Monday, October 28, 2013

Grading systems -- how do you grade?

I just saw a post by Kevin Werbach that links to a post on the grading system used by Liz Lawley -- she gives only three grades: A for "good work," C for "mediocre but acceptable work" and F if "they really hadn’t mastered the material."

That got me thinking about grading. I will tell you how I grade and would like to hear how you grade.

For final grades, I curve students relative to the top person in the class, so they are not competing against each other. I also put them in heterogeneous groups and give significant bonuses to groups with low-variance, encouraging them to help each other.

Part of their grade is based on assignments. Since I give a lot of small, focused assignments, I had to devise a grading system that did not take a lot of time. I grade assignments as satisfactory and on time, satisfactory, but late, or not satisfactory. They get full credit for assignments that are satisfactory and on time and half credit for those that are satisfactory, but late. If they are not satisfactory, I explain why and they have the opportunity to re-submit a satisfactory answer for half credit. This method makes grading relatively quick and encourages students to keep up.

But, I am still grading at the course level, which is inappropriate for many subjects. For example, to say that someone received a C in an introductory statistics course means they did not learn significant parts of the material -- perhaps understanding descriptive statistics, but not hypothesis testing or estimation.

Instead of one grade, I'd prefer a fine-grained system in which one could, for example, pass "measures of central tendency," then "measures of variability," then "basic probability," etc. In that case, "passing" an introduction to statistics would mean passing each of a series of ordered modules and understanding all of the concepts and skills presented in the course.

I've advocated and used modular teaching material for many years, but always within the confines of the standard grading paradigm -- assign a letter grade from A to F for an entire course. With today's technology, we could combine modular teaching material with pass/fail grading at the module level. The technology is the easy part. Breaking up the traditional transcript -- our current system of grading and certification -- would be tough.

But, enough blue sky dreaming -- I am curious to know how others grade. I've outlined my grading system and that of Liz Lawley -- how do you grade?

Bill Gates talk to community college leaders

Earlier this month, Bill Gates addressed the Leadership Congress of the Association of Community College Trustees.

He described a few of the projects they have funded -- flipped classrooms, using MOOCs and other material:

We don’t have to have 20 different people in a large urban area all giving a lecture in the same introductory course. We can get the greatest lecturers in the English-speaking world, every student can listen to them – and the instructors who used to spend their time preparing and delivering lectures can become 21st century community college instructors.
This implies a different, but important role for instructors:
These instructors are gifted at relating to students, running small group learning sessions, and matching up students with the best resources available – the best lectures, the best problem sets, the best assessments. They have more time to get to know the students, explain difficult concepts, and trouble-shoot when students aren’t thriving. They are the architects and motivators of learning.

The smart use of technology doesn’t replace faculty – it redeploys them, to the benefit of the students.
Gates emphasized remedial classes and his funding of the Khan Academy seems like a good fit for the approach outlined in this talk. You can read a transcript of his presentation or watch this video:

Friday, October 25, 2013

PBS Frontline report provides context for the current NSA scandal

I figured everyone else was publishing information about NSA spying, so I had nothing to add, but I came across a PBS Frontline report "Top Secret America – 9/11 to the Boston Bombings," which provides context for the action of Edward Snowden. It aired on April 30, 2013.PBS describes the report as follows: "In the aftermath of the Boston Marathon bombings, Frontline investigates the vast maze of clandestine government efforts created after 9/11 for the purpose of hunting terrorists and preventing future attacks."

Here are a couple of quotes from the transcript:
NARRATOR: Ten years after September 11th--Pulitzer Prize-winning journalist Dana Priest investigates the creation of Top Secret America.

RICHARD IMMERMAN, Asst. Dpty. Director, DNI, 2007-08: What happens after 9/11 is this tremendous ramping up.

DANA PRIEST, The Washington Post: The money just came out of Congress- it was flying out.

ALLISON STANGER, Rohatyn Center for International Affairs: It’s shrouded in secrecy.

GARY SCHROEN, CIA, 1970-02: We weren’t going to play by the old set of rules.


NARRATOR: But finding the exact needle would take manpower, lots of it, and in a hurry. The NSA turned to a new force in the covert war, private contractors. (LP: one of which, Booz Allen Hamilton, employed Edward Snowden).

DANA PRIEST: You had this boom in the corporate intelligence world, as well, companies like CACI, Lockheed Martin, General Dynamics. Just all the old-fashioned industrial, “We’re building ships and submarines”-type corporations quickly moved into the intelligence and information space.

NARRATOR: The NSA spent billions of dollars on more than 480 private companies. Gen. Michael Hayden led the effort in the days right after 9/11.

Wednesday, October 16, 2013

MOOC competition is heating up -- two European MOOC providers are going live

I discussed the global nature of online education in an earlier post. While MOOCs started in the US, and US companies and universities have offered the majority of classes to date, online education will be a global market for providers as well as students.

Two European MOOC providers, iversity and Futurelearn, are going live this month. The first course offered by Futurelearn, a coalition of UK universities, starts October 21. It is an ecology course called "Fairness and nature: When worlds collide" and it will only last two weeks. I will enroll to get a look at the Futurelearn delivery platform.

Iversity began with a scholarship from the German Federal Ministry of Science and Technology and is now venture funded. They will be offering MOOCs by university professors from around the world and are launching with six courses this month. Their course promotion videos are innovative, for example, combining video and graphics and using 3D video, as shown below. I want to keep an eye on their platform as well.

Tuesday, October 15, 2013

Gallup poll on traditional versus online education in the U.S.

During the first week of October, Gallup polled U. S. adults on their opinion of online education. in the U. S.

They found that online education was rated as better than traditional education at providing value and a variety of courses. On the other hand, the respondents see student success as more likely in traditional classes. They also rate traditional classes as better at individualized instruction and delivering high-quality instruction from well-qualified instructors. They see traditional classes as more likely to have rigorous testing and grading that can be trusted, which correlates with a belief that they are more likely to be viewed positively by employers. Here is a summary of the results:

The survey was done over the phone (50% cell and 50% landline) and the results are weighted in proportion to U. S. demographics. Gallup says they are 95% confident that the results are within +/- four percent.

Five percent said they were currently taking an online course and they tended to be relatively young and focused on school work as opposed to job skills or recreation.

These results are indicative of general public opinion, which may give some insight into the future of public funding for online education as well as its worth in the job market, but I wish they would survey people who have recently or are currently taking a class online -- asking what they were taking, why they took it, whether it was massive, open, a traditional college class online, etc.

For this survey, I have the impression that many of the people who were taking online classes did so as part of a degree program, but that is not made clear. I hope Gallup will follow up with surveys of online students.

Saturday, October 12, 2013

Freedom House report -- "Freedom on the Net, 2013"

Freedom House publishes an annual report on Internet freedom and Freedom on the Net 2013 was published last week.

The report "headline" is an Internet freedom score for each of 60 nations. The score is based on:
  • Obstacles to Access—including infrastructural and economic barriers to access, legal and ownership control over internet service providers (ISPs), and independence of regulatory bodies;
  • Limits on Content—including legal regulations on content, technical filtering and blocking of websites, self-censorship, the vibrancy/diversity of online news media, and the use of ICTs for civic mobilization;
  • Violations of User Rights—including surveillance, privacy, and repercussions for online activity, such as imprisonment, extralegal harassment, or cyber attacks.
Here are the controls in effect in the top and bottom five scoring nations:

The USA rank will probably drop next year, reflecting the ongoing revelations of the extent of NSA Internet surveillance. (For the full list of national controls click here).

While the index is interesting, the meat of the report is in essays on the state of the Internet in the various nations. These are concise and well referenced. They focus on developments during the year, but are a good starting point to understanding the Internet in a nation.

The report also includes graphic presentations of the data, for example, an interactive map in which data is displayed when the cursor hovers over a nation:

Sunday, October 06, 2013

Chromebook + Chromecast = winner

In a recent test, I discoverd that my laptop was not fast enough to cast video from a browser tab to a Chromecast. The audio and video stuttered badly because, as you see here, the CPU was maxed out:

This was not surprising, since my laptop fails to meet Google's recommended specs for tab

But, I posted a query to the Chromecast community on Google Plus asking whether any Chromebooks could cast a video tab. I expected that the (very expensive) Google Pixel, which has an Intel i5 CPU, would be the only one that could, but I was wrong.

James Welbes commented that he was able to cast video tabs using his Samsung 550 Chromebook, which has a dual core Celeron processor. That led commenter Joe Phelps to speculate that "Chrome OS must have very little overhead." That makes a lot of sense -- it does not have to deal with things like overlapping windows and a local file system.

The next generation of Chromebooks has been announced.

I expect that they will all cast tabs well. If that is the case, and one of them has a decent keyboard and screen, I will use it in my den for watching video and in my Chromecast-equipped office for work.

The Pixel was a proof of concept and the new Chromebooks are the first production machines. I will still use laptop and desktop machines, but the Chromebook will get plenty of use.

Update 11/26/2013

Acer announced a $300 touch screen Chromebook today. (I believe the only other one is the expensive Google Pixel).  This sounds really cool, but it only has 2GB of RAM.  I keep a lot of tabs open so suspect that would be a performance constraint.

Saturday, October 05, 2013

A terrific article on the development of the iPhone

The New York Times magazine published an article by Fred Vogelstein on the development and announcement of the iPhone: And Then Steve Said, "Let There Be an iPhone."

The article describes an enormous challenge with 80-hour weeks and frayed tempers, the risks they took, the secrecy around the project and a fascinating behind the scenes look at the preparation for the risky on-stage demo Steve Jobs did at the product introduction (starting at 21m 3s -- watch at least through 24m 30s):

Here are a few quotes from the New York Times article to pique your interest:

It’s hard to overstate the gamble Jobs took when he decided to unveil the iPhone back in January 2007. Not only was he introducing a new kind of phone — something Apple had never made before — he was doing so with a prototype that barely worked.

Very rarely did I see him become completely unglued — it happened, but mostly he just looked at you and very directly said in a very loud and stern voice, ‘You are [expletive] up my company,’ or, ‘If we fail, it will be because of you.’

But every time Jobs and his executives examined the idea in detail, it seemed like a suicide mission. Phone chips and bandwidth were too slow for anyone to want to surf the Internet and download music or video over a cellphone connection.

Above all, Jobs didn’t want to partner with any of the wireless carriers.

Apple designed and built not one but three different early versions of the iPhone in 2005 and 2006.

No one had ever put a multitouch screen in a mainstream consumer product before

Jon Rubinstein, Apple’s top hardware executive at the time, says there were even long discussions about how big the phone would be.

The iPhone project was so complex that it occasionally threatened to derail the entire corporation. Many top engineers in the company were being sucked into the project, forcing slowdowns in the timetables of other work.

Big companies like Marvell, which made the Wi-Fi radio chip, and CSR, which provided the Bluetooth radio chip, hadn’t been told they were going to be in a new phone. They thought they were going to be in a new iPod. “We actually had fake schematics and fake industrial designs,” the engineer says.

Even people within the project itself couldn’t talk to one another.