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Comment: Re:Conveyor belt problem... (Score 1) 59

Man, that second sentence is awkward. I should have edited.

Suppose that there exists a configuration of N pulleys. To this configuration, we add an additional pulley. The two pulleys that are nearest to this new pulley are separated from the new pulley by a segment of conveyor that runs between two additional pulleys that are (potentially) quite distant. This configuration provides a counter example to the induction suggested above.

Comment: Re:Conveyor belt problem... (Score 1) 59

The paper that they cite is not in English (Abellanas, "Conectando puntos: poligonizaciones y otros problemas relacionados"), so I am not sure that I even really understand what the statement of the problem is. That being said, I don't think that the induction works out the way you want it too. Consider, for example, a situation in which you add a new pulley to an existing configuration and the two nearest neighbors are separated from the pully added by induction by a stretch of conveyor belt that runs between two pulleys that are very far away from the three-pulley configuration under consideration. I don't think that you can actually do the induction on the number of pulleys, as the configuration of the pulleys in addition to the number of pulleys.

Comment: Re:Pedantic Man to the rescue! (Score 2) 580

by the phantom (#46762323) Attached to: How Does Heartbleed Alter the 'Open Source Is Safer' Discussion?

Except that the argument wasn't really "potentially vulnerable to attack" is not the same as "compromised" (though it is certainly easy to see how one could come to that conclusion by ignoring the context---and maybe I am misinterpreting the parent, as well), the argument was that all (but only) SSL sessions using the newer versions of OpenSSL were/are vulnerable (i.e. compromised), and that by virtue of not every server in the world automatically being updated to these newer versions, the statement "every SSL session is compromised" was hyperbole.

One should also note that while the dictionary definition of "compromised" is essentially identical to "vulnerable," there are nuances of meaning in the way in which the two words are used. I would suspect that most people would regard something being "compromised" as more severe than something being "vulnerable." In fact, your example of science fiction seems to make my argument for me. You aren't really disagreeing with the parent, only nitpicking semantics (unless you really do believe that "every SSL session has been compromised," in which case there is a bigger problem with SSL than Heartbleed). If you are going to argue the point (viz: "compromised" and "vulnerable" are synonyms without distinction), why don't you explain what it means to "decimate" something, and how too many people seem to use the word incorrectly.

Comment: Re:Has this changed? (Score 4, Informative) 586

by the phantom (#46747961) Attached to: Jenny McCarthy: "I Am Not Anti-Vaccine'"
The CDC recommended vaccination schedule is easy to find, and contains a "Common Core" of vaccinations (your list, plus a couple more---this is not much, much longer than your list). Of those on the list, the only one that is not obviously part of building herd immunity is the Tetanus vaccine, though given how nasty Tetanus can be to an individual and how effective the vaccine is, it seems like an obvious choice to me.

+ - Skydiver's Helmet Cam Captures a Falling Meteowrong

Submitted by the phantom
the phantom (107624) writes "Last week on Slashdot, we discussed a viral video purporting to show a skydiver nearly being hit by a meteoroid. The video garnered a great deal of critical attention and, after further analysis, it appears that it was just a rock. Steinar Midtskogen, the blogger who originally reported the mysterious object, states

Are we disappointed? The ultimate prize would be a meteorite, but frankly, we had been faced with a mystery for nearly two years, we went public, and thanks to an incredible crowdsourcing effort the mystery was solved beyond reasonable doubt in just a few days. That’s amazing.


Comment: Re:Hand out the PP slides after the talk. (Score 1) 181

by the phantom (#46436151) Attached to: Physics Forum At Fermilab Bans Powerpoint
I actually do something like this all the time in my classes: I will project a grid (either Cartesian or polar!) on the board (either white or black!), and draw graphs onto that grid. I like that much better than using a document projector, since I hate being tied to the lectern---I would much rather have the ability to wander around a bit more.

Comment: Re:Hand out the PP slides after the talk. (Score 5, Funny) 181

by the phantom (#46428155) Attached to: Physics Forum At Fermilab Bans Powerpoint
I generally just yell "Whoooooooooosh!" really loudly as I erase. As for different visual effects, I sometimes use the small eraser, while other times I use the big eraser. I've even used a cloth rag every once in a while. If I'm feeling really snazzy, I'll use two erasers at once (one in each hand!)!

Comment: Re:We give chalk talks. (Score 3) 181

by the phantom (#46428101) Attached to: Physics Forum At Fermilab Bans Powerpoint

One compromise that I like is slides for complicated figures (that would take forever for you to draw, poorly, on the board) and handouts of those slides so that the students don't have to try to recreate them (again, poorly).

Indeed. I would even go so far as to say that this is not a compromise, but the actual, honest-to-goodness, correct use of slides in a presentation, and has been since the dawn of the slide projector. Complicated figures, photographs (of, say, an archaeological excavation or Civil War soldier), or the hypotheses of a theorem that you are planning to prove on the board are reasonable things to put on a slide, and are things that should be put up on the screen for reference. Lacking a projector, handouts are a good alternative (and, perhaps, might be preferable, except for the time that it takes to pass them out and the fact that most of them will end up on the trash).

Comment: Re:Failing as a math teacher (Score 2) 114

by the phantom (#46414211) Attached to: Mathematicians Are Chronically Lost and Confused
That is a good argument in favor of instructors giving time for students to work together in class (though this is often difficult to do in large lecture sections in a university setting, where contact hours are limited), and for students to form study groups outside of class (something that I strongly encourage my students to do whenever possible). I remember a time when the concepts that I am teaching were difficult to understand, but, frankly, that was 15 or 20 years ago, and I have forgotten what I had to do to make it click. I do what I can, but peer interactions are often far more productive than anything I can do.

Comment: Re:Not a random system (Score 1) 264

by the phantom (#46225951) Attached to: Adjusting GPAs: A Statistician's Effort To Tackle Grade Inflation

The material wasn't an issue. I had taken the equivelent of two years of university physics and one year of university calculus in a program from a private university. And, as your incredulity goes, the person in charge of accepting that credit as a transfer, refused to accept the credit and apply it. If I didn't have a math, I couldn't graduate, and I don't remember if science was also required. My senior year of Calculus, I spent no time in my class, until the principal found out, and grounded me to class. After which I brought jigsaw puzzles from home and worked them in the back of the class. After that was discovered by the principal, I was "ordered" to sit at my desk. The room had Pi to 50 digits. I still remember the first 50 digits of Pi. I never scored less than a perfect score on any Calculous test, and slept as much as possible. Near the end of the year, the class was nearing the half-way point of my previous class.

I've been smarter than most of my teachers since about the 2nd grade. The class was told to draw "a man with two orange heads" for a halloween display for an upcoming open house. Everyone in the class drew a man with one head on each shoulder, both orange. I drew a man (normal man) with a jack-o-lantern in each hand - a man, with two orange heads. I was sent to the principal's office and beaten for failure to follow directions (a violation of the law, parents must be notified before any beatings). That's also about when I started getting locked in a closet every day for lunch. That teacher had many accolades, and my mother lied about my address to get me in her class.

With that as my benchmark, I was never worse than my second grade teacher.

As for FERPA, the teacher of record was still the other teacher, and I don't think there was anything in the arrangement that would violate FERPA. The "real" teacher gave the topics, and some minimum mandatory work, and I created a class to fill in the other 90% of the time. I don't know what the grades were derived from, but evaluations of the students were passed to the "real" teacher for her to do with as she wished.

I'm sorry if I wasn't clear, but I accept that you taught a high school class as a high school student. I expressed my concerns about the arrangement, but I accept that you did it.

Having been brought up with standardized tests, I preferred to give them. Doesn't hurt that for IT training, most people were seeking a certification, almost all of which were multiple choice. So it's a common format, with well known rules. It doesn't hurt that it's almost entirely objective (though many times tests will contain poor questions, whether poor wording in the question, or multiple correct answers, of which the "best" is expected, but often hard to determine).

I don't mean to put words in your mouth, but the basic gist of the above seems to be that standardized tests are objective, and this objectivity is an advantage. I agree that standardized, multiple choice tests are about as objective as possible, and that this is a point in their favor. There is one right answer to any given question, assuming that the question is well written. However, as I said way up the thread, such assessments are not very good at measuring anything except rote memorization. I expect my students to be able to do more than memorize the values of trig functions for a subset of angles or the first 50 digits of pi. I want them to be able to analyze and synthesize. Multiple choice questions do a poor job of assessing a student's ability to to this.

Though in college, in smaller classes, the grades were almost divined by the teachers. Twice I feel I did inferior work, but received a passing grade or better because the teacher felt I "tried". I would have felt robbed if it went the other way, but was happy to have the boost the other way. When I got my master's, it was hard to get anything other than an A. That was great. Why? Because it meant that the people learned, without regard to tests, assignments, and such. You got from it what you put in to it. There were no worries about the freeloaders dragging down the group projects, or the annoying people who slow things down asking questions that were answered in the reading they didn't do. Some people are externally motivated, but the internally motivated ones do worse in a graded environment.

I'm not sure of the relevance of this bit. You have repeatedly said that you want to understand my grading scheme. You are exploring the way in which I do things. I don't see how your experience is relevant to that exploration. Can you clarify?

I have been known to remove questions after the fact, usualy with giving the best score from the two scores, so someone who got it right wouldn't get a deduction for it going away. Nobody has ever complained about that. Weights change as well. To help approximate a curve. I'm generous with grades. But not afraid to fail someone that deserves it.

Is there anything that I have said that in any way indicates that my approach is significantly different from the outline you have just provided?

Shortest distance between two jokes = A straight line