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Harvard study: Large-scale US wind power would cause warming that would take roughly a century to offset

11 Oct

Argonne National Laboratory described wind power in Wind Energy Basics:

Basic information on wind energy and wind power technology, resources, and issues of concern.
Wind Energy and Wind Power
Wind is a form of solar energy. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth’s surface, and rotation of the earth. Wind flow patterns are modified by the earth’s terrain, bodies of water, and vegetative cover. This wind flow, or motion energy, when “harvested” by modern wind turbines, can be used to generate electricity.
How Wind Power Is Generated
The terms “wind energy” or “wind power” describe the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity to power homes, businesses, schools, and the like.
Wind Turbines
Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current. Simply stated, a wind turbine is the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
Wind Turbine Types
Modern wind turbines fall into two basic groups; the horizontal-axis variety, like the traditional farm windmills used for pumping water, and the vertical-axis design, like the eggbeater-style Darrieus model, named after its French inventor. Most large modern wind turbines are horizontal-axis turbines.
Turbine Components
Horizontal turbine components include:
• blade or rotor, which converts the energy in the wind to rotational shaft energy;
• a drive train, usually including a gearbox and a generator;
• a tower that supports the rotor and drive train; and
• other equipment, including controls, electrical cables, ground support equipment, and interconnection equipment.
Turbine Configurations
Wind turbines are often grouped together into a single wind power plant, also known as a wind farm, and generate bulk electrical power. Electricity from these turbines is fed into a utility grid and distributed to customers, just as with conventional power plants.
See Wind Energy Photos page for wind farm photographs.
Wind Turbine Size and Power Ratings
Wind turbines are available in a variety of sizes, and therefore power ratings. The largest machine has blades that span more than the length of a football field, stands 20 building stories high, and produces enough electricity to power 1,400 homes. A small home-sized wind machine has rotors between 8 and 25 feet in diameter and stands upwards of 30 feet and can supply the power needs of an all-electric home or small business. Utility-scale turbines range in size from 50 to 750 kilowatts. Single small turbines, below 50 kilowatts, are used for homes, telecommunications dishes, or water pumping.
See Wind Energy Photos page for wind turbine photographs.
Wind Energy Resources in the United States
Wind energy is very abundant in many parts of the United States. Wind resources are characterized by wind-power density classes, ranging from class 1 (the lowest) to class 7 (the highest). Good wind resources (e.g., class 3 and above, which have an average annual wind speed of at least 13 miles per hour) are found in many locations (see United States Wind Energy Resource Map). Wind speed is a critical feature of wind resources, because the energy in wind is proportional to the cube of the wind speed. In other words, a stronger wind means a lot more power. http://windeis.anl.gov/guide/basics/

Harvard Researchers found wind power could cause warming.

Science Daily reported in Large-scale US wind power would cause warming that would take roughly a century to offset:

All large-scale energy systems have environmental impacts, and the ability to compare the impacts of renewable energy sources is an important step in planning a future without coal or gas power. Extracting energy from the wind causes climatic impacts that are small compared to current projections of 21st century warming, but large compared to the effect of reducing US electricity emissions to zero with solar. Research publishing in the journal Joule on October 4 reports the most accurate modelling yet of how increasing wind power would affect climate, finding that large-scale wind power generation would warm the Continental United States 0.24 degrees Celsius because wind turbines redistribute heat in the atmosphere.
“Wind beats coal by any environmental measure, but that doesn’t mean that its impacts are negligible,” says senior author David Keith, an engineering and public policy professor at Harvard University. “We must quickly transition away from fossil fuels to stop carbon emissions. In doing so, we must make choices between various low-carbon technologies, all of which have some social and environmental impacts.”
“Wind turbines generate electricity but also alter the atmospheric flow,” says first author Lee Miller. “Those effects redistribute heat and moisture in the atmosphere, which impacts climate. We attempted to model these effects on a continental scale.”
To compare the impacts of wind and solar, Keith and Miller started by establishing a baseline for the 2012-2014 US climate using a standard weather forecasting model. Then they added in the effect on the atmosphere of covering one third of the Continental US with enough wind turbines to meet present-day US electricity demand. This is a relevant scenario if wind power plays a major role in decarbonizing the energy system in the latter half of this century. This scenario would warm the surface temperature of the Continental US by 0.24 degrees Celsius.
Their analysis focused on the comparison of climate impacts and benefits. They found that it would take about a century to offset that effect with wind-related reductions in greenhouse gas concentrations. This timescale was roughly independent of the specific choice of total wind power generation in their scenarios….
More than ten previous studies have now observed local warming caused by US wind farms. Keith and Miller compared their simulated warming to observations and found rough consistency between the observations and model.
They also compared wind power’s impacts with previous projections of solar power’s influence on the climate. They found that, for the same energy generation rate, solar power’s impacts would be about 10 times smaller than wind. But both sources of energy have their pros and cons.
“In terms of temperature difference per unit of energy generation, solar power has about 10 times less impact than wind,” says Miller. “But there are other considerations. For example, solar farms are dense, whereas the land between wind turbines can be co-utilized for agriculture.” The density of wind turbines and the time of day during which they operate can also influence the climatic impacts.
Keith and Miller’s simulations do not consider any impacts on global-scale meteorology, so it remains somewhat uncertain how such a deployment of wind power may affect the climate in other countries….
Keith and Miller also have a related paper, “Observation-based solar and wind power capacity factors and power densities,” being published in Environmental Research Letters on October 4, which validates the generation rates per unit area simulated here using observations. https://www.sciencedaily.com/releases/2018/10/181004112553.htm

Citation:

Large-scale US wind power would cause warming that would take roughly a century to offset
Date: October 4, 2018
Source: Cell Press
Summary:
Extracting energy from the wind causes climatic impacts that are small compared to current projections of 21st century warming, but large compared to the effect of reducing US electricity emissions to zero with solar. Researchers report the most accurate modelling yet of how increasing wind power would affect climate, finding that large-scale wind power generation would warm the Continental United States 0.24 degrees Celsius because wind turbines redistribute heat in the atmosphere.
Journal Reference:
Lee M. Miller, David W. Keith. Climatic Impacts of Wind Power. Joule, 2018; DOI: 10.1016/j.joule.2018.09.009
________________________________________
Cite This Page:
Cell Press. “Large-scale US wind power would cause warming that would take roughly a century to offset.” ScienceDaily. ScienceDaily, 4 October 2018. <www.sciencedaily.com/releases/2018/10/181004112553.htm>.

Here is the article summary from Joule:

Climatic Impacts of Wind Power
Author links open overlay panelLee M.Miller13David W.Keith12
Show more
https://doi.org/10.1016/j.joule.2018.09.009Get rights and content
Highlights
• Wind power reduces emissions while causing climatic impacts such as warmer temperatures
• Warming effect strongest at night when temperatures increase with height
• Nighttime warming effect observed at 28 operational US wind farms
• Wind’s warming can exceed avoided warming from reduced emissions for a century
Context & Scale
Wind power can impact the climate by altering the atmospheric boundary layer, with at least 40 papers and 10 observational studies now linking wind power to climatic impacts. We make the first comparison between the climatic impacts of large-scale wind power and site-scale observations, finding agreement that warming from wind turbines is largest at night. Wind power’s climatic impacts will continue to expand as more are installed.
Do these impacts matter? How do these impacts compare to the climate benefits of reducing emissions? We offer policy-relevant comparisons: wind’s climatic impacts are about 10 times larger than solar photovoltaic systems per unit energy generated. We explore the temporal trade-off between wind’s climatic impacts and the climate benefits it brings by reducing emissions as it displaces fossil fuels. Quantitative comparisons between low-carbon energy sources should inform energy choices in the transition to a carbon-free energy system.
Summary
We find that generating today’s US electricity demand (0.5 TWe) with wind power would warm Continental US surface temperatures by 0.24°C. Warming arises, in part, from turbines redistributing heat by mixing the boundary layer. Modeled diurnal and seasonal temperature differences are roughly consistent with recent observations of warming at wind farms, reflecting a coherent mechanistic understanding for how wind turbines alter climate. The warming effect is: small compared with projections of 21st century warming, approximately equivalent to the reduced warming achieved by decarbonizing global electricity generation, and large compared with the reduced warming achieved by decarbonizing US electricity with wind. For the same generation rate, the climatic impacts from solar photovoltaic systems are about ten times smaller than wind systems. Wind’s overall environmental impacts are surely less than fossil energy. Yet, as the energy system is decarbonized, decisions between wind and solar should be informed by estimates of their climate impacts. https://www.sciencedirect.com/science/article/pii/S254243511830446X

As with various energy sources there are pros and cons.

Energy.Gov lists the pros and cons of wind energy:

Advantages of Wind Power
• Wind power is cost-effective. Land-based utility-scale wind is one of the lowest-priced energy sources available today, costing between two and six cents per kilowatt-hour, depending on the wind resource and the particular project’s financing. Because the electricity from wind farms is sold at a fixed price over a long period of time (e.g. 20+ years) and its fuel is free, wind energy mitigates the price uncertainty that fuel costs add to traditional sources of energy.
• Wind creates jobs. The U.S. wind sector employed more than 100,000 workers in 2016, and wind turbine technician is one of the fastest-growing American jobs of the decade. According to the Wind Vision Report, wind has the potential to support more than 600,000 jobs in manufacturing, installation, maintenance, and supporting services by 2050.
• Wind enables U.S. industry growth and U.S. competitiveness. Wind has an annual economic impact of about $20 billion on the U.S. economy, The United States has a vast domestic resources and a highly-skilled workforce, and can compete globally in the clean energy economy.
• It’s a clean fuel source. Wind energy doesn’t pollute the air like power plants that rely on combustion of fossil fuels, such as coal or natural gas, which emit particulate matter, nitrogen oxides, and sulfur dioxide—causing human health problems and economic damages. Wind turbines don’t produce atmospheric emissions that cause acid rain, smog, or greenhouse gases.
• Wind is a domestic source of energy. The nation’s wind supply is abundant and inexhaustible. Over the past 10 years, cumulative wind power capacity in the United States increased an average of 30% per year, and wind now has the largest renewable generation capacity of all renewables in the United States.
• It’s sustainable. Wind is actually a form of solar energy. Winds are caused by the heating of the atmosphere by the sun, the rotation of the Earth, and the Earth’s surface irregularities. For as long as the sun shines and the wind blows, the energy produced can be harnessed to send power across the grid.
• Wind turbines can be built on existing farms or ranches. This greatly benefits the economy in rural areas, where most of the best wind sites are found. Farmers and ranchers can continue to work the land because the wind turbines use only a fraction of the land. Wind power plant owners make rent payments to the farmer or rancher for the use of the land, providing landowners with additional income.
CHALLENGES OF WIND POWER
• Wind power must still compete with conventional generation sources on a cost basis. Depending on how energetic a wind site is, the wind farm might not be cost competitive. Even though the cost of wind power has decreased dramatically in the past 10 years, the technology requires a higher initial investment than fossil-fueled generators.
• Good wind sites are often located in remote locations, far from cities where the electricity is needed. Transmission lines must be built to bring the electricity from the wind farm to the city. However, building just a few already-proposed transmission lines could significantly reduce the costs of expanding wind energy.
• Wind resource development might not be the most profitable use of the land. Land suitable for wind-turbine installation must compete with alternative uses for the land, which might be more highly valued than electricity generation.
• Turbines might cause noise and aesthetic pollution. Although wind power plants have relatively little impact on the environment compared to conventional power plants, concern exists over the noise produced by the turbine blades and visual impacts to the landscape.
• Turbine blades could damage local wildlife. Birds have been killed by flying into spinning turbine blades. Most of these problems have been resolved or greatly reduced through technological development or by properly siting wind plants. https://www.energy.gov/eere/wind/advantages-and-challenges-wind-energy

This Harvard study highlights there is no one energy solution for sustaining the global economy.

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Harvard and MIT study: So far, MOOC courses are not growing as fast as expected

15 Apr

Moi wrote in MOOCs are trying to discover a business model which works: Jon Marcus reported in the Washington Post article, Online course start-ups offer virtually free college. http://www.washingtonpost.com/local/education/online-course-startups-offer-virtually-free-college/2012/01/09/gIQAEJ6VGQ_story.html?wpisrc=emailtoafriend
The New York Times reported about the online education trend in the article, Online Enterprises Gain Foothold as Path to a College Degree http://www.nytimes.com/2011/08/25/education/25future.html?_r=1&emc=eta1
Whether MOOCS can develop a business model is discussed in the Economist article, The attack of the MOOCs: An army of new online courses is scaring the wits out of traditional universities. But can they find a viable business model? http://www.economist.com/news/business/21582001-army-new-online-courses-scaring-wits-out-traditional-universities-can-they
https://drwilda.com/2013/07/21/moocs-are-trying-to-discover-a-business-model-which-works/

Steve Kolowich reported in the Chronicle of Higher Education article, MOOCs Are Largely Reaching Privileged Learners, Survey Finds:

Most people who take massive open online courses already hold a degree from a traditional institution, according to a new paper from the University of Pennsylvania.
The paper is based on a survey of 34,779 students worldwide who took 24 courses offered by Penn professors on the Coursera platform. The findings—among the first from outside researchers, rather than MOOC providers—reinforce the truism that most people who take MOOCs are already well educated.
The Penn researchers sent the survey to students who had registered for a MOOC and viewed at least one video lecture. More than 80 percent of the respondents had a two- or four-year degree, and 44 percent had some graduate education.
The pattern was true not only of MOOC students in the United States but also learners in other countries. In some foreign countries where MOOCs are popular, such as Brazil, China, India, Russia, and South Africa, “80 percent of MOOC students come from the wealthiest and most well educated 6 percent of the population,” according to the paper.
In other developing countries, about 80 percent of the MOOC students surveyed already held college degrees—a number staggeringly out of proportion with the share of degree holders in the general population.
“The individuals the MOOC revolution is supposed to help the most—those without access to higher education in developing countries—are underrepresented among the early adopters,” write the paper’s six authors…
http://chronicle.com/blogs/wiredcampus/moocs-are-reaching-only-privileged-learners-survey-finds/48567

Research by Harvard and MIT found MOOCs are not growing in the ways expected.

Anya Kamenetz of NPR reported in New Research Shows Free Online Courses Didn’t Grow As Expected:

Today, much of that hype has subsided (though best-selling authors and newspaper columnists are still making the case that “the end of college” is nigh). And new research on 1.7 million MOOC participants offers a more nuanced view of just what these courses are and could become.

One of the biggest MOOC platforms, edX, is run jointly as a nonprofit by Harvard and MIT. And researchers at both schools have been poring over the data from everyone who participated in 68 courses over more than two years. That’s 10 million participant-hours. Here’s what they found.

A Lot Of Teachers And A Lifeline

In one survey of a subset of users, 39 percent identified as current or former teachers, and one-in-five had taught the subject they were studying. This finding supports the general profile of MOOCsters as being already well-educated….

The study also found extreme over-representation among citizens of Greece and Spain — not only taking courses but also paying for certification. During the period under study, Greek universities were forced to suspend operations due to austerity measures, and budget cuts in Spain led to national student protests. As a result, did students look online for an education alternative? It’s a question for future research, the authors agree.

Linear, Not Exponential Growth

The first MOOCs had over 100,000 registrants each. Predictions were made (and millions of dollars invested) based on the idea that participation would be in the hundreds of millions by now. Actual interest is more modest.

So what happens now — given MOOCs have fallen far short of those early, lofty expectations?

….Some colleges are looking to expand on-campus applications of MOOCs. Reich points out that 83 percent of MIT undergrads are taking a class that uses MITx resources in some way.
Paid certificates for these online courses are another potential answer, though Reich says they’re likely to be most useful in a minority of fast-changing, highly technical fields.

Andrew Ho, a lead author of the paper at Harvard, thinks the value of certificates will increase… ”

The simplest answer to “What happens now?” is this: Despite lingering doubts about the power and profitability of MOOCs, companies and universities are still spending significant resources to create and support them for millions of people, in nearly every country, for free. It’s an investment, for now, on faith…. http://www.npr.org/blogs/ed/2015/04/11/397295495/the-future-of-free-online-courses-new-research-from-mit-and-harvard

Citation:

HarvardX and MITx: Two Years of Open Online Courses Fall 2012-Summer 2014

Andrew Dean Ho
Harvard University; Harvard University – HarvardX

Isaac Chuang
Massachusetts Institute of Technology (MIT) – Office of Digital Learning

Justin Reich

Harvard University – HarvardX; Harvard University – Berkman Center for Internet & Society

Cody Austun Coleman

Massachusetts Institute of Technology (MIT) – Electrical Engineering and Computer Science

Jacob Whitehill

Harvard University

Curtis G Northcutt

Massachusetts Institute of Technology (MIT)

Joseph Jay Williams

Harvard University

John D Hansen

Harvard University

Glenn Lopez

Harvard University

Rebecca Petersen

Harvard University – HarvardX

March 30, 2015

Abstract:

What happens when well-known universities offer online courses, assessments, and certificates of completion for free? Early descriptions of Massive Open Online Courses (MOOCs) have emphasized large enrollments, low certification rates, and highly educated registrants. We use data from two years and 68 open online courses offered by Harvard University (via HarvardX) and MIT (via MITx) to broaden the scope of answers to this question. We describe trends over this two-year span, depict participant intent using comprehensive survey instruments, and chart course participation pathways using network analysis. We find that overall participation in our MOOCs remains substantial and that the average growth has been steady. We explore how diverse audiences — including explorers, teachers-as-learners, and residential students — provide opportunities to advance the principles on which HarvardX and MITx were founded: access, research, and residential education.
Number of Pages in PDF File: 37
Keywords: MOOC, massive open online course, HarvardX, MITx, edX, online learning, distance education, higher education, residential learning

Here is the press release from Harvard and MIT:

Massive Study from Harvard and MIT on MOOCs Provides New Insights on an Evolving Space
April 1, 2015

Since “Year of the MOOC” became a catchphrase in 2012, massive open online courses have had their fans and detractors. Some have claimed that online learning is a “disruptive revolution” and a harbinger of the end of residential colleges, while others have called MOOCs “mere marketing” at best or an abject failure at worst, singling out low completion rates.

Expanded data and research about MOOC participants and evidence-based assessments of online learning trends might, however, begin to move the conversation beyond anecdotes and heated opinions.
Today, a joint Harvard and MIT research team published one of the largest investigations of MOOCs (massive open online courses) to date. Building on their prior work—a January 2014 report describing the first year of open online courses launched on edX, a non-profit learning platform founded by the two institutions—the latest effort incorporates another year of data, bringing the total to nearly 70 courses in subjects from programming to poetry.

“We explored 68 certificate-granting courses, 1.7 million participants, 10 million participant-hours, and 1.1 billion participant-logged events,” said the study’s co-lead author Andrew Ho, a professor at the Harvard Graduate School of Education and chair of the HarvardX research committee. The research team also used surveys to ¬gain additional information about participants’ backgrounds and their intentions.

Ho and MIT’s Isaac Chuang, professor of physics, professor of electrical engineering and computer science, and senior associate dean of digital learning, led a group effort that delved into the demographics of MOOC learners, analyzed participant intent, and looked at patterns that “serial MOOCers,” or those taking more than one course, tend to pursue.

“What jumped out for me was the survey that revealed that in some cases as many as 39% of our learners are teachers,” said Chuang. “This finding forces us to broaden our conceptions of who MOOCs serve and how they might make a difference in improving learning.”

Key Findings

The researchers conducted a trend analysis that showed a rising share of female, US-based, and older participants, as well as a survey analysis of intent, revealing that almost half of registrants were not interested in or unsure about certification. In this study, the researchers redefined their population of learners from those who simply registered for courses (and took no subsequent action) — a metric used in prior findings and often cited by MOOC providers — to those who participated (i.e., by logging into the course at least once.)

Participation in HarvardX and MITx open online courses has grown steadily, while participation in repeated courses has declined and then stabilized
From July 24, 2012, through on September 21, 2014, the end of the study period, an average of 1,300 new participants joined a HarvardX or MITx course each day, for a total of 1 million unique participants and 1.7 million total participants. With the increase in second and third versions of courses, the researchers found that participation in second versions declined by 43%, while there was stable participation between versions two and three. There were outliers, such as the HarvardX course CS50x, “Introduction to Computer Science,” which doubled in size, perhaps due to increased student flexibility: Students in this course could participate over a year-long period at their own pace and complete at any time.

A slight majority of MOOC takers are seeking certification, and many participants are teachers
Among the one-third of participants who responded to a survey about their intentions, 57% stated their desire to earn a certificate; nearly a quarter of those respondents went on to earn certificates. Further, among participants who were unsure or did not intend to earn a certificate, 8% ultimately did so. These learners appear to have been inspired to finish a MOOC even after initially stating that they had no intention of doing so.

Among 200,000 participants who responded to a survey about teaching, 39% self-identified as a past or present teacher. 21% of those teachers reported teaching in the course topic area. The strong participation by teachers suggests that even participants who are uninterested in certification may still make productive use of MOOCs.

Academic areas matter when it comes to participation, certification, and course networks
Participants were drawn to computer science courses in particular, with per-course participation numbers nearly four times higher than courses in the humanities, sciences, and social sciences. That said, certificate rates in computer science and other science- and technology-based offerings (7% and 6%, respectively) were about half of those in the humanities and social sciences.

The larger data sets also allowed the researchers to study those participating in more than one course, revealing that computer science courses serve as hubs for students, who naturally move to and from related courses. Intentional sequencing, as was done for the 10-part HarvardX Chinese history course “ChinaX,” led to some of the highest certification rates in the study. Other courses with high certification rates were “Introduction to Computer Science” from MITx and “Justice” and “Health in Numbers” from HarvardX.

Those opting for fee-based ID-verified certificates certify at higher rates
Across 12 courses, participants who paid for “ID-verified” certificates (with costs ranging from $50 to $250) earned certifications at a higher rate than other participants: 59%, on average, compared to 5%. Students opting for the ID-verified track appear to have stronger intentions to complete courses, and the monetary stake may add an extra form of motivation.

Questions and Implications

Based upon these findings, Chuang and Ho identified questions that might “reset and reorient expectations” around MOOCs.

First, while many MOOC creators and providers have increased access to learning opportunities, those who are accessing MOOCs are disproportionately those who already have college and graduate degrees. The researchers do not necessarily see this as a problem, as academic experience may be a requirement in advanced courses. However, to serve underrepresented and traditionally underserved groups, the data suggest that proactive strategies may be necessary.

“These free, open courses are phenomenal opportunities for millions of learners,” Ho emphasized, “but equity cannot be increased just by opening doors. We hope that our data help teachers and institutions to think about their intended audiences, and serve as a baseline for charting progress.”
Second, if improving online and on-campus learning is a priority, then “the flow of pedagogical innovations needs to be formalized,” said Chuang. For example, many of the MOOCs in the study used innovations from their campus counterparts, like physics assessments from MIT and close-reading practices from Harvard’s classics courses. Likewise, residential faculty are using MOOC content, such as videos and assessment scoring algorithms, in smaller, traditional lecture courses.
“The real potential is in the fostering of feedback loops between the two realms,” said Chuang. “In particular, the high number of teacher participants signals great potential for impact beyond Harvard and MIT, especially if deliberate steps could be taken to share best practices.”

Third, advancing research through MOOCs may require a more nuanced definition of audience. Much of the research to date has done little to differentiate among the diverse participants in these free, self-paced learning environments.

“While increasing completion has been a subject of interest, given that many participants have limited, uncertain, or zero interest in completing MOOCs, exerting research muscle to indiscriminately increase completion may not be productive,” explained Ho. “Researchers might want to focus more specifically on well-surveyed or paying subpopulations, where we have a better sense of their expectations and motivations.”

More broadly, Ho and Chuang hope to showcase the potential and diversity of MOOCs and MOOC data by developing “Top 5” lists based upon course attributes, such as scale (an MIT computer science course clocked in with 900,000 participant hours); demographics (the MOOC with the most female representation is a museum course from HarvardX called “Tangible Things,” while MITx’s computing courses attracted the largest global audience); and type and level of interaction (those in ChinaX most frequently posted in online forums, while those in an introduction to computer science course from MITx most frequently played videos.)

“These courses reflect the breadth of our university curricula, and we felt the need to highlight their diverse designs, philosophies, audiences, and learning outcomes in our analyses,” said Chuang. “Which course is right for you? It depends, and these lists might help learners decide what qualities in a given MOOC are most important to them.”
Additional authors on the report included

Justin Reich, Jacob Whitehill, Joseph Williams, Glenn Lopez, John Hansen, and Rebecca Petersen from Harvard; and Cody Coleman and Curtis Northcutt from MIT.

With any education opportunity the prospective student and their family must do their homework and weigh the pros and cons of the institution with with the student’s goals and objectives. In answer to the question of whether online college is a threat to traditional bricks and mortar universities, it depends. The market will answer that question because many students do not attend college to receive a liberal arts education, but to increase employment opportunities. If the market accepts badges and certificates, then colleges may be forced to look at the costs associated with a traditional college degree.

Related:

Verifying identity for online courses

https://drwilda.com/2012/04/15/verifying-identity-for-online-courses/

Will ‘massive open online courses’ (MOOCS) begin to offer credit?

https://drwilda.com/2012/11/14/will-massive-open-online-courses-moocs-begin-to-offer-credit/

Is online higher ed a threat to bricks and mortar colleges?

https://drwilda.com/2012/09/17/is-online-higher-ed-a-threat-to-bricks-and-mortar-colleges/

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Dr. Wilda says this about that ©

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Harvard study: Cheating students are more likely to want to work for government

25 Nov

Cheating is increasingly a concern in education. Some colleges in an attempt to curb academic dishonesty on campus are beginning to employ methods one has usually associated with Las Vegas casinos. Minnesota State University Mankato has an excellent newsletter article about academic dishonesty. Richard C. Schimming writes in Academic Dishonesty:

A recent survey found that 1/3 of all students admitted to cheating on an examination, 1/2 admitted to cheating on a class assignment, 2/3 admitted to cheating at least once during their college career, and 2/3 have seen classmates cheat on exams or assignments. Paradoxically, 3/4 of those in that survey believe that cheating is not justified under any circumstances. Finally, 1/2 of the students surveyed believe that the faculty of their university do not try to catch cheaters…
http://www.mnsu.edu/cetl/teachingresources/articles/academicdishonesty.html

For some students, cheating starts early. By the time some kids reach college they have already established a pattern of cheating. ABC News has a good report, A Cheating Crisis in America’s Schools http://abcnews.go.com/Primetime/story?id=132376&page=1 https://drwilda.wordpress.com/2011/12/21/cheating-in-schools-goes-high-tech/

Emily Alpert Reyes reported in the L.A. Times article, Cheating students more likely to want government jobs, study finds:

College students who cheated on a simple task were more likely to want government jobs, researchers from Harvard University and the University of Pennsylvania found in a study of hundreds of students in Bangalore, India.
Their results, recently released as a working paper by the National Bureau of Economic Research, suggest that one of the contributing forces behind government corruption could be who gets into government work in the first place.
For instance, “if people have the view that jobs in government are corrupt, people who are honest might not want to get into that system,” said Rema Hanna, an associate professor at the Kennedy School of Government at Harvard. To combat that problem, governments may need to find new ways to screen people seeking jobs, she said.
Researchers ran a series of experiments with more than 600 students finishing up college in India. In one task, students had to privately roll a die and report what number they got. The higher the number, the more they would get paid. Each student rolled the die 42 times.
Although researchers do not know for sure if any one student lied, they could tell whether the numbers each person reported were wildly different than what would turn up randomly — in other words, whether there were a suspiciously high number of 5s and 6s in their results.
Cheating seemed to be rampant: More than a third of students had scores that fell in the top 1% of the predicted distribution, researchers found. Students who apparently cheated were 6.3% more likely to say they wanted to work in government, the researchers found.
“Overall, we find that dishonest individuals — as measured by the dice task — prefer to enter government service,” wrote Hanna and coauthor Shing-yi Wang, an assistant professor at the University of Pennsylvania’s Wharton School.
They added, “Importantly, we show that cheating on this task is also predictive of fraudulent behaviors by real government officials.”
The same test, given to a smaller set of government nurses, showed that those who appear to have cheated with the dice were also more likely to skip work. Previous studies suggest that the bulk of such absenteeism is fraudulent, Hanna said.
Researchers also ran other tests to gauge character: In another experiment, students played a game in which they could send a message anonymously to another player, either telling them honestly what move would earn them more money, or dishonestly nudging them toward a worse choice. Tricking the other student would help them gain more money.
http://www.latimes.com/science/sciencenow/la-sci-sn-cheating-students-government-jobs-corruption-20131118,0,2929974.story#ixzz2ldYrFkMY

Citation:

Dishonesty and Selection into Public Service
Rema Hanna, Shing-Yi Wang
NBER Working Paper No. 19649
Issued in November 2013
NBER Program(s): DEV
In this paper, we demonstrate that university students who cheat on a simple task in a laboratory setting are more likely to state a preference for entering public service. Importantly, we also show that cheating on this task is predictive of corrupt behavior by real government workers, implying that this measure captures a meaningful propensity towards corruption. Students who demonstrate lower levels of prosocial preferences in the laboratory games are also more likely to prefer to enter the government, while outcomes on explicit, two-player games to measure cheating and attitudinal measures of corruption do not systematically predict job preferences. We find that a screening process that chooses the highest ability applicants would not alter the average propensity for corruption among the applicant pool. Our findings imply that differential selection into government may contribute, in part, to corruption. They also emphasize that screening characteristics other than ability may be useful in reducing corruption, but caution that more explicit measures may offer little predictive power.
You may purchase this paper on-line in .pdf format from SSRN.com ($5) for electronic delivery.

Theories about why students cheat range from character issues to mental issues.

Sora Song of Time.Com discusses the inevitable study in the article, Profiling Student Cheaters: Are the Psychopaths?

Psychologists at the University of British Columbia found that students who cheated in high school and college were likely to meet the criteria for psychopathic personality – the type that tends toward a range of bad behaviors, like alcohol and drug abuse, bullying and reckless driving. It’s the same impulsive, callous and antisocial personality that characterizes criminal psychopaths, though, to be fair, student cheaters scored a lot lower on psychopathy questionnaires than actual criminal offenders. (More on Time.com: Video: Giving Dropouts a Second Chance)
The researchers found that academic cheaters also scored high in two other personality traits: narcissism (people who suffer from grandiosity, self-centeredness and an outsized sense of entitlement) and Machiavellianism (cynical, amoral types who make it a habit to manipulate others). But of the three disordered personalities – together known colorfully as the Dark Triad – psychopathy was the only trait significantly associated with student cheating.
The new paper, published in the Journal of Experimental Psychology: Applied, describes the results of a series of three studies involving nearly 600 college students. (Read a PDF of the paper here.) In each, the volunteers were asked to fill out anonymous personality questionnaires; some participants also took tests of intelligence. Personality questions included: “I like to be the center of attention” (i.e., I may be a narcissist), “It’s hard to get ahead without cutting corners here and there” (Machiavellianism), and “I have attacked someone with the goal of hurting them” (psychopathy). http://healthland.time.com/2010/09/20/profiling-student-cheaters-are-they-psychopaths/

The conclusion of the study is that the only thing which can be done is to make it impossible for the psychopath to cheat since they obviously have no impulse control and an appeal to values doesn’t work. One of the frightening prospects highlighted by the article is that it is possible to screen for psychopathic traits in people, but it probably wouldn’t be ethical for schools to do so. So, like the chicken and the egg riddle, society is back at placing the emphasis on strong families, values, and a K-12 education which sets some perimeters. Certainly something to think about.

Shouldn’t those who work for the government be interested in public service instead of than self-service? Something else to think about.

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New Harvard study about impact of teachers

8 Jan

The Guide to Teacher Quality lists several key attributes of a quality teacher:

WHAT WE KNOW ABOUT TEACHER QUALITY

Experience is very important. The ability of a new teacher to support student learning

increases greatly during his/her first year of teaching and continues to grow through at least the

first several years of teaching (Clotfelter, Ladd & Vigdor, 2007; Clotfelter, Ladd & Vigdor, 2004;

Hanushek et al., 1998).

Teacher attrition matters. Districts and schools with relatively high rates of teacher

attrition are likely to have more inexperienced teachers and, as a result, instructional quality

and student learning suffer (Alliance for Quality Teaching, 2008).

Ability matters. Teachers with higher scores on college admission or licensure tests as well

as those from colleges with more selective admission practices are better able to support student

learning (Gitomer, 2007; Rice, 2003; Wayne and Youngs, 2003; Reichardt, 2001; Ferguson

& Ladd, 1996; Greenwald, Hedges & Laine, 1996).

Teachers’ subject matter knowledge helps students learn. Students learn when their

teacher knows the subject, particularly in secondary science and mathematics (Floden &

Meniketti, 2006; Rice, 2003; Wayne and Youngs, 2003; Reichardt, 2001).

Preparation and training in how to teach makes a difference. Knowing how to teach

improves student learning, particularly when a teacher is in his/her first years of teaching (Rice,

2003; Allen, 2003; Boyd, Grossman, Lankford, Loeb & Wyckoff, 2005).

Teacher diversity may also be important. There is emerging evidence that students learn

better from teachers of similar racial and ethnic background (Dee, 2004; Dee, 2001; Hanushek

et al. 1998).

One of the important attributes is the subject matter knowledge of the teacher. These findings are particularly important in light of the study, The Long-Term Impacts of Teachers: TeacherValue-Added and Student Outcomes in Adulthood by Raj Chetty, Harvard University and NBER , John N. Friedman, Harvard University and NBER, and Jonah E. Rockoff, Columbia University and NBER .

Here is a portion of the executive summary:

Many policy makers advocate increasing the quality of teaching, but there is considerable debate about the best way to measure and improve teacher quality. One method is to evaluate teachers based on their impacts on students’ test scores, commonly termed the “value-added” (VA) approach. A teacher’s value-added is defined as the average test-score gain for his or her students, adjusted for differences across classrooms in student characteristics such as prior scores. School districts from Washington D.C. to Los Angeles have begun to use VA to evaluate teachers. Proponents argue that using VA can improve student achievement (e.g. Hanushek 2009), while critics argue that test score gains are poor proxies for a teacher’s true quality (e.g. Baker et al. 2010).

The debate about VA stems from two fundamental questions. First, does VA accurately measure teachers’ impacts on scores or does it unfairly penalize teachers who may systematically be assigned lower achieving students? Second, do high VA teachers improve their students’ long-term outcomes or are they simply better at teaching to the test? Researchers have not reached a consensus about the accuracy and long-term impacts of VA because of data and methodological limitations.

We address these two questions by tracking one million children from a large urban school district from 4th grade to adulthood. We evaluate the accuracy of standard VA measures using several methods, including natural experiments that arise from changes in teaching staff. We find that when a high VA teacher joins a school, test scores rise immediately in the grade taught by that teacher; when a high VA teacher leaves, test scores fall. Test scores change only in the subject taught by that teacher, and the size of the change in scores matches what we predict based on the teacher’s VA. These results establish that VA accurately captures teachers’ impacts on students’ academic achievement and thereby reconcile the conflicting conclusions of Kane and Staiger (2008) and Rothstein (2010). These methods provide a simple yet powerful method to estimate the bias of value-added models in any district; interested readers can download computer code to implement these tests from this link.

In the second part of our study, we analyze whether high VA teachers also improve students’ long-term outcomes. We find that students assigned to higher VA teachers are more successful in many dimensions. They are more likely to attend college, earn higher salaries, live in better neighborhoods, and save more for retirement. They are also less likely to have children as teenagers.

Teachers’ impacts on students are substantial. Replacing a teacher whose true VA is in the bottom 5% with a teacher of average quality would generate lifetime earnings gains worth more than $250,000 for the average classroom. VA estimates are less reliable when they are based on data from a small number of classes. However, even after observing teachers’ impacts on test scores for one year, estimates of VA are reliable enough that such personnel changes would yield large gains on average.

Teachers have large impacts in all the grades we analyze (4 to 8), implying that the returns to education remain large well beyond early childhood. Teachers’ impacts on earnings are also similar in percentage terms for students from low and high income families. As a rough guideline, parents should be willing to pay about 25% of their child’s income at age 28 to switch their child from a below-average (25th percentile) to an above-average (75th percentile) teacher. For example, parents whose children will earn around $40,000 in their late 20s should be willing to pay $10,000 to switch from a below-average to an above-average teacher for one grade, based on the expected increase in their child’s lifetime earnings.

Overall, our study shows that great teachers create great value – perhaps several times their annual salaries – and that test score impacts are helpful in identifying such teachers. However, more work is needed to determine the best way to use VA for policy. For example, using VA in teacher evaluations could induce undesirable responses that make VA a poorer measure of teacher quality, such as teaching to the test or cheating. There will be much to learn about these issues from school districts that start using VA to evaluate teachers. Nevertheless, it is clear that improving the quality of teaching – whether using value-added or other tools – is likely to have large economic and social returns.

See, Annie Lowrey’s New York Times article, Big Study Links Good Teachers to Lasting Gain

Teachers also have some thoughts about effective teaching. Valerie Strauss of the Washington Post has a guest column written by teacher Larry Ferlazzo. In Teachers: What We Need to Do to Fix the Schools

Citation:

Executive Summary of National Bureau of Economic Research Working Paper No. 17699, December 2011

THE LONG-TERM IMPACTS OF TEACHERS: TEACHER VALUE-ADDED AND STUDENT OUTCOMES IN ADULTHOOD

Raj Chetty, Harvard University and NBER

John N. Friedman, Harvard University and NBER

Jonah E. Rockoff, Columbia University and NBER

Executive Summary

Manuscript (NBER         WP17699)

Presentation Slides

STATA Code

Every child has a right to a good basic education. In order to ensure that every child has a good basic education, there must be a quality teacher in every classroom.

See:

Is it true that the dumbest become teachers?

https://drwilda.wordpress.com/2011/12/09/is-it-true-that-the-dumbest-become-teachers/

A Review of the Literature Regarding Teacher’s Subject Matter Knowledge

The Importance of Teacher Disposition

The Guide to Teacher Quality

Teacher Quality

What Comprises High Quality Teacher Education?

Educational Testing Services’ Where We Stand on Teacher Quality

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