Experimental Design B/C

[Phenylethylamine]

NY C States - topic was on paper airplanes. Gave us: several paper clips of varying sizes, eraser head, masking tape (could ask for more), several sheets of different types of paper. However, if the experiment wasn't based on a cargo-carrying plane, one would be ranked below all teams that used the cargo principle. I got hit in the face twice from rogue planes, got 9th.

That's funny. Our regionals topic was paper airplanes.

Paper airplanes are pretty common as a topic, actually, but this cargo-carrying bit was new to me. There was a Nationals event several years back that was paper airplanes (sans cargo); I assume that's what sparked most of the other paper airplane events, since they tend to be pretty similar.

[deezee]

NY C States - topic was on paper airplanes. Gave us: several paper clips of varying sizes, eraser head, masking tape (could ask for more), several sheets of different types of paper. However, if the experiment wasn't based on a cargo-carrying plane, one would be ranked below all teams that used the cargo principle. I got hit in the face twice from rogue planes, got 9th.

That's funny. Our regionals topic was paper airplanes.

what would be the variables in a paper airplane test? the type of paper? what else?

[Slarik]

NY C States - topic was on paper airplanes. Gave us: several paper clips of varying sizes, eraser head, masking tape (could ask for more), several sheets of different types of paper. However, if the experiment wasn't based on a cargo-carrying plane, one would be ranked below all teams that used the cargo principle. I got hit in the face twice from rogue planes, got 9th.

That's funny. Our regionals topic was paper airplanes.

what would be the variables in a paper airplane test? the type of paper? what else?

amount of weight carried, person throwing, design of plane, height launched at... endless possibilities.

[illusionofconfusion]

amount of weight carried, person throwing, design of plane, height launched at... endless possibilities.

We tried design of plane once... It was..bad.
Also, I've noticed that some people have an inclination to do something dealing with wing tips, but I never understood it. What is the point of folding wing tips?

[Slarik]

amount of weight carried, person throwing, design of plane, height launched at... endless possibilities.

We tried design of plane once... It was..bad.

haha. Bad in what way? What specifically were you changing (the entire design, just a piece of it?), and what was your DV? Time in the air? Distance? Accuracy? I'd imagine the procedure of "how to fold" would be a challenge. (although it does sound like fun too)

Also, I've noticed that some people have an inclination to do something dealing with wing tips, but I never understood it. What is the point of folding wing tips?

To me, that sort of falls under "design of plane."

Since folding the wing tips (you mean like elevators, I'm guessing) would increase the drag, and would also tend to pull the nose up, you could have a lot of different DVs (does "point"=dv?). It also depends what you're varying with the wing tips. Size/dimensions of elevator? Degree of "elevation" towards "vertical"? I guess you could manipulate all sorts of things about the wing tips.

[illusionofconfusion]

haha. Bad in what way? What specifically were you changing (the entire design, just a piece of it?), and what was your DV? Time in the air? Distance? Accuracy? I'd imagine the procedure of "how to fold" would be a challenge. (although it does sound like fun too)

Well, we were young and inexperienced then. Between the three of us (this was at a practice, not a real competition), we came up with four completely different plane designs. It was a pretty badly designed experiment, I remember. We were just testing "design" on time aloft. And then we realised that we had to write the procedure on how to fold each and every one of them. We didn't finish. And our coach came in and was like, "What in the world are you guys doing?!"

Since folding the wing tips (you mean like elevators, I'm guessing) would increase the drag, and would also tend to pull the nose up, you could have a lot of different DVs (does "point"=dv?). It also depends what you're varying with the wing tips. Size/dimensions of elevator? Degree of "elevation" towards "vertical"? I guess you could manipulate all sorts of things about the wing tips.

Oh, I see. Well, I've found it easiest to just change the type of paper used, as in copy paper, newspaper, construction paper, etc.

[Phenylethylamine]

amount of weight carried, person throwing, design of plane, height launched at... endless possibilities.

We tried design of plane once... It was..bad.

haha. Bad in what way? What specifically were you changing (the entire design, just a piece of it?), and what was your DV? Time in the air? Distance? Accuracy? I'd imagine the procedure of "how to fold" would be a challenge. (although it does sound like fun too)

Also, I've noticed that some people have an inclination to do something dealing with wing tips, but I never understood it. What is the point of folding wing tips?

To me, that sort of falls under "design of plane."

Since folding the wing tips (you mean like elevators, I'm guessing) would increase the drag, and would also tend to pull the nose up, you could have a lot of different DVs (does "point"=dv?). It also depends what you're varying with the wing tips. Size/dimensions of elevator? Degree of "elevation" towards "vertical"? I guess you could manipulate all sorts of things about the wing tips.

This is a good one: you can have a quantitative IV that is less subjective than release height (which is what we've always done in non-mass-based paper airplane events, because "type of paper" is hard to quantify, for example). I would say that the size of the wing tips (i.e., how far in toward the fuselage the wings are folded) would probably be the clearest variation to use, but as Slarik said, there's a wealth of possible variation there.

DV with paper airplanes tends to be descent time. Distance is difficult to measure consistently because many paper airplanes do not fly straight.

[Slarik]

DV with paper airplanes tends to be descent time. Distance is difficult to measure consistently because many paper airplanes do not fly straight.

Maybe our ED team fails at making and throwing airplanes (after reading this thread, we practiced with airplanes and paper clips) and we found that time was hard to measure -- we just got an average flat line for times, and the times all varied a lot. Anyway, what I'm trying to say is that we found it difficult to measure the descent time too, just bc there are too many factors that go into throwing it (speed, angle).

After doing that experiment with planes, I'm tending to think a good paper airplane experiment (in terms of more measurable would be more along the lines of making a "drop-glider" that flies if you just drop it at say a 45 degree angle (and an IV of the drop height, or number of objects attached to it, or something else). That way you take the throwing variability out of it. Of course, doing it with a person throwing gives you a nice way to write up how you can improve the experiment.

[Phenylethylamine]

DV with paper airplanes tends to be descent time. Distance is difficult to measure consistently because many paper airplanes do not fly straight.

Maybe our ED team fails at making and throwing airplanes (after reading this thread, we practiced with airplanes and paper clips) and we found that time was hard to measure -- we just got an average flat line for times, and the times all varied a lot. Anyway, what I'm trying to say is that we found it difficult to measure the descent time too, just bc there are too many factors that go into throwing it (speed, angle).

After doing that experiment with planes, I'm tending to think a good paper airplane experiment (in terms of more measurable would be more along the lines of making a "drop-glider" that flies if you just drop it at say a 45 degree angle (and an IV of the drop height, or number of objects attached to it, or something else). That way you take the throwing variability out of it.

Yeah, that would really be the only way to make it a "purely" quantitative experiment (which is not to say that there's no variability left; someone dropping a glider may still add some amount of force, which could vary as well, just hopefully less). We've had the same problems with throwing paper airplanes, but it's always worked at least well enough to see a trend of sorts.

Of course, doing it with a person throwing gives you a nice way to write up how you can improve the experiment.

This brings up a good point: sadly, the goal of Experimental Design is not to do good science, but to do a good write-up. It's often to your advantage to intentionally introduce some nice, controlled form of error that you can point to and say, "Look, here's [error] that we could fix by doing [procedure step] differently!"

My parents, both scientists, hate this event, because its short timeframe and rigid rubric encourage data falsification and doing experiments where you know what results to expect – which is not a huge deal in the context of a SciO event, but if you think about it, it's kind of teaching all these young science students that this kind of behavior is okay and actually a good way to get ahead in the sciences.

[deezee]

I guess a problem with multiple trials of paper airplanes will have human error because they can't be folded exactly the same way, but that could go into the errors.