Paper Reading #20: The aligned rank transform for nonparametric factorial analyses using only anova procedures

The Aligned Rank Transform for Nonparametric Factorial Analyses Using Only ANOVA Procedures


Authors - Jacob O. Wobbrock, Leah Findlater, Darren Gergle, and James J. Higgins


Authors Bios - Jacob O. Wobbrock is an Associate Professor at the University of Washington and has a PhD from  Carnegie Mellon University.
Leah Findlater will be an Assistant Professor at the University of Maryland next year, has taught at the University of Washington, and has a PhD from the University of British Columbia.
Darren Gergle is an Associate Professor at Northwestern University and has a PhD from Carnegie Mellon University.
James J. Higgins is a Professor of Statistics at Kansas State University and has a PhD from the University of Missouri-Columbia.


Venue -  This paper was presented at the CHI '11 Proceedings of the 2011 annual conference on Human factors in computing systems.


Summary


Hypothesis - In this paper, researchers explain that common procedures used in analyzing non-parametric data tend to be error prone and propose a new system for analyzing data. This new procedure, called the Aligned Rank Transform (ART), allows researchers in the field of HCI to accurately analyze non-parametric data without fear of error and has easy to use tools to go with it. The hypothesis is that ART is a better way to analyze data than any other method currently in use in HCI and can be very useful in real world applications.


Content - ART corrects for requirements of ANOVA statistics that may not be true in HCI research such as normality. This is done by computing residuals, computing estimated effects for interactions, computing aligned responses, assigning average ranks, performing an ANOVA on this new data, and checking for correctness by checking sums.


Methods - The ARTool and ARWeb products make using ARTs easy and accessible. The ARTool parses long-format data and produces rankings based on this data. ARTool makes only 2  assumptions for use: The first column of data is an identifier and the last is a numeric response. Everything in between is assumed to be factors for the response. ARWeb performs exactly the same as ARTool just in a web setting that is more accessible to everyone with an internet connection. 


Results - The ARTool was used in a real-world case in evaluating results of a satisfaction survey given to users of a test interface. The results were analyzed using a standard ANOVA first and then an ART to see if any observable interaction concurred in the study. The ANOVA did not detect anything and noted their was no significant interaction but the ART found significant interaction and questioned the findings found earlier which agrees with the researchers initial perception that interaction was obviously present. Other examples were also tested with the ART and were well received as rules could be broken that traditional AVOVAs required.


Conclusion - The researchers conclude by stating that ART is useful when analyzing non-parametric data and has been useful in several cases that the researchers had worked on.


Discussion


I think the researchers achieve their goal of providing a better way to provide to analyze data for HCI research. This paper is interesting because it changes something that is already established to work with HCI.

Paper Reading #19: Reflexivity in digital anthropology

Reflexivity in Digital Anthropology 


Authors - Jennifer A. Rod


Authors Bios - Jennifer A. Rod I am an Assistant Professor at Drexel's School of Information and has a PhD in Computer Science from UC Irvine.


Venue - This paper was presented at the CHI '11 Proceedings of the 2011 annual conference on Human factors in computing systems.


Summary


Hypothesis - In this paper, the researcher compares different styles of anthropology with the goal of forming a style to be coined digital anthropology that people can use reliably in the future when studies like this are needed. The hypothesis of this paper is that through examination and study digital anthropology can be created and will benefit CHI in future research.


Content - There are 3 approaches to ethnography and anthropology that can apply to HCI although only one is currently used in digital anthropology. The realist approach focuses on the process of collecting information over a long period of time and determining causes for what was observed through careful observation and experimentation without much connection to the author performing the study. The confessional approach relies on the ethnographer explaining their own involvement with the subject being studied and allows for a greater understanding of the perspective being observed. The impressionistic approach focuses on telling a story and letting detailed observation speak for itself in setting the stage for the ethnography and allowing for future analysis. 


Methods - The 3 approaches to ethnography mentioned above each bring some unique new aspects to the field of digital anthropology. Discussing rapport, the relationship between the observer and subjects being studied, allows for readers to have a better understanding of how data was collected which is crucial when acting on ethnographic results. Participant observation is important in ethnography because it gives us an experiential account of the subject being studied and gives more voice to the author. The use of theory in ethnography is very fundamental considering that it is usually on this level that any advancements are made from ethnography and theory allows for quicker immersion of the author into the setting they are studying. 


Results - There are 3 specific forms of ethnography that can applied to HCI developed from the information above. Formative ethnographies study current use of a product or tool and make observations as to how it can be improved. Summative ethnographies focus purely on how a digital tool is used by a specific group of people and explain this relationship in depth with no suggestions for improvement allowing these studies to be untainted by goals but not providing too much usefulness to the field of HCI. Iteratively evaluative ethnographies are studies that are conducted by putting a prototype product or tool in use and studying how it becomes used by participating in its use and observing others allowing for more iterations to be created and evaluated all over again until a compelling and complete product has been created.


Conclusion - The researcher concludes the paper by stating that standards need to be adopted for ethnography in HCI in order to continue improving on technology and its relationship with users. The results from this paper help to explore some specific areas where HCI can get these standards from and allow for a more reflexive approach to digital anthropology than what is currently being used preserving the author's voice in these studies which is crucial when moving forward with technological advancements.


Discussion


I think the researcher partially succeeds in developing digital anthropology practices  that can result in better HCI research in the future because although many suggestions are made in the paper most of them are just regurgitation of facts from other sources just applying them a little more towards HCI than they have in the past. I did find the paper mildly interesting as I do think that HCI needs a better way to evaluate interaction with technology instead of just producing "better" offerings in theory only to frustrate and fail.

Paper Reading #18: Biofeedback game design: using direct and indirect physiological control to enhance game interaction

Biofeedback game design: using direct physiological control to enhance game interaction

Authors - Lennart E. Nacke, Michael Kalyn, Calvin Lough, and Regan L. Mandryk

Authors Bios - Lennart E. Nacke was a postdoctoral associate researcher at the University of Saskatchewan at the time of this paper's publication.

Michael Kalyn is a student researcher at the University of Saskatchewan and holds a degree in Computer Engineering.

Calvin Lough is also a researcher working under Dr. Mandryk in the Interaction Lab at the University of Saskatchewan.

Regan L. Mandryk is an Assistant Professor at the University of Saskatchewan and has a PhD from Simon Fraser University.

Venue - This paper was presented at the CHI '11 Proceedings of the 2011 annual conference on Human factors in computing systems.

Summary

Hypothesis - In this paper, researchers explore the use of physiological input in video games and attempt to find a place for them in the modern industry. The hypothesis is that physiological input has a place in modern gaming and this paper will find where that place is.

Content - The researchers built a 2D side scrolling using the Mircrosoft XNA framework and XBOX 360 control mappings to test their hypothesis. The game consisted of many features that were controlled by physiological input in addition to the standard XBOX controller. They also built a library that received and processed sensor data before sending it to the game.

The physiological controls are:

• GAZE - Eye tracking

EMG - Muscle sensor

GSR - Sweat detection

EKG - Heart Rate sensor

RESP - Breathing rate sensor

TEMP - Temperature sensor (require blowing on)

Methods - To evaluate the plausibility of direct and indirect physiological control, 10 participants were asked to play through 3 test conditions. 1 of the conditions was a control and therefore had no physiological control. The other 2 conditions added 2 indirect and 2 direct methods of physiological control to the game in addition to the GAZE system and standard XBOX controller that were present in both. The participants played through the 3 conditions in random order, for about 10 minutes on each condition, and then filled out a survey concerning their experience with the physiological control.

Results - The first variable analyzed was how fun users found the conditions to be. The participants found the conditions with the physiological control to be significantly more fun than the control condition but their was no difference between the 2 physiological control conditions. Users responded by saying the physiological controls helped to immerse them into the game and were intuitive. Participants also found the physiological control to be very novel and noted that there was a learning curve but it rewards those that learn. The participants greatly preferred the GAZE and RESP sensors to all of the others. Users easily chose direct controls over indirect controls and responded accordingly when asked for opinions on the GSR and EKG sensors noting that neither of them felt controllable. 

Conclusion - The researchers conclude by saying that physiological input is feasible to implement in games and when used in the direct control format can be very popular and immerrsive however, indirect control does not have a foreseeable future as a mechanic control but maybe can be used to control environmental variables like background color and activity similar to a mood ring. 

Discussion


I think the researchers prove their goal of establishing physiological input as a viable means for control in video games. I think research has a long way to go in establishing this as a real product though. The controllers that we currently have exist because they can be mass produced and used for many different tasks. Physiological input sensors are not intuitive to set up and have no precedent in the market. The only way, sensors like this stand a chance is if they are shipped with consoles directly as opposed to add-ons that can be bought later.

Paper Reading #17: Privacy risks emerging from the adoption of innocuous wearable sensors in the mobile environment

Privacy Risks Emerging from the Adoption of Innocuous Wearable Sensors in the Mobile Environment


Authors - Andrew Raij, Animikh Ghosh, Santosh Kumar, and Mani Srivastava


Authors Bios - Andrew Raij is a Post Doctoral Fellow in the Wireless Sensors and Mobile Ad Hoc Networks Lab (WiSe MANet) at the University of Memphis and has a PhD from the University of Florida.
Animikh Ghosh is a Junior Research Associate at Infosys Technologies Ltd. and has a Masters of Computer Science from the University of Memphis.
Santosh Kumar is an Associate Professor at the University of Memphis and advises the WiSeMANet Lab.
Mani Srivastava is a Professor of Computer Science at UCLA and is also highly involved as an electrical engineer.


Venue - This paper was presented at the CHI '11 Proceedings of the 2011 annual conference on Human factors in computing systems.


Summary


Hypothesis - In this paper, researchers point out that mobile sensors used in the study of one's health may also be used in conjunction with machine learning algorithms, or just basic reasoning skills, to reveal private information that one does not wish to be known such as smoking or drinking habits. The study proposed by the researchers will evaluate how much individuals care about their private habits being made public. The hypothesis is that people do not want certain personal attributes, such as habits or health conditions, exposed in a way that other people can decode and potentially use against them, i.e. seemingly innocuous physiological data.


Content - The researchers developed a framework to better explain the scenarios being discussed in the paper and it consisted of measurements, behaviors, contexts, restrictions, abstractions, and privacy threats. Measurements are raw data that comes from sensors such as acclerometer readings and heart rates. Behaviors are actions the user performed that can be inferred from the measurements such as seizures. Contexts explain behaviors by observing the environment that the behavior occurred in such as time, place, and people that were nearby. Restrictions can be applied to all 3 of the previous elements and produce a limiting effect such as limiting access to accelerometer data or keeping the time private. Abstractions offer a way to restrict data to a desirable amount so as to have enough data to monitor whatever is being studied but leaving out other details. Privacy threats are harms that result from matching data to an identity.

methods for the 2 groups

Methods - The study had 3 goals: assess privacy concern of individuals before and after the study (when their data was at stake), use the framework to examine restrictions and abstractions, and assess how identification of the data affects the concern levels of participants. 66 participants were recruited for the study and divided into 2 groups. 1 group, Group NS, only filled out a privacy survey and the other, Group S, gave physiological, behavioral, and psychological data to a sensing device, the AutoSense, for 3 days with questionnaires throughout the study. Upon completion of the data collection participants viewed the data collected in a system called Aha visualization, developed for this study, that showed the data at different abstraction levels and responded to a privacy questionnaire knowing what was collected. 


Results - Privacy concerns between Groups NS and S before the study were minimal but Group S after the study had significantly higher concerns and did not like the idea of someone having access to that data. The impact restrictions and abstractions had on the concerns showed what data is most sensitive when grouped with other data. For example, the highest concern level was shown when physical and temporal data was available making the times and locations of the user visible. Adding timestamps in general always increased concern. Participants also showed higher levels of concern when asked how they felt regarding releasing the data linked by identity to the general public compared to releasing the data anonymously.


Conclusion - The researchers conclude by saying they can conclude 3 things from this study: people don't properly analyze the risk of releasing data unless they have a stake in it, concern raises when physical and temporal data is connected together but can be reduced through restriction and abstraction, and people are willing to share their data (identifying or not) with researchers but not the general public.


Discussion


I think the researchers proved their hypothesis that people do not want certain information regarding tracking exposed to the public but interestingly only when they have a stake in the data being released. This study can be used by developers in the future in determining what data to keep sensitive and more importantly what to tell users so that they know exactly what is being recorded before consenting to anything.

Paper Reading #16: Classroom-based assistive technology: collective use of interactive visual schedules by students with autism

Classroom-Based Assistive Technology: Collective Use of Interactive Visual Schedules by Students with Autism


Authors - Meg Cramer, Sen H. Hirano, Monica Tentori, Michael T. Yeganyan & Gillian R. Hayes


Authors Bios - Meg Cramer, Sen H. Hirano, and Michael T. Yeganyan are students in the Department of Informatics at the University of California.
Monica Tentori is a student in the School of Computer Science at the Universidad Autónoma de Baja California.
Gillian R. Hayes is an assistant professor at UC Irvine and has a PhD from the Georgia Institute   of Technology.


Venue - This paper was presented at the CHI '11 Proceedings of the 2011 annual conference on Human factors in computing systems.


Summary


Hypothesis - In this paper, the researchers make reference to vSked which is an interactive and collaborative assistive technology for visual schedules created primarily as a way to assist teachers of autistic children. The hypothesis being tested in this paper is that vSked, when implemented in a classroom setting, can help students with autism be more independent and positively respond to community building activities.


Content - vSked is an interactive and collaborative assistive technology that replicates the functionality of visual schedules, choice boards, and token-based rewards in an integrated system. The system consists of a central touch screen display and an ultramobile PC 
(UMPC), a  touch screen handheld device, for each child connected to said device wirelessly. The teacher controls activities and schedules of students with the large, central touch screen. Each student's device allows for three kinds of interaction: multiple choice questions, voting, and alerts. Appropriate feedback is given based on the nature of the question and the students' answer.


Methods - The study conducted in this paper consisted of 3 deployments of vSked to classroom environments. During each study, teachers and aides were interviewed in both group and individual manners on a regular basis. Special video interviews were also conducted on a less frequent basis and were scored based on a set of criteria determined by the researchers to be important. Participants in this study included 2 teachers, 8 teacher assistants, and 14 students devided between 2 classrooms. To analyze the effectiveness of vSked, the researchers performed a quantitative analysis of certain variables (amount of work to transition, prompt students, etc.) before the implementation of vSked and after the use of vSked. An ANOVA was used to compare the before and after results of the survey and decide on the effectiveness of the system. All notes and interviews were also taken into consideration when making the final analysis.


Results - The first variable analyzed by the researchers was that of independence and the need for teachers to prompt students for an answer and further prompting for a right answer if incorrectly chosen at first. vSked resulted in a 54% decrease in prompting from teachers and a large drop in prompting from aids, although not enough to be statistically significant. The feedback from the device proved to be very valuable as many students responded positively when the fireworks display appeared after answering correctly. Also, the shaking of the correct answer after a student selected incorrectly was effective in getting students select the right answer. Consistency and predictably was the next variable analyzed and is important because scheduling allows a student to see what is happening today and prepare for it reducing surprises or anything that may upset a student. Also electronic scheduling makes transitioning faster as teachers can move everybody through the schedule with the touch screen. Transition time was lowered 61% using vSked which helps prevent students from down time in between activities which can trigger an undesirable reaction. When the students were to be rewarded tokens for their acheivments during the day, the teachers could use vSked to provide instant gratification to both parties through a fireworks display that stimulated many students at a time. Interacting with the community is very important when instructing students with autism and vSked helped in this are as well introducing new behaviors for the teachers to practice. First, students seemed to take an active interest in what their friends were doing and second, teachers began presenting the final token before rewards to students in front of the whole class to better involve all students in the rewarding process and encouraging others to do the same.


Conclusion - The researchers conclude by stating that although similar assistive technologies exist for special education class, very few attempt to unite individual and group accomplishments like vSked. They also suggest that this study has shown that technologies like vSked can help to alleviate high student-to-teacher ratios by prompting and rewarding students on the device itself.


Discussion


 I think the researchers proved the plausibility that their system helps with key areas in special education but they failed to provide any real data on the topic and further studies will be needed to develop said data. This study will hopefully make future studies possible for this reason. I think unifying individual and group activities through technology is a powerful tool that teachers will be able to use to a much higher degree in the future. 

Paper Reading #15: Madgets

Madgets: Actuating Widgets on Interactive Tabletops


Authors - Malte Weiss, Florian Schwarz, Simon Jakubowski, and Jan Borchers


Authors Bios - Malte Weiss is a PhD student and research assistant at the Media Computing Group of RWTH Aachen University specializing in interactive surfaces.
Florian Schwarz is a Diploma Thesis Student at RWTH Aachen University and is interested in translucent controls on interactive tabletops.
Simon Jakubowski is a student assistant at RWTH Aachen University and is supervised by Malte Weiss.

Jan Borchers is a professor at RWTH Aachen University and leads the Media Computing Group in researching human computer interaction.


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


Summary


Hypothesis - In this paper, researchers introduce magnetic widgets, or Madgets, which let interactive tabletops give and receive information from widgets placed on their surface. Madgets are easy to build, flexible, inexpensive, and do not require any builtin electronics or power source. The hypothesis is that Madgets enables new interaction with complex actuated tabletop tangibles and will prove valuable as research in this field continues.


Methods - The researchers implemented Madgets using custom hardware, actuation algorithms, tracking algorithms, and ideas concerning what needed to be supported by the project.

Results - The surface used for Madgets was built by the researchers using a TFT panel from a Samsung TV, a sheet of EL foil, 228 electromagnets, fiber optic cables, LEDs, and 3 cameras. The surface utilized Diffused Surface Illumination (DSI) for touch recognition. The widgets are built using clear acrylic parts and magnets to both hold it in place and perform tasks. The actuation algorithms control the magnets when they are moving widgets, tangential actuation, or performing tasks with widgets, normal actuation and they also keep the magnets relatively cool by cycling magnets for other magnets. The tracking algorithms calculate input on the surface by using gradient markers on the IR results returned to the cameras. Widget and finger inputs are detected in this manner and pattern matching is used in determining which widget is present before mapping the location to internal coordinates. 


Content - Madgets allow for persistence (GUI interaction), remote calibration (group control), and ad-hoc use (moving a Madget closer to a user by touch). Height is an important aspect to Madgets and allows for buttons to move up and down. Resistance and vibrations are 2 possible types of feedback that Madgets can deliver to users indicating a completed action or an exceeded limit.


Conclusion - The researchers conclude by saying Madgets provides low-cost widgets and new actuation dimensions allowing for more research to continue in prototyping more widgets easily and working on better aestethics for the system as a whole as well as finding more appropriate feedback that coincides with the goals of Madgets.


Discussions


I think the researchers achieved their goal of expanding actuation interaction but I remain unconvinced of the need for such a device. They gave good examples for widgets but they did not expand upon what they could be used for or how they could possibly work together as I imagine they would in a real-world setting. Future work will be needed in figuring out applications for this system. I think the way in which the hardware was built was interesting using many different components in innovative ways and combining that with new algorithms to track and interpret data given the unusual hardware.

Paper Reading #14: TeslaTouch

TeslaTouch: Electrovibration for Touch Surfaces


Authors - Olivier Bau, Ivan Poupyrev, Ali Israr, and Chris Harrison


Authors Bios - Olivier Bau is a researcher at Disney Research and received his PhD from INRIA Saclay.
Ivan Poupyrev has a PhD from Hiroshima University and currently works in interactive technologies at Disney Research.
Ali Israr has a PhD in mechanical engineering from Purdue University and specializes in haptics.
Chris Harrison is PhD student at Carnegie Mellon University and is a Microsoft Research PhD Fellow.


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


Summary


Hypothesis - In this paper, the researchers note that current touch surfaces do not give users any kind of haptic feedback resulting in drops in efficiency when used. The researchers propose using electrovibration in conjunction with touch surfaces to create a new kind of interface capable of many different haptic interactions with users. The hypothesis is that this new interface, TeslaTouch, will lead to new feedback possibilities resulting in more efficient interactions with users and be easily added to existing hardware.


Content - TeslaTouch was implemented using diffusing illumination for touch recognition on a 3M Microtouch panel originally designed for capacitive touch. Current is applied to the panel by a standard sound card controlled by the Pure Data sound programming environment. Due to the interaction users will have with different voltages, the researchers note many of the safety procedures followed in designing the device such as the fact that electrovibration does not actually pass current through a user's body and a user is exposed to the same current given off by conventional capacitive touch surfaces.The researchers explain that their implementation approach is scalable and can be applied to almost any surface as electrodes can be clear and applied easily everywhere. When compared to mechanical means of feedback electrovibration has some noticeable advantages. Some advantages electrovibration has include being more salable for large interfaces, producing no noise when active, and being more reliable than physical parts. Simulations, like writing or painting, and rubbing interactions, for picture editing, are just some of the many applications electrovibration.


Methods - Studies were conducted to observe what users perceive when touching the TeslaTouch surface to validate its use as an effective form of feedback:
1) 10 participants were asked to touch the TeslaTouch in 4 different configurations and give their feedback reagarding their experiences. This study will help the researchers decide what settings to adjust to achieve certain textures.
2) The absolute detection thresholds were determined by 10 participants touching a screen split into 2 sections and determining which had a tactile stimulus. The stimulus would be randomly chosen from 5 frequencies and the participants' choices decided how much the intensity, dB, would change. If a user chose right the intensity decreased and vica versa if a user chose wrong but after so many trials the scale of the change decreased so as to narrow down the threshold.
3) The frequency and amplitude discrimination thresholds were calculated by 7 participants choosing the unique surface from a set of 3 that had a test stimuli and 2 identical reference stimuli with intensity of 15 dB higher than the absolute detection threshold.


Results - The results of the methods mentioned above will help with determining what bounds to use and what factors affect the feeling:
1) The low frequency settings were viewed as being rougher than the high frequency settings. Amplitude changes in the high frequency settings changed how smooth or "waxy" the surface the felt while amplitude changes in the low frequency settings affected the perceived stickiness the surface possessed. 
2) The absolute detection thresholds were found to be severely affected by the frequency levels although a reliable figure was found to use in the following tests.
3) While the discrimination threshold was kept constant, frequency was found to severely affect user perception with the lower frequencies resulting in far more JNDs than the higher frequencies. Amplitude was found to be independent of frequency resulting in clear results.


Conclusion - The researchers conclude by stating that they have shown that electrovibration is a viable option for touch feedback in the future and that the abstract nature of the technology will allow for many applications to be uniquely implemented with it.


Discussion


I think the researchers successfully proved their hypothesis that electrovibration is a viable form of feedback for touch interfaces. The most interesting part of this research to me is the abstract nature of the tool which, unlike physical vibration which can only be vibrated at different intensities, has the potential to be used in many different ways such as simulating stick surfaces as opposed to bumpy surfaces or waxy surfaces. I think this technology has a future in the mobile tablet industry if more research is put into it and people start using it as the appeal for a device that supports this would be very high among the public in my opinion.