Ph207x Homework Hotline

Registration numbers in Health and Numbers and Health and Environmental Change were similar in magnitude. As of September 8, 2013, edX had records of 61,181 students who had registered for Health in Numbers and 53,340 students who had registered for Health and Environmental Change. The difference can be attributed in part to registrations in Health in Numbers that have happened since the course “wrapped,” after all graded materials were due.

Figure 1 shows the cumulative registration for Health in Numbers and Health and Environmental Change. Health and Environmental Change had a longer enrollment period before the course began by over 60 days. Health in Numbers, however, had a slightly higher registration rate during the shorter period. They had different levels of enrollment when the course launched (34,970 for Health in Numbers and 45,390 for Health and Environmental Change) and similar numbers at 120 days after course launch, just after each course wrapped (54,007 for Health in Numbers and 53,340 for Health and Environmental Change).

Figure 1. Cumulative enrollment through 120 days after course launch for Health in Numbers (n=54,007) and Health and Environmental Change (n=53,340).

Since Health in Numbers started nine months before Health and Environmental Change, there was an almost ten-month span between the wrap of Health and Numbers and the data collection for this report and only three weeks between the wrap of Health and Environmental Change and data collection. During this post-wrap period, over 7,000 people signed up for Health in Numbers. We include these 7,000 post-wrap registrants from Health in Numbers in many of our analyses below because they are an interesting constituency to consider. Those who register after the due date cannot have a complete course experience—they did not have access to Professor Pagano’s textbook, the free version of Stata, the discussion forums, or the final exam, and they could not earn a certificate. However, they could view the lectures, submit answers to problems and view correct answers, and take the practice exams. These students could have a meaningful, self-directed, learning experience.

In Figures 2, 3 and 4, we present data about the demographic characteristics of students in Health and Numbers and Health and Environmental Change, and we compare these characteristics to the averaged percentages from the five other initial HarvardX large scale courses (Justice, Heroes, Computer Science, Health in Numbers, and Health and Environmental Change). Health and Environmental Change was one of the more gender-balanced courses among the initial HarvardX offerings, with 49% female registrants; Health in Numbers was more typical with 43% female registrants. The multiple course report has additional details about course-specific demographics for HarvardX and MITX courses.

Figure 2. Gender distribution in Health in Numbers (n=57,536; 3,645 missing), Health and Environmental Change (n=50,114; 3,226 missing) and the average distribution of five 2012–2013 HarvardX large-scale courses (n=384,060; 35,254 missing).

Figure 3. Distribution of highest degree earned in Health and Numbers (n=55,638; 5,5453 missing), Health and Environmental Change (n=48,262; 5,078 missing), and five HarvardX large-scale courses (n=368,579, 50,735 missing).

Figure 4. Age distribution of Health in Numbers (n=57,000; 4,181 missing), Health and Environmental Change (n=53,340; 3,740 missing), and the average of the first five HarvardX large-scale courses (n=342,048; 77,266 missing).

As with other HarvardX courses, registrants in the HSPH offerings were highly educated, especially in Health in Numbers. Over 85% of students registered for Health in Numbers held at least a Bachelor’s Degree. In terms of registrants’ highest degree attained, 36% of registrants had a Bachelor’s degree, an additional 38% had a Master’s degree, and an additional 12% of students possessed doctorates. The proportion of advanced degree holders (Master’s and PhD) in Health and Numbers was the highest of any of the first HarvardX courses. Health and Environmental Change was more typical of HarvardX courses: 39% of students had a Bachelor’s degree, an additional 29% held a Master’s degree, and an additional 6% had a PhD.

As expected, given their higher-than-average educational attainment, Health in Numbers skewed somewhat older than other HarvardX courses, with an especially high proportion of students in their 30s. Health and Environmental Change more closely tracked the average distribution of the first five large-scale HarvardX courses.

Both HSPH courses were global enterprises. Of the students with identifiable countries of residence (detected through geo-locating IP addresses and parsing self-reported addresses), 75% came from outside of the United States, with the largest second cohort in each country coming from India. The proportion of international students is higher than the other early HarvardX large-scale courses, where approximately two-thirds of identifiable registrants came from outside the United States.

Table 3. Country of residence for registrants with identifiable addresses in Health and Environmental Change (n=48,360; 4,980 missing) and Health in Numbers (n=58,520; 2,661 missing).

Of the students who registered for these HSPH courses, the degree and kind of participation varied considerably. Some students completed all the materials available in the course; others focused on videos and readings while avoiding assessments; and still others focused mostly on taking assessments. To illustrate these diverse course-taking patterns, Figures 5 and 6 show scatterplots of student activity on two dimensions. On the x-axis, we plot student grades, and on the y-axis, we plot the number of “chapters” that were viewed at least once by the student (the points in the plot are jittered to show density.) Chapters are the highest-level organizational unit in the edX courseware; Health in Numbers had 16 chapters, one for each of the 12 weeks, one for a practice exam, one for the real exam, one introduction, and one collection of videos from guest lecturers.

Figure 5. Scatterplot of grade and chapters viewed for Health in Numbers registrants (n=61,181).

Figure 6. Scatterplot of grade and chapters viewed for Health and Environmental Change registrants (n=53,340).

Within these plots, we identify four interesting categories of students and several interesting specific cases. In the top of the figure, we show those students who earned a certificate in the course. In the top right, we highlight a “completionist,” a student who had the highest possible grade and also viewed all of the chapters in the course. In the top left of this top section, we highlight an “optimizer,” a student who earned a certificate with a grade exactly at the cutoff score while opening a small number of chapters in the courseware.

In the lower sections of the plots, we show students who did not earn a certificate, and we distinguish between students who viewed both more and less than half of the chapters in the course. We define those who viewed more than half of the course but did not earn a certificate as “explorers.” In the bottom right, we highlight the students who viewed all of the chapters in the courseware but answered 0 graded questions correctly as “listeners,” borrowing an MIT term for auditors. We define those who viewed less than half of the courseware and did not earn a certificate as having “viewed” the course. In the bottom left, we define those students who viewed zero chapters as “only registered.” While these points are clustered in a small space on the scatterplot, the represent a substantial portion of students in each course: 22,327 in Health and Numbers and 30,496 in Health and Environmental Change.

One of the signature features of these plots is that students can be found at nearly every possible location in the possibility space. Some students focused on earning a certificate by targeting assessment questions; some students viewed all parts of the course, eschewing all assessment; some students dabbled in various dimensions; and some students successfully completed all parts of the course.

Motivated by this variation (found throughout all of the initial HarvardX courses), we defined four subsamples of participants to investigate in this series of HarvardX reports: Registrants, Viewers, Explorers, and Certified. In Figure 7, we present the numbers in each group as disjoint subsets in Health in Numbers and Health and Environmental Change.

Figure 7. Numbers of participants in Health in Numbers and Health and Environmental Change presented in four disjoint subsets of Only Registered, Only Viewed, Only Explored, and Certified.

Examining student demographics through the lens of these categories reveals patterns of some interest. Figure 8 shows that in Health in Numbers, the female percentage was lower overall (43%) but slightly higher for certificate earners at 46%.  In Health and Environment, the female percentage was higher overall (49%) but slightly lower for certificate earners at 45%.

Figure 8. Percentage of female students in four disjoint groups of Health in Numbers (n=61,181) and Health and Environmental Change (n=53,340).

We found a relationship between certificate attainment and level of education in both courses. In Figure 9, we show the distribution of the proportion of students with at least a Bachelor’s degree in our four disjoint subsets, and we see that in both courses—more strongly in Health in Numbers—certificate earners were disproportionately more highly educated. Students who earned a certificate in either course also tended to be older. The median age among only registered students was 27 in Health and Environmental Change and 29 in Health in Numbers. The median age among certified students was 29 in Health and Environmental Change and 31 in Health in Numbers.

Figure 9. Percentage of students with Bachelor’s degrees in four disjoint groups of Health in Numbers (n=61,181) and Health and Environmental Change (n=53,340).

Professors ‘amazed’ by level of student interaction online

February 21, 2013 – Beginning last October, thousands of students from around the globe began studying at Harvard School of Public Health (HSPH) in a totally new way. They studied biostatistics and epidemiology, the building blocks of public health research, at home or in cafés, at any time of day or night, for a few minutes at a time or for hours at a time—as part of HSPH’s first-ever course offered through edX, the online education platform.

The course—“Health in Numbers: Quantitative Methods in Clinical and Public Health Research” (PH207x)— was taught by [[Marcello Pagano]], professor of statistical computing, and E. Francis Cook, professor of epidemiology. Both were thrilled with the response to the course.

HSPH launching second edX course

Through edX, Harvard University and five other universities are partnering to offer online courses for free to students everywhere.

The initiative was launched in May 2012 by Harvard and MIT. Later, several other schools joined the consortium, including the University of California, Berkeley, the University of Texas system, Wellesley College, and Georgetown University.

The first edX course was offered in spring 2012; six were offered last fall. Of two fall Harvard courses, one was a Harvard School of Public Health (HSPH) course titled “Health in Numbers: Quantitative Methods in Clinical and Public Health Research” (PH207x); the other was an introductory computer science course. This spring HSPH is launching a second course, PH278x: Human Health and Global Environmental Change, taught by Aaron Bernstein, associate director of the Center for Health and the Global Environment at HSPH, and John Spengler, director of the Center and Akira Yamaguchi Professor of Environmental Health and Human Habitation in the Department of Environmental Health. The new public health course will examine how global environmental changes, such as climate change and biodiversity loss, may harm the health of billions of people worldwide—and will engage students in thinking about solutions

In fall 2012, edX offered eight courses. This spring, it’s offering 19. By next fall, edX organizers hope to develop 12 new full courses and as many as 50 “modules”— discrete online offerings such as a single lecture, lesson, or skills training.

“We were able to keep a huge number of people interested enough in the topics to stay with us for about three months and they spent, on average, about 12 hours a week on the course,” said Pagano.

[[David Hunter]], HSPH dean for academic affairs, said that the enthusiastic participation of HSPH in edX was aimed both at increasing the numbers of trained public health workers around the world and at improving teaching in the School’s residential degree programs.

“Online teaching not only increases our global reach, but it provides materials and methods that we hope will make classes at HSPH more flexible and student-centered,” Hunter said. He said the next priority is to have the other elements of the core master of public health curriculum available in edX format.

Signups and “meetups”

Of the 55,000 who initially signed up for PH207x, about 28,000 answered at least one question on a homework assignment—a sign of a student with “real interest,” Pagano said. Of the 28,000, 8,000—about 30%—completed the course, and 5,000 did well enough on the homeworks and final exam to officially get a certificate.

“This was a really dedicated and hard-working bunch of students,” said Cook.

More than a third of the 55,000 initial enrollees came from the United States. India was next highest, with 8,000 enrollees—about 15% of the total. Last November, edX arranged a “meetup” in Bangalore to give students a chance to virtually meet Cook and Pagano via Skype, discuss how the course was going with the teachers, and connect with other students. In Mumbai, about 150 PH207x students arranged their own meetup.

Big effort, positive student feedback

To prepare for PH207x, Pagano and Cook spent many hours filming lessons in the Leadership Studio on the 10th floor of the Kresge building at HSPH. Their mini-lectures—ranging in length from about 5 to 15 minutes—were paired with video labs presented by four teaching assistants: Lauren Hund, Elizabeth Mostofsky, Pamela Rist, and Brian Sharkey. “We could not have done this without them,” Pagano said.

Before the course began, Pagano and Cook wondered: Would students be as engaged as in a traditional course? Would they learn as much? How well would the online chat rooms—where students could post questions or comments, and the teachers, teaching assistants, and other students could respond—work??

The results were gratifying.

“We were impressed with the tenor of the course,” Pagano said. “The level of discussion and achievement was quite comparable to what we see when we teach our students here, live at HSPH, if not even better.”

“I was amazed by the amount of interaction, discussion, and support among the students in the chat rooms,” Cook said. “They taught themselves in many ways.” Added Pagano, “Wrong answers lasted a very short time before being challenged.”

Feedback from students was very positive. “That was a million-dollar lecture, sir,” one student said of one of Cook’s lectures. Another posted, “Marcello Pagano for President!”

Khushboo Gala, a medical student from Mumbai, wrote to thank Cook and Pagano—“not only on my behalf, but on the behalf of the thousands around the globe who have greatly benefited by your excellent teaching,” he wrote. “I … only now begin to comprehend how vastly important [statistics] is in the field of medicine.”

Benefits of ‘active learning’

Cook said the course taught him a lot, too—about teaching.

“I think the ‘chunk and test’ method we used—in which we present a small amount of material in a few minutes and then provide a few problems or homework sets for the students to gauge their understanding of the material before moving into the next topic—is a great way of teaching,” he said. “The next big challenge will be determining how we might ‘flip’ this course for HSPH students, whereby the students would view lectures on their own schedules and use class time for asking questions, doing problem sets, analyzing data, developing study proposals, or critiquing papers—with lots of interaction.”

The online course highlighted the benefits of “active learning,” Pagano said. Students could use applets (small applications that run within larger programs) to run their own simulations—rather than just digest simulations presented to them—which helped them explore and better understand concepts, he said.

“Plus, very importantly, students had complete control of the speed at which they received the material,” Pagano said. “They could literally speed up or slow down the speed at which the videos ran. They could stop them or replay them or skip them. They could pause them as they searched for information on the Internet. In other words, they did not just sit in class and sleep while the professor performed—they had to be active in learning the material.”

Before the course began Pagano was concerned about not being able to chat with students in class or in the cafeteria. But, he said, “It’s amazing how much of the student you can ‘see’ from the chat rooms. It was very much like the way pen pals formed friendships in the old days that lasted lifetimes.”

He added, “I had believed that the ‘brick and mortar’ classroom setting—where we sit in a lecture hall and absorb the pearls being cast at us—was the superior experience. Now I see that a good course can be delivered in another way.”

PH207x will be offered again in the future, probably in the fall of 2013.

— Karen Feldscher

0 Thoughts to “Ph207x Homework Hotline

Leave a comment

L'indirizzo email non verrà pubblicato. I campi obbligatori sono contrassegnati *