The author discusses the issue of ethnography-overuse. Many people are using ethnographies in their studies and aren't adhering to the traditional methods of doing them. They explain that doing things these ways could be more detrimental than they are beneficial.
Additionally, blindly following the results could lead to bad design. Instead, additional factors should be considered in order to determine what the best design for a given problem is. I thought this paper was a pretty tough read. It came across as more of a rant than anything.
Tuesday, May 12, 2009
Human-Centered Design Considered Harmful
I think it was what I expected to read. He seemed to back-track yet again. Now, he talks about how design should follow a more activity-centered philosophy instead of being human-centered. Human-centered design leads to very complex systems. Every suggestion is taken into account and the final product is continually modified and expanded until it is a giant mess. With activity-centered design, suggestions are evaluated in terms of the requirements of the activity. He explains, "The best way to satisfy users is sometimes to ignore them."
Design this way requires developers that know exactly what activity they are designing a product for. When developing, they should maintain an "I know what's best for you" attitude. Human-design ensures that the products work and they are usable by those that they are meant for. Following an activity-centered approach can lead to great design. This is where the innovative products come from. A clear concept of the end-product is kept in mind, and things that contradict it are thrown aside.
Design this way requires developers that know exactly what activity they are designing a product for. When developing, they should maintain an "I know what's best for you" attitude. Human-design ensures that the products work and they are usable by those that they are meant for. Following an activity-centered approach can lead to great design. This is where the innovative products come from. A clear concept of the end-product is kept in mind, and things that contradict it are thrown aside.
Usability Evaluation Considered Harmful
Main message- "The choice of evaluation methodology – if any – must arise from and be appropriate for the actual problem or research question under consideration."
They explain that researchers should first sit down and look over what they are trying to demonstrate in their experiment. Then, the method that best demonstrates this concept should be used. Some of these methods include usability studies, design critiques, design alternatives, case studies, cultural probes, reflection, design rationale, etc. They go on to explain that a combination of these methods is even more useful to prove your point.
I doubt this is just me... but this is completely obvious. I would like the 20 minutes of my life that I spent reading these 10 pages back please.
They explain that researchers should first sit down and look over what they are trying to demonstrate in their experiment. Then, the method that best demonstrates this concept should be used. Some of these methods include usability studies, design critiques, design alternatives, case studies, cultural probes, reflection, design rationale, etc. They go on to explain that a combination of these methods is even more useful to prove your point.
I doubt this is just me... but this is completely obvious. I would like the 20 minutes of my life that I spent reading these 10 pages back please.
Fitts' Law
Equation:
Basically, the law predicts the time required to point to a specific area using any type of pointing device. Proposed in 1954, the idea has withstood the rigorous test of time. Additionally, it is able to be applied over a wide range of devices. It first applied to very simple pointing devices that were used in the 50's. Today, the same ideas still hold true to stylus devices on multi-touch screens. Unfortunately, there are many interfaces that are designed which completely ignore Fitt's Law.
Basically, the law predicts the time required to point to a specific area using any type of pointing device. Proposed in 1954, the idea has withstood the rigorous test of time. Additionally, it is able to be applied over a wide range of devices. It first applied to very simple pointing devices that were used in the 50's. Today, the same ideas still hold true to stylus devices on multi-touch screens. Unfortunately, there are many interfaces that are designed which completely ignore Fitt's Law.
Wednesday, April 29, 2009
Paper from CHI 2009
Comments:
Comment #1
Comment #2
Comment #3
Focus on Driving: How Cognitive Constraints Shape
the Adaptation of Strategy when Dialing while Driving
Duncan P. Brumby, Dario D. Salvucci, Andrew Howes
Link to CHI 2009 paper.
Overview:
As mobile devices become more common, more distracted drivers take to the roads. Over the years, studies have concluded that interacting with other people or devices while driving increases the risk of being involved in an accident. This results from the driver's need to perform multiple tasks at once--diverting their attention off of the road. These tasks must be interleaved together in order to accomplish them. This paper focuses on identifying the different methods people use to interleave concurrent tasks.
Experiment:
The experiment was conducted using a driving simulator. Subjects drove a vehicle down the center lane of the highway which was lined with construction cones on either side. The vehicle moved at a constant speed so the subjects only had to focus on keeping the vehicle in the center lane and dialing numbers on a cell phone. Key presses on the phone were recorded and timestamped.
In the first part of the experiment, participants were timed on how fast and accurately they could dial the number. Then, they interacted with the simulator, trying to keep the vehicle centered in the lane while traveling at a constant speed. In the second part of the experiment, subjects interleaved the tasks based on different priorities: dialing focus or steering focus.
Results:
The data shows that when the subjects used their phones, their performance was impaired because their attention was focused on things other than driving. Improvements in lane keeping only occurred during long delays between key presses, and the vehicle moved further away from the lane center during shorter key press intervals. The duration of time between key presses can be used to determine when drivers were focusing their attention on the driving task.
They also saw that participants use hierarchical chunks to determine when they were to switch from one task to another (ex: xxx-xxx-xxxx). The experiment shows that they would break the dialing up into these chunks and lane keeping would improve during the period of time between these chunks.
From here, they tried to determine which strategy of task interleaving would be most efficient in terms of driver performance. For this, they used a Cognitive Constraint Modeling (CCM) framework to explore alternate task interleaving strategies. They were able to derive performance predictions for each strategy that was implemented.
They found that drivers who didn't return their attention to the driving task at least twice experienced large lane deviation. Those who made a correction to steering after dialing the first chunk experienced less lane deviation while dialing the second chunk. Though it might have not been needed the first time, it decreased the amount of lane deviation they experienced in the future.
Conclusion:
Their findings support the idea that the total time a driver is distracted from their primary task is less important than the extent to which they glance back at the road while trying to complete the secondary task. Designing mobile devices that don't require long periods of interaction could be helpful in reducing the "deleterious effects of distraction."
Comment #1
Comment #2
Comment #3
Focus on Driving: How Cognitive Constraints Shape
the Adaptation of Strategy when Dialing while Driving
Duncan P. Brumby, Dario D. Salvucci, Andrew Howes
Link to CHI 2009 paper.
Overview:
As mobile devices become more common, more distracted drivers take to the roads. Over the years, studies have concluded that interacting with other people or devices while driving increases the risk of being involved in an accident. This results from the driver's need to perform multiple tasks at once--diverting their attention off of the road. These tasks must be interleaved together in order to accomplish them. This paper focuses on identifying the different methods people use to interleave concurrent tasks.
Experiment:
The experiment was conducted using a driving simulator. Subjects drove a vehicle down the center lane of the highway which was lined with construction cones on either side. The vehicle moved at a constant speed so the subjects only had to focus on keeping the vehicle in the center lane and dialing numbers on a cell phone. Key presses on the phone were recorded and timestamped.
In the first part of the experiment, participants were timed on how fast and accurately they could dial the number. Then, they interacted with the simulator, trying to keep the vehicle centered in the lane while traveling at a constant speed. In the second part of the experiment, subjects interleaved the tasks based on different priorities: dialing focus or steering focus.
Results:
The data shows that when the subjects used their phones, their performance was impaired because their attention was focused on things other than driving. Improvements in lane keeping only occurred during long delays between key presses, and the vehicle moved further away from the lane center during shorter key press intervals. The duration of time between key presses can be used to determine when drivers were focusing their attention on the driving task.They also saw that participants use hierarchical chunks to determine when they were to switch from one task to another (ex: xxx-xxx-xxxx). The experiment shows that they would break the dialing up into these chunks and lane keeping would improve during the period of time between these chunks.
From here, they tried to determine which strategy of task interleaving would be most efficient in terms of driver performance. For this, they used a Cognitive Constraint Modeling (CCM) framework to explore alternate task interleaving strategies. They were able to derive performance predictions for each strategy that was implemented.They found that drivers who didn't return their attention to the driving task at least twice experienced large lane deviation. Those who made a correction to steering after dialing the first chunk experienced less lane deviation while dialing the second chunk. Though it might have not been needed the first time, it decreased the amount of lane deviation they experienced in the future.
Conclusion:
Their findings support the idea that the total time a driver is distracted from their primary task is less important than the extent to which they glance back at the road while trying to complete the secondary task. Designing mobile devices that don't require long periods of interaction could be helpful in reducing the "deleterious effects of distraction."
Tuesday, March 24, 2009
Paper from UIST 2007
Comments:
Comment #1
Comment #2
Comment #3
LucidTouch: A See-Through Mobile Device
Daniel Wigdor, Clifton Forlines, Patrick Baudisch, John Barnwell, Chia Shen
Link to UIST 2007 paper and video.
Overview:
A potential drawback of touchscreen devices (on mobile phones) is that the user's fingers may obstruct his/her view of the screen or item they are selecting. This paper discusses a device (LucidTouch) that allows the user to control the application by touching the back of the device. This is done by overlaying an image of the user's hands onto the screen, making it appear that the device is semi-transparent. This allows users to easily select things on the screen that could otherwise potentially be obscured by their fingers or hands.
Device:
It combines a multi-touch input surface with a semi-transparent display that overlays an image of the user's hands onto the screen (illuminated semi-transparent bi-directional diffuser layer). It makes use of a camera mounted on the back of the device to capture video of the user's fingers and hands. Since there are eight possible contact points, something was needed to help users distinguish between fingers on the display. The LucidTouch makes use of red dots (hovering fingers) and blue dots (in contact with device).
Experiment Features:
The traditional QWERTY layout was used. Additionally, a modified version was also used that split the keyboard in half and reoriented it so that the user could maintain the usual "home row" while holding the device. While it might benefit touch typists, it could potentially be confusing for users who are unable to do this (look at keys when typing on a regular computer keyboard).
Since one finger can't span the entire screen space, coordinated actions between hands may be required (handing-off items from one to the other). LucidTouch expands small items as they get closer to the center of the screen to support easier hand-off between fingers.
Traversing a map was made easier by allowing it to take advantage of the multi-touch interface. The map-browsing application supported rotation, translation, and scaling, while remaining under the user’s fingers.
Experiment:
Map Browsing- users were presented a map of Cambridge, Massachusetts and asked to find the location of the lab that they were in. The task was presented four times: 1) Use only one thumb on the front of the device. 2) Use a thumb on the front and a finger on the back. 3) Make use of all fingers on the back of the device. 4) Overlaying image of the hands were removed and only the touch-cursors could be seen.
Text Entry- users were asked to type their name using both of the keyboard layouts. Each layout was used twice. First, they only used their thumbs on the front of the device. Then, they were allowed to use fingers on the back. When entering on the back of the device, first the semi-transparent image of the hands was used, and then it was removed.
Drag & Dock- users were asked to select an item and drag it to a specified location on the screen. They followed the same conditions used during the text entry part of the experiment.
Results:
For most tasks (all except for non-inverted QWERTY keyboard), participants found that using the multi-touch interface on the back was useful in accomplishing their tasks. Most users found that the semi-transparent overlay was useful. Without it, they found it difficult to determine which touch-cursor corresponded with which finger. They found that it would be useful to vary the pseudo-transparency, in order to minimize its intrusiveness.
Comment #1
Comment #2
Comment #3
LucidTouch: A See-Through Mobile Device
Daniel Wigdor, Clifton Forlines, Patrick Baudisch, John Barnwell, Chia Shen
Link to UIST 2007 paper and video.
Overview:
A potential drawback of touchscreen devices (on mobile phones) is that the user's fingers may obstruct his/her view of the screen or item they are selecting. This paper discusses a device (LucidTouch) that allows the user to control the application by touching the back of the device. This is done by overlaying an image of the user's hands onto the screen, making it appear that the device is semi-transparent. This allows users to easily select things on the screen that could otherwise potentially be obscured by their fingers or hands.
Device:
It combines a multi-touch input surface with a semi-transparent display that overlays an image of the user's hands onto the screen (illuminated semi-transparent bi-directional diffuser layer). It makes use of a camera mounted on the back of the device to capture video of the user's fingers and hands. Since there are eight possible contact points, something was needed to help users distinguish between fingers on the display. The LucidTouch makes use of red dots (hovering fingers) and blue dots (in contact with device).
Experiment Features:
The traditional QWERTY layout was used. Additionally, a modified version was also used that split the keyboard in half and reoriented it so that the user could maintain the usual "home row" while holding the device. While it might benefit touch typists, it could potentially be confusing for users who are unable to do this (look at keys when typing on a regular computer keyboard).
Since one finger can't span the entire screen space, coordinated actions between hands may be required (handing-off items from one to the other). LucidTouch expands small items as they get closer to the center of the screen to support easier hand-off between fingers.
Traversing a map was made easier by allowing it to take advantage of the multi-touch interface. The map-browsing application supported rotation, translation, and scaling, while remaining under the user’s fingers.
Experiment:
Map Browsing- users were presented a map of Cambridge, Massachusetts and asked to find the location of the lab that they were in. The task was presented four times: 1) Use only one thumb on the front of the device. 2) Use a thumb on the front and a finger on the back. 3) Make use of all fingers on the back of the device. 4) Overlaying image of the hands were removed and only the touch-cursors could be seen.
Text Entry- users were asked to type their name using both of the keyboard layouts. Each layout was used twice. First, they only used their thumbs on the front of the device. Then, they were allowed to use fingers on the back. When entering on the back of the device, first the semi-transparent image of the hands was used, and then it was removed.
Drag & Dock- users were asked to select an item and drag it to a specified location on the screen. They followed the same conditions used during the text entry part of the experiment.
Results:
For most tasks (all except for non-inverted QWERTY keyboard), participants found that using the multi-touch interface on the back was useful in accomplishing their tasks. Most users found that the semi-transparent overlay was useful. Without it, they found it difficult to determine which touch-cursor corresponded with which finger. They found that it would be useful to vary the pseudo-transparency, in order to minimize its intrusiveness.
Paper from CHI 2008
Comments:
Comment #1
Comment #2
Comment #3
Electronic Voting Machines versus Traditional Methods:
Improved Preference, Similar Performance
Sarah Everett, Kristen Greene, Michael Byrne, Dan Wallach,
Kyle Derr, Daniel Sandler, Ted Torous
Link to CHI 2008 paper.
Overview:
An estimated 66 million U.S. citizens submitted their vote in the 2006 Presidential Election using a direct recording electronic (DRE) system. Though they are widely used, little research has been done to prove they are more usable than more traditional methods of voting. This paper compares usability data from a DRE with that of other methods (level machines, punch cards, paper ballots).
Experiment 1:
The first experiment presented the usual DRE voting system. Subjects were presented first with an instruction screen. After that, they were able to vote on each item/proposition in the ballot. Navigating through each page was done using a "Next Page" and "Previous Page" button. After all items had been voted on, all of their selections were summarized on a screen so users could double-check their choices. From there, the ballot could be submitted. After submitting their votes, participants completed a survey (System Usability Scale, measuring satisfaction). The first experiment composed of two separate parts.
Experiment 1A:
In this experiment, the subjects were divided into two groups. The first group was instructed to vote whichever way that they wanted. The second group was given a piece of paper that instructed them how to vote on each issue. Each participant voted using the DRE and an additional method (lever machine, paper ballot, punch card).
Undirected, Directed with no roll-off.
Experiment 1B:
This experiment was similar to the previous, except for one aspect. The subjects were divided into three groups, instead of two. The third group was also given a piece of paper that instructed them how to vote on each issue, but on some issues they were told to not vote.
Undirected, Directed with no roll-off, Directed with moderate roll-off.
Results:
There wasn't a large distinction among the average voting times between the DRE and other methods. The only distinct improvement was with the lever machine. Also, people with more computer-experience took less time to vote on the DRE than other participants with less experience. Based on the results of the SUS, they found that participants preferred using the DRE to all other voting methods, regardless of any individual characteristics (age, computer-experience, etc). They also found that the DRE didn't reduce the number of voting errors that occurred. In conclusion, they found that changing the voting technology didn't result in less voting errors.
Experiment 2:
Voters rarely choose to vote on every issue that they are presented with on a ballot. The further they go down the ballot, the less likely it is that a voter will vote in a given race. Experiment 2 focused on comparing the traditional "sequential" voting design with a system where users could start on an overview page and jump to the individual elections that they wanted to vote on. Though it obviously would reduce the time users spent voting, would it also affect usability or increase voting errors?
Again, participants were divided into two groups. The first group voted using the "sequential" voting system. The second group used the new webpage-like system. The same information-conditions were used: undirected, directed with no roll-off, directed with moderate roll-off. In addition, a fourth condition was added--directed with additional roll-off. In this experiement, all participants voted three times: first using the DRE, then using one of the three traditional methods, then again with the same type of DRE. This time, no surveys were given after voting.
Results:
Of course, they found that the average completion time for the direct DRE (269.9s) was lower than that of the sequential DRE (442.3s); however, no reliable differences were found between the direct DRE and the other traditional voting methods. No differences were determined in any of the three directed information conditions. For the undirected condition, they found that the sequential voting method (910s) was much slower than the direct voting method (205s). This is because participants that used the direct DRE system voted in far fewer races than those using the sequential DRE.
They also found that voting errors occurred more often on the direct DRE than on the sequential DRE. This is due to the fact that almost 25% of participants using the direct DRE prematurely submitted their ballots before they intended. Regardless of the voting method used, over 34% of all ballots that were cast contained at least one error.
Though the direct DRE was much faster than the sequential DRE, the subjective usability ratings for the sequential system were higher. This was attributed to the fact that the direct DRE systems were inaccurate and resulted in more voting errors.
Comment #1
Comment #2
Comment #3
Electronic Voting Machines versus Traditional Methods:
Improved Preference, Similar Performance
Sarah Everett, Kristen Greene, Michael Byrne, Dan Wallach,
Kyle Derr, Daniel Sandler, Ted Torous
Link to CHI 2008 paper.
Overview:
An estimated 66 million U.S. citizens submitted their vote in the 2006 Presidential Election using a direct recording electronic (DRE) system. Though they are widely used, little research has been done to prove they are more usable than more traditional methods of voting. This paper compares usability data from a DRE with that of other methods (level machines, punch cards, paper ballots).
Experiment 1:
The first experiment presented the usual DRE voting system. Subjects were presented first with an instruction screen. After that, they were able to vote on each item/proposition in the ballot. Navigating through each page was done using a "Next Page" and "Previous Page" button. After all items had been voted on, all of their selections were summarized on a screen so users could double-check their choices. From there, the ballot could be submitted. After submitting their votes, participants completed a survey (System Usability Scale, measuring satisfaction). The first experiment composed of two separate parts.
Experiment 1A:
In this experiment, the subjects were divided into two groups. The first group was instructed to vote whichever way that they wanted. The second group was given a piece of paper that instructed them how to vote on each issue. Each participant voted using the DRE and an additional method (lever machine, paper ballot, punch card).
Undirected, Directed with no roll-off.
Experiment 1B:
This experiment was similar to the previous, except for one aspect. The subjects were divided into three groups, instead of two. The third group was also given a piece of paper that instructed them how to vote on each issue, but on some issues they were told to not vote.
Undirected, Directed with no roll-off, Directed with moderate roll-off.
Results:
There wasn't a large distinction among the average voting times between the DRE and other methods. The only distinct improvement was with the lever machine. Also, people with more computer-experience took less time to vote on the DRE than other participants with less experience. Based on the results of the SUS, they found that participants preferred using the DRE to all other voting methods, regardless of any individual characteristics (age, computer-experience, etc). They also found that the DRE didn't reduce the number of voting errors that occurred. In conclusion, they found that changing the voting technology didn't result in less voting errors.
Experiment 2:
Voters rarely choose to vote on every issue that they are presented with on a ballot. The further they go down the ballot, the less likely it is that a voter will vote in a given race. Experiment 2 focused on comparing the traditional "sequential" voting design with a system where users could start on an overview page and jump to the individual elections that they wanted to vote on. Though it obviously would reduce the time users spent voting, would it also affect usability or increase voting errors?
Again, participants were divided into two groups. The first group voted using the "sequential" voting system. The second group used the new webpage-like system. The same information-conditions were used: undirected, directed with no roll-off, directed with moderate roll-off. In addition, a fourth condition was added--directed with additional roll-off. In this experiement, all participants voted three times: first using the DRE, then using one of the three traditional methods, then again with the same type of DRE. This time, no surveys were given after voting.
Results:
Of course, they found that the average completion time for the direct DRE (269.9s) was lower than that of the sequential DRE (442.3s); however, no reliable differences were found between the direct DRE and the other traditional voting methods. No differences were determined in any of the three directed information conditions. For the undirected condition, they found that the sequential voting method (910s) was much slower than the direct voting method (205s). This is because participants that used the direct DRE system voted in far fewer races than those using the sequential DRE.
They also found that voting errors occurred more often on the direct DRE than on the sequential DRE. This is due to the fact that almost 25% of participants using the direct DRE prematurely submitted their ballots before they intended. Regardless of the voting method used, over 34% of all ballots that were cast contained at least one error.
Though the direct DRE was much faster than the sequential DRE, the subjective usability ratings for the sequential system were higher. This was attributed to the fact that the direct DRE systems were inaccurate and resulted in more voting errors.
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