Author Archives: Vince

Privacy, what privacy?

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It is possible to identify anonymous customers with only data about four purchases.

Scientists showed they can identify you with more than 90 percent accuracy by looking at just four purchases, three if the price is included – and this is after companies “anonymized” the transaction records, saying they wiped away names and other personal details.

Wow!

My daughter came home yesterday and told me about a web site that presents information about people. We typed in my name, which is fairly unique, it displayed information about where I have lived. She was alarmed. The information was obtained by publicly available knowledge, such as home purchases. There is no privacy anymore. She better understands why I do not want her to use her full name in usernames, such as email.

Cold Spell

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It was 11 degrees F this morning when I drove my daughter to school. We didn’t make her walk to school. Her generation is so coddled. When I was her age …

But it is quite cold here. Our upstairs HVAC that is in the uninsulated attic stopped working this morning because the drain line froze. The good news is the work is still under warranty and we aren’t heating the attic.

I got the following email yesterday.

Good Afternoon,

Please pass along the following important energy conservation message to all building occupants.

Anticipated cold temperatures on Thursday and Friday will challenge power delivery systems for Duke Energy, the main provider of campus electricity. To help maintain power supply in our region, please limit non-essential campus energy use on Jan. 8 and 9:

  • Turn off and unplug office equipment and appliances that are not vital or not in use
  • Ensure all exterior windows and doors are closed
  • Turn off lights in rooms that are not in use
  • Shut off all space heaters
  • Close lab fume hood sashes that are not in use

These actions will save energy on campus and help maintain reliable power supply during extreme conditions. For more ways to save energy, visit go.ncsu.edu/SaveEnergy

It is somewhat disturbing that our electric grid is this fragile.

Scientists are not that smart

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NY mag has posted an essay by Chad Orzel about scientists and society. I found it very thought provoking, but somewhat discouraging. For example, he notes that he plays basketball and enjoys even though he will never make the NBA but “science is something you’re expected to give up unless you’re ‘really’ smart enough to make it your career.”

I first encountered Prof Orzel through his book How to Teach Physics to Your Dog. My then 14-year-old daughter read it and loved it. Alas, her next experience with physics (high school class) quenched the passion that was ignited by the book.

Final grades

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Nearly every course one or more students send an email similar to the below immediately after final grades are posted.

My score is just below the cut off for a higher grade. Can you give me the higher grade?

The answer I usually give is

In every course there is someone who is has the highest score in a particular grade, this course it happens to be you.

Offense can be taken from such a curt reply, but none is meant. In fact it is a gracious reply because the question the student asked is wrong for at least two reasons. First, the situation (a student has the highest grade below a cutoff) is expected and unavoidable. If not that this student, then some other. If this score is adjusted, then a different student is in this situation. I understand and empathize with these students, but there is no reason for a student to expect or seek immunity from this reality.

Second, the student’s question implies that grades are arbitrarily assigned. While I often make mistakes that have to be corrected, I employ a deliberate, thoughtful, and transparent method to determining the grades.

Furthermore, I like to adjust the cutoff between grade to a large, natural break between student scores. As class size increases so does score density, so the probability of finding such a break decreases. Consequently, in large classes the highest score for a particular grade can be fractional percentage points below the cutoff. For obvious reasons this makes it doubly hard to swallow the lower grade.