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Comment Re:Use Class Rank (Score 1) 264

That's the problem with people who think that knowing a subject makes it possible to get every answer correct. Some of the best courses I took had questions on exams that were not possible to answer correctly without access to a supercomputer and a few hundred CPU months, where the instructor was looking for depth of knowledge and technique rather than "the right answer". It makes me wonder if those that advocate for absolute grading have ever had to do anything difficult in their lives. Or ever considered that two exams on exactly the same material could have different difficulties.

It's also not true that scores are proportional to knowledge. An obvious example is the multiple choice, multiple answer test where negative scores are quite possible.

Typically I design upper division exams for an average of 50%. I could easily design for 84% "standard," but it would tell me and my students less, because there would be less distinction at the upper end. It would be more difficult for students to know what they do and don't understand well. Yet you would have me punish my students for making the people with As work a little harder and maybe learn a little more.

Comment GPA isn't the problem, Grades are. (Score 1) 264

The problem is that grades are arbitrary. The instructor defines them, and the universities and the students pressure instructors to give higher grades in lower division courses. Instead of arbitrary grades, assign lower division grades by quintile. Top 20% A, Bottom 20% F. It's enough to maintain student competition, gets rid of the "easy graders". For higher division, drop the lowest grades, with F being giving to a small percentage at the option of the instructor. Mid division would be ABCD quartiles. Upper division ABC. Graduate AB.

If it's possible for a student to get a degree by taking only "easy" courses, that's a problem with the design of the major curriculum.

Comment Re:They should upgrade the warning ... (Score 1) 526

The difference is that the batteries can ignite without an external heat source.

That doesn't necessarily make them more dangerous. I have a friend who lost a home to a fire that started in the engine compartment of a car in the garage. It was probably a leaky fuel line dripping onto a hot engine component. In your reconing is that an internal or an external heat source? Of order half a dozen car fires happen during a typical commute day on SF bay area freeways, and that's not counting the fires that start because of collisions.

It doesn't seem that likely that Teslas are any more fire prone than any other car. The rates for gasoline cars have about one serious (i.e. reported to police) fire per 18 million miles. If the average car goes 180K miles, that's about 1% that go up in flames at some point. The average Tesla hasn't gone that far, and I don't know what the fleet mileage is, but I'll be surprised if they are that flammable.

Comment Re:Science? (Score 1) 440

When I drop a ball, and show that it follows the path predicted by gravitation, what more must I do to "show" that gravity caused the ball to fall.

When the atmospheric CO2 content increases and the global average temperature goes up about the amount Arrhenius said it would back in 1906 due to basic physical principles, and then I show that is in fact human emissions that caused the CO2 increase, what more must I do to "show" that global warming cause the temperature increase.

Comment Re:Honesty? (Score 1, Insightful) 440

Another well named coward that doesn't understand science. Do you know what disproving global warming would get a scientist? Fame and fortune! Oil companies would have a bidding war to hire him. You know why it hasn't been done? Because global warming is real and it's happening at pretty much the rate Arrhenius predicted 107 years ago. The reasons why it is happening should be obvious to anyone who has studied the subject. The way to stop it is also obvious.

The big fame in science comes from disproof. The most referenced papers of mine are ones where I disproved theoretical claims. Every scientist wants to be the one who disproves something big.

Comment Re:Tense About Nuclear Weapons (Score 3, Insightful) 440

The AGW hypothesis may or may not reflect actual reality. That's the problem with an unfalsifiable hypothesis.

The AGW hypothesis is not unfalsifiable. People with no understanding of science often make that claim. A couple decades of significant cooling (0.05C per decade or so compared to the warming trend of 0.18C/decade warming since 1970. ) while CO2 levels continued to climb would probably be enough to do that.

The problem for people who like to lie about science is that the science of AGW is very basic and well understood. To pretend it's not going to happen you have to imagine something that could stop it. And so far nobody has been able to invent something that can stop it short of a catastrophic breakdown in global atmospheric and oceanic circulation. Be my guest. Find something that can prevent CO2 from increasing temperatures and prove it. In 1906, Arhennius calculated the climate sensitivity to a doubling of CO2 when including water vapor feedback was 2.1C. Current estimates are between 2C and 4.5C. Go ahead, find a way to make the climate sensitivity negative and show that it works.

Comment Re:Honesty? (Score 5, Informative) 440

The Intergovernmental Panel on Climate Change (IPCC) was formed in 1988, so where do you get the idea that what it's called has changed?

The indisputable increase in global average temperature due to human CO2 emissions is called global warming. The response of the global climate system to that increase is called climate change. The climate changes vary by locale. That distinction has been there for quite some time.

Comment Re:That's sad. (Score 5, Informative) 312

It's important to distinguish between the SETI Insitute, an organization that does some SETI (but also does a lot of biology, geology, planetary science and bioastronomy), from SETI the discipline. Most people who do SETI do not work at the SETI Institute.

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