CU News
News from the University of Colorado in Boulder.
Mining big data for performance clues as a study guide
Jan 21st
forgetting with personalized content review
Computer software similar to that used by online retailers to recommend products to a shopper can help students remember the content they’ve studied, according to a new study by the University of Colorado Boulder.
The software, created by computer scientists at CU-Boulder’s Institute for Cognitive Science, works by tapping a database of past student performance to suggest what material an individual student most needs to review.
For example, the software might know that a student who forgot one particular concept but remembered another three weeks after initially learning them is likely to need to review a third concept six weeks after it was taught. When a student who fits that profile uses the software, the computer can pull up the most useful review questions.
“If you have two students with similar study histories for specific material, and one student couldn’t recall the answer, it’s a reasonable predictor that the other student won’t be able to either, especially when you take into consideration the different abilities of the two students,” said CU-Boulder Professor Michael Mozer, senior author of the study published in the journal Psychological Science.
The process of combing “big data” for performance clues is similar to strategies used by e-commerce sites, Mozer said.
“They know what you browsed and didn’t buy and what you browsed and bought,” Mozer said. “They measure your similarity to other people and use purchases of similar people to predict what you might want to buy. If you substitute ‘buying’ with ‘recalling,’ it’s the same thing.”
The program is rooted in theories that psychologists have developed about the nature of forgetting. Researchers know that knowledge—whether of facts, concepts or skills—slips away without review, and that spacing the review out over time is crucial to obtaining robust and durable memories.
Still, it’s uncommon for students to do the kind of extended review that favors long-term retention. Students typically review material that was presented only in the most recent unit or chapter—often in preparation for a quiz—without reviewing previous units or chapters at the same time.
This leads to rapid forgetting, even for the most motivated learners, Mozer said. For example, a recent study found that medical students forget roughly 25 to 35 percent of basic science knowledge after one year and more than 50 percent by the next year.
Over the last decade, Mozer has worked with University of California, San Diego, psychologist Harold Pashler, also a co-author of the new study, to create a computer model that could predict how spaced review affects memory. The new computer program described in the study is an effort to make practical use of that model.
Robert Lindsey, a CU-Boulder doctoral student collaborating with Mozer, built the personalized review program and then tested it in a middle school Spanish class.
For the study, Lindsey and Mozer divided the material students were learning into three groups. For material in a “massed” group, the students were drilled only on the current chapter. For material in a “generic-spaced” group, the students were drilled on the most recent two chapters. For material in a “personalized-spaced” group, the algorithm determined what material from the entire semester each student would benefit most from reviewing.
In a cumulative test taken a month after the semester’s end, personalized-spaced review boosted remembering by 16.5 percent over massed study and by 10 percent over generic-spaced review.
In a follow-up experiment, Mozer and his colleagues compared their personalized review program to a program that randomly quizzes students on all units that have been covered so far. Preliminary results show that the personalized program also outperforms random reviews of all past material.
So far, the program has been tested only in foreign language classes, but Mozer believes the program could be helpful for improving retention in a wide range of disciplines, including math skills.
It’s not necessary to have a prior database of student behavior to implement the personalized review program. Students can begin by using the program as a traditional review tool that asks random questions, and as students answer, the computer begins to search for patterns in the answers. “It doesn’t take long to get lots and lots of data,” Mozer said.
The research was funded by the National Science Foundation and the McDonnell Foundation.
-CU-
CU: State-of-the-art rec center is online
Jan 10th
The University of Colorado Boulder’s expansion of the Student Recreation Center, a project initiated by students, opens on Friday, Jan. 10, at 9 a.m. The southwest addition, the second and largest phase of the project, is located just north of the Ramaley Biology Building and east of Sewall Hall and will provide an additional 83,000 square feet of indoor recreational space.
The portions opening this month include a three-level weight and cardio area; three new wood floor all-purpose indoor courts for basketball, volleyball and badminton; a climbing wall and bouldering area; three fitness studios; wellness suites; new locker rooms and a spacious entrance and lobby.
“Recreation facilities have always been extremely popular among CU-Boulder students and over the years we found that our current facilities were not keeping up with the demand,” said Chris Schaefbauer , CU Student Government tri-executive. “In surveys of our peers we found CU students participate in recreational activities at a rate higher than the national average, but that our indoor recreation and fitness space per student was lower than the national average.”
The new ice rink opened in November and the Rental and Resource Center, which will rent camping and outdoor equipment, opens in mid-February. The final phase of the project, which consists of an indoor turf field, tennis courts, outdoor pool and the renovation of the existing basketball courts, is on track for completion in April.
The $63.5 million project was funded through the sale of bonds to be repaid through student fees collected over a 25-year period. In April 2011, the CU-Boulder student body voted to support the expansion and renovation of the Recreation Center. Nearly 37 percent of eligible student voters participated in the election, the largest ever student turnout, and over 70 percent voted “yes” to increase student fees in support of the expansion and renovation.
“With this state-of-the-art addition and the significant improvements to the Recreation Center, the students and the campus community will indeed have a remarkable facility at their disposal,” said Gary Chadwick, interim director of recreation facilities. “This is certainly an exciting time for the Recreation Services staff, who are anxious to begin offering the students the numerous opportunities that this center provides.”
Students will have 30,000 square feet of state-of-the-art cardiovascular and strength training equipment, a lower-level strength area, several additional cardiovascular and stretching spaces, and a “cardio equipment green zone” that captures user energy produced during exercises to feed back into the power grid and offset some power consumption within the facility.
A 4,000-square-foot-climbing wall built by Eldorado Designs contains areas for bouldering, lead climbing and top-rope climbing. The lead and top-rope areas reach up to 38 feet. The beginner to advanced bouldering terrain reaches a maximum height of 14 feet. The northeast corner consists of shot rock and is designed as an educational area for anchor building, lead climbing and multi-pitch climbing along with gear anchor building.
Three additional multipurpose fitness studios and a mind-body studio will provide members many opportunities to participate in fitness, mind-body, martial arts, Pilates reformer and dance classes.
The Wellness Suite will provide fitness assessments, nutrition clinics, personal training consultations, and the muscular skeletal clinic. The Wellness Suite also will serve to support student success in living a healthy, balanced lifestyle.
The campus community is invited to attend “Reconnect with the Rec” Jan. 21-24. CU-Boulder faculty and staff members are invited to use the facility for free during this time. The event will provide the opportunity to experience and learn more about the southwest addition. Festivities at this free event will include personal trainers and equipment vendors on site, group exercise demonstrations, facility tours, climbing wall competitions, giveaways, snacks and more. For a full schedule of events go to www.colorado.edu/recreation.
-CU-
CU: Gas-fired plants help clean the air
Jan 10th
Power plants that use natural gas and a new technology to squeeze more energy from the fuel release far less of the greenhouse gas carbon dioxide than coal-fired power plants do, according to a new analysis accepted for publication Jan. 8 in Earth’s Future, a journal of the American Geophysical Union. The so-called “combined cycle” natural gas power plants also release significantly less nitrogen oxides and sulfur dioxide, which can worsen air quality.
“Since more and more of our electricity is coming from these cleaner power plants, emissions from the power sector are lower by 20, 30 even 40 percent for some gases since 1997,” said lead author Joost de Gouw, an atmospheric scientist with NOAA’s Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado Boulder. NOAA is the National Oceanic and Atmospheric Administration.
De Gouw, who works at NOAA’s Earth System Research Laboratory (ESRL), and his NOAA and CIRES colleagues analyzed data from systems that continuously monitor emissions at power plant stacks around the country. Previous aircraft-based studies have shown these stack measurements are accurate for carbon dioxide (CO2) and for nitrogen oxides and sulfur dioxide. Nitrogen oxides and sulfur dioxide can react in the atmosphere to form tiny particles and ozone, which can cause respiratory disease.
To compare pollutant emissions from different types of power plants, the scientists calculated emissions per unit of energy produced, for all data available between 1997 and 2012. During that period of time, on average:
- Coal-based power plants emitted 915 grams (32 ounces) of CO2 per kilowatt hour of energy produced;
- Natural gas power plants emitted 549 grams (19 ounces) CO2 per kilowatt hour; and
- Combined cycle natural gas plants emitted 436 grams (15 ounces) CO2 per kilowatt hour.
In combined cycle natural gas plants, operators use two heat engines in tandem to convert a higher fraction of heat into electrical energy. For context, U.S. households consumed 11,280 kilowatt hours of energy, on average, in 2011, according to the U.S. Energy Information Agency. This amounts to 11.4 metric tons per year of CO2 per household, if all of that electricity were generated by a coal power plant, or 5.4 metric tons if it all came from a natural gas power plant with combined cycle technology.
The researchers reported that between 1997 and 2012, the fraction of electric energy in the United States produced from coal gradually decreased from 83 percent to 59, and the fraction of energy from combined cycle natural gas plants rose from none to 34 percent.
That shift in the energy industry meant that power plants, overall, sent 23 percent less CO2 into the atmosphere last year than they would have, had coal been providing about the same fraction of electric power as in 1997, de Gouw said. The switch led to even greater reductions in the power sector’s emissions of nitrogen oxides and sulfur dioxide, which dropped by 40 percent and 44 percent, respectively.
The new findings are consistent with recent reports from the Energy Information Agency that substituting natural gas for coal in power generation helped lower power-related carbon dioxide emissions in 2012.
The authors noted that the new analysis is limited to pollutants emitted during energy production and measured at stacks. The paper did not address levels of greenhouse gases and other pollutants that leak into the atmosphere during fuel extraction, for example. To investigate the total atmospheric consequences of shifting energy use, scientists need to continue collecting data from all aspects of energy exploration, production and use, the authors concluded.
Authors of the new paper, “Reduced Emissions of CO2, NOx and SO2 from U.S. Power Plants Due to the Switch from Coal to Natural Gas with Combined Cycle Technology,” are de Gouw (CIRES), David Parrish (NOAA ESRL), Greg Frost (CIRES) and Michael Trainer (NOAA).
CIRES is a joint institute of NOAA and CU-Boulder.
-CU-