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Could someone please elaborate on the "Standard of Comparison"? I have a small idea what it is, but I rarely get it right. Usually we put some kind of zero.

brayden box wrote:Could someone please elaborate on the "Standard of Comparison"? I have a small idea what it is, but I rarely get it right. Usually we put some kind of zero.

Copied and pasted from 2008 training manual found online:

"STANDARD OF COMPARISON or EXPERIMENTAL CONTROL is component or level in which the independent variable is not changed or manipulated. It is used to verify that from trial to trial everything is kept the same and that the change in the independent variable is actually causing the response in the dependent variable. It can help to identify hidden variables which you did not identify as constants and which may affect you results. It may be a level of the independent variable or a separate group which receives not treatment. For the examples listed above you may choose the 0% or 0 cm levels as a standard of comparison because they do not be reflect a change to the independent variable. In testing light exposure on plants, there might be a test group of plants which receive different levels of light and a control group of plants which receive no light."

SPP SciO wrote:

brayden box wrote:Could someone please elaborate on the "Standard of Comparison"? I have a small idea what it is, but I rarely get it right. Usually we put some kind of zero.

Copied and pasted from 2008 training manual found online:

"STANDARD OF COMPARISON or EXPERIMENTAL CONTROL is component or level in which the independent variable is not changed or manipulated. It is used to verify that from trial to trial everything is kept the same and that the change in the independent variable is actually causing the response in the dependent variable. It can help to identify hidden variables which you did not identify as constants and which may affect you results. It may be a level of the independent variable or a separate group which receives not treatment. For the examples listed above you may choose the 0% or 0 cm levels as a standard of comparison because they do not be reflect a change to the independent variable. In testing light exposure on plants, there might be a test group of plants which receive different levels of light and a control group of plants which receive no light."

Sometimes it's simple to figure out what goes in the control group, but more often than not, you can't completely remove whatever the IV is, so I teach my students to seek the most "normal" conditions and use that as a control group. There's not necessarily a single "right" way to set it up for each experiment. For example, one of the first practice Exp. Des. prompts I give my students is to design an experiment concerning the bounce height of several sportballs (they may have a handball, tennis ball, golf ball, and basketball provided). There's a few different ways to go about this -

1. Choose one ball, and drop it from different heights, and record the different bounce heights (IV drop height, DV bounce height). Not necessarily the best - you could set up your "control" as a 0cm "drop" and record 0cm for "bounce height" but what's to be learned from that?
2. Drop all the different sportballs from the same height and record bounce heights (IV type of ball, DV bounce height). May be better - but what's the control group? You could choose any type of ball, but you'd be expected to provide a rationale... "We chose to designate the basketball as the standard of comparison, because they are frequently bounced intentionally by players as they dribble." I'd be happy with that logic, but if they chose another SOC and a different rationale, it may work also.
3. Choose one ball, and drop it onto different surfaces, such as the tile floor, wooden desk, floor covered with cardboard, and measure the bounce height (IV bounce surface, DV bounce height). In this case, you'd select the most normal/typical surface as the control (maybe the wooden desk, if the logic is it's similar to a basketball court?)

Keep in mind, for every decision you make, you need to justify your decision in writing. So, even if the way you designate your control group/SOC seems arbitrary, a thoughtful rationale will earn points.

Full disclosure: I've never actually judged/scored this event at a tournament, so, corrections are welcome if I'm incorrect about anything here

what is the most common test you get? thanks this is my first time doing this event and I'm a bit nervous.

whovian11 wrote:what is the most common test you get? thanks this is my first time doing this event and I'm a bit nervous.

I would expect physics-based labs to be common, since they are generally easier to set up (Disclaimer: I did this event once, four years ago).

Unome wrote:

whovian11 wrote:what is the most common test you get? thanks this is my first time doing this event and I'm a bit nervous.

I would expect physics-based labs to be common, since they are generally easier to set up (Disclaimer: I did this event once, four years ago).

Typically, at a regionals level, you will be a lot of physics experiments (don't worry, they pretty much require 8th grade physics), but sometimes there are very basic chemistry experiments. such as factors affecting solubility of sugar or salt, for example. Nothing should go beyond a high school level.

ScienceOlympian wrote:

Unome wrote:

whovian11 wrote:what is the most common test you get? thanks this is my first time doing this event and I'm a bit nervous.

I would expect physics-based labs to be common, since they are generally easier to set up (Disclaimer: I did this event once, four years ago).

Typically, at a regionals level, you will be a lot of physics experiments (don't worry, they pretty much require 8th grade physics), but sometimes there are very basic chemistry experiments. such as factors affecting solubility of sugar or salt, for example. Nothing should go beyond a high school level.

Agreed. In my 3 years of ExpDes I would say a good 75% of the tests I took were related to basic physics. The other ones were easy chemistry. There was also that awful one at regionals that one time. I still don't really understand what they were looking for.

Thanks!!! I'll definitely study more physics!

This is also my first time doing this event.... I'm pretty nervous on what to expect. We have done a couple of the practice tests and now I'm beginning to wonder if we will end up having to do multiple experiments in the 50 minutes we have, I also feel like all of the experiments we tested with the practice lists were to easy. Can you give me an example of what to expect?