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### Re: Astronomy C

Posted: February 13th, 2017, 6:58 pm
These two things, to a ridiculous degree.

Like, really, after I'm done with the event this year I'm not going to want to look at another HR diagram for several months or I may rip my eyes out.
You don't like the smooth curves? It's quite a beautiful representation of stars...
I don't like answering repeated questions on what each of the axes is and where to find certain types of stars on the diagram, more accurately. Actual representations of things (i.e. HR for M15) isn't so bad.
Yea, the irregularities on NGC 1846's are pretty awesome.

### Re: Astronomy C

Posted: February 13th, 2017, 7:47 pm
Perhaps you all don't like it, but someone has to make sure we don't have to tiebreak zeros...besides, basics are important!

...hope the studying is going well!

### Re: Astronomy C

Posted: February 14th, 2017, 2:58 am
Perhaps you all don't like it, but someone has to make sure we don't have to tiebreak zeros...besides, basics are important!

...hope the studying is going well!
How would one tiebreak a zero?

### Re: Astronomy C

Posted: February 14th, 2017, 4:58 am
Perhaps you all don't like it, but someone has to make sure we don't have to tiebreak zeros...besides, basics are important!

...hope the studying is going well!
How would one tiebreak a zero?
I would guess the first thing to look at is the open ended/math questions and go one by one and see who was the closest, had the formulas but didn't use them correctly, had the better answer, despite it being incorrect, etc. If there aren't any open ended questions then I'm at a loss. But at that point it's very unlikely for someone to get 0 questions right if they're all multiple choice. In fact, if there are 20 multiple choice questions with 4 options to choose from, then the chance to get all of them wrong is .3% assuming that each one was guessed on randomly.

I hope none of you guys have to get to this point though

### Re: Astronomy C

Posted: February 14th, 2017, 5:03 am
Perhaps you all don't like it, but someone has to make sure we don't have to tiebreak zeros...besides, basics are important!

...hope the studying is going well!
How would one tiebreak a zero?
I would guess the first thing to look at is the open ended/math questions and go one by one and see who was the closest, had the formulas but didn't use them correctly, had the better answer, despite it being incorrect, etc. If there aren't any open ended questions then I'm at a loss. But at that point it's very unlikely for someone to get 0 questions right if they're all multiple choice. In fact, if there are 20 multiple choice questions with 4 options to choose from, then the chance to get all of them wrong is .3% assuming that each one was guessed on randomly.

I hope none of you guys have to get to this point though
After grading some tests earlier this year, I no longer question the ability of people to do really badly.

tbh if someone actually gets zero correct with no partial credit-type stuff to go by, I'd go by number of questions answered, etc. If that doesn't work they'll probably just get marked as P.

### Re: Astronomy C

Posted: February 14th, 2017, 5:15 am
Honestly, if you get a zero it seems like you have bigger problems than tiebreakers

### Re: Astronomy C

Posted: February 14th, 2017, 1:21 pm
Yeah, usually it's been who answered more questions or using open-ended questions (I like using open-ended ones, others like who answered more, some prefer multiple choice...I dislike multiple guess). I haven't actually had to for any, but I've gotten close and tiebreaking has been a major pain sometimes. Some of the tryout tests I made have been so hard I often saw scores of only 1 or 2, and people often tied at a low raw score for the max. Of course, I thought it wasn't so bad...Hard tests are good, but balanced tests are better.

Point is that people may not get 0s, but you don't want the case where it gets really close to that/make a test so impossible it's discouraging and most do badly. Some people may like impossible, so this is why balance is important. As such, you get random easy HR diagram questions, and you will always get those. Alas, at least look forward to getting some points! I do know the complaint for harder questions, though, is normally because of random test writers at regionals copying qs, etc...but doesn't mean some easy standard qs are bad.

### Re: Astronomy C

Posted: February 20th, 2017, 11:16 am
Anyone know where I can find some good radial velocity plot and transit light curve generators for binary systems? I had a good site for exoplanets last year, but it doesn't work as well for stars.

### Re: Astronomy C

Posted: February 20th, 2017, 11:52 am
Anyone know where I can find some good radial velocity plot and transit light curve generators for binary systems? I had a good site for exoplanets last year, but it doesn't work as well for stars.
If you want perfectly circular orbits just graph sine waves with different amplitudes. If you want elliptical orbits, maybe you could just find real light curves of objects that have elliptical orbits

### Re: Astronomy C

Posted: February 20th, 2017, 7:06 pm
Anyone know where I can find some good radial velocity plot and transit light curve generators for binary systems? I had a good site for exoplanets last year, but it doesn't work as well for stars.
If you want perfectly circular orbits just graph sine waves with different amplitudes. If you want elliptical orbits, maybe you could just find real light curves of objects that have elliptical orbits
I'm new to Astro this year, but I learned about those by using google and looking at national tests from the past. One of them has annotated solutions and it is really good, but I can not remember which. If I get to make an SSSSS test next year for Astronomy, I'll be sure to include those types of problems (probably, if the topic allows).