and was generally minding his own business. He kept himself busy with something or the other, and served another customer about fifteen to twenty minutes after I got there. The new person who entered the bar started talking to the bartender. I noticed that the bartender was nice to the person and seemed to be interested in the conversation they were having. I noticed that the bartender had many people skills and was able to easily able to start a conversation with customers. I was wondering whether this was something he did because he was genuinely interested in the conversation or just so that he could get a good tip from the customer. Him and the customer were talking about different types of Whiskey they both had tried in their lives. I surfed the internet some more and after 30 minutes I went to refill my drink. This was when I had my first conversation with him. We just talked about the heat out here, and how College Stations weather changes rapidly. After the monosyllabic conversation, he went to the other side of the bar and started arranging other drink bottles. I returned to my table and started typing notes of everything I had noticed so far. From the conversation he had with the customer, it seemed that he was very passionate about his liquor. The fact that the other person did not leave a tip to the bartender when he was finished, and seeing that the latter was not bothered by that at all, I assumed that the bartender was enjoying the conversation he was having with the customer. It is not surprising for him to have a broad knowledge about the drinks being a bartender, and I would not be surprised to learn if he was an alcoholic. However, at this point of time it is just a question for me whether he is an alcoholic or not. From the small conversation that I had with him, I found him to be a non-fussy and a content person. I noticed that he was a good employee, looking at the amount of effort he was putting in making the liquor bottles shine and keeping the bar table clean. I found this visit to my bar very interesting. I wanted to keep my first visit this was itself, because I wanted to try to make him comfortable with my presence in the bar. My plan is not to spy on him, but I want to make sure I do not make any mistakes in my behavior as that might prevent him from opening up to me.

Wednesday, September 14, 2011

Blog #7: Performance optimizations of virtual keyboards for stroke-based text entry on a touch-based tabletop

Paper Title: Performance optimizations of virtual keyboards for stroke-based text entry on a touch-based tabletop

Author: Jochen Rick


Author Bio: Jochen Rick is an Assistant Professor in the Department of Educational Technology at the Saarland University. He has pursued several research projects based on developing innovative software.

Presentation Venue: This paper was presented at UIST '10 Proceedings of the 23rd annual ACM symposium on User interface software and technology in New York.

Summary: Paper Hypothesis: In this paper, Jochen investigates the influence of keyboard layout on expert text-entry performance for stroke-based entry. Based on empirical data, he creates a model of stroking through a series of points based on Fitts' law. Fitts's law is a model of human movement in human-computer interaction that predicts that the time required to rapidly move to a target area is a function of the distance to the target and the size of the target. He then uses that model to evaluate various keyboard layouts for both, tapping and stroking input.
How the hypothesis was tested:  He conducts an empirical study in order to create a better approximation of tapping and stroking, by investigating the role of distance and angle on the different segments of a stroke sequence [see diagram]. From his study, he realized that for each stroke sequence in the series, the distance D was varied by an integer multiple of the diameter of a point W from 1 to 8. The angles α and δ were varied as multiples of 30° from  to 330°.
Hypothesis Result:  He constructed 3 plots based on the averages of the stroke times by the distance ratio and then followed Fitts' law which states, that similar actions should conform to a similar mathematical model. He created a mathematical model in terms of the variables described above for the BeginningMiddle, and the End segments of the line.

Discussion: The stroke timing model designed by Jochnen in this paper provides a useful tool for comparing the performance of different keyboard layouts for stroke-based text entry. This model can be used to evaluate an arbitrary keyboard layout, that can determine the optimum arrangement of the 26 letters for a specific layout that can enable a human to stroke all the words in the PG lexicon in less than 20 hours. I think Jochnen has done an excellent job in building up a mathematical model (with reasonable constraints) that can help humans get started in finding a keyboard layout which can increase typing speed and efficiency, thereby improving efficiency.

Monday, September 12, 2011

Blog #6: TurKit

Paper Title: TurKit: Human Computation Algorithms on Mechanical Turk

Authors: Greg Little, Lydia B. Chilton, Max Goldman, Robert C, Miller

Authors Bios:

Greg Little is a student at MIT. His personal website is glittle.org.

Lydia Chilton is a Computer Science grad student at University of Washington. She got undergraduate degrees in Economics and EECS and a Master’s degree in EECS from MIT.

Max Goldman is a graduate student at MIT CSAIL Labs. His areas of study are User Interfaces and Software Development.

Robert C. Miller is an Associate Professor in the EECS dept. at MIT. He is also the leader of the User Interface Design Group in the CSAIL Labs.

Presentation Venue: UIST '10 Proceedings of the 23nd annual ACM symposium on User interface software and technology


Summary:Paper Hypothesis: TurKit is a toolkit for prototyping and exploring algorithmic human computation. Mechanical Turk (MTurk) provides an on-demand source of human computation. This provides a tremendous opportunity to explore algorithms which incorporate human computation as a function call. 

General Summary: Amazon uses such a mechanical turk in which users are paid small amounts of money for completing the human intelligence tasks (HITS) like writing product reviews. However, various systems challenges make this difficult in practice, and most uses of MTurk post large numbers of independent tasks. TurKit provides an API written in JavaScript for accomplishing MTurk Tasks. TurKit is a toolkit for prototyping and exploring algorithmic human computation, while maintaining a straight-forward imperative programming style. The authors present the crash-and-rerun programming model that makes TurKit possible, along with a variety of applications for human computation algorithms. The authors also present case studies of TurKit used for real experiments across different fields. The crash-and-rerun model favors usability over efficiency, but does so at an inherent cost in scalability. So, one of the major limitations of this system is expensive space complexity.

Discussion:
Companies like Amazon.com, ebay, other e-commerce companies and companies that rely on customer ratings have been using mechanical turks for quite some time now. They have to stick to this procedure since these tasks require human intelligence and can not be achieved using computer algorithms. These systems have a drawback when it comes to scalability, but with modern processors and cheap storage solutions, that doesn't quite seem to be an issue.