How to properly conduct an experiment

[Matt Timion]

Experiments must be run in a certain way in order to reduce error. Error is introduced into any experiment as a result of conditions that are different from group to group. What this means that is that we must attempt to keep as many things the same as possible between experimental conditions.

I will explain the rules for participating in experiments, and then give an example.

Before testing a particular method, you must pick a stretch of highway/free which you can travel on uninterupted for a long period of time. If you can travel for 100-120 miles one way, it is better. The reason we pick highways and freeways over city driving is simple. There is too much potential error to be introducted into city driving. For example, if before testing you have all red lights, and after making a modification you have all green lights, it would be unknown if the increased gas mileage is due to the modification you made or due to the fact that you had zero idling time. Traveling on the highway reduces error that can be introduced due to idling, red lights, trains, traffic, etc.

You will first obtain a base measure of your gas mileage. To do this you must fill up your gas tank, travel the strip of highway/freeway and then travel back. You must then fill up immediately. Divid total miles driven by total gallons of gas and that is your gas mileage prior to modification. You then will make the modification to you car (fuel additive, engine contraption, etc) and the make the same trek, using the exact same method. Your new gas mileage will be compared to your old one. Since the only thing that changed was your modification, it can safely be assumed that your modification is the reason for gas mileage increases or decreases.

It is vital that you also maintain the same speed, have the same tire pressure, etc for both trips. Keep as much the same as possible.

Report your results on the thread dedicated to your experiment. When enough people have weighed in their results, statistical analysis will be run and the final report will be written up.

[bagpipe goatee]

< listen to this, matt definitely did his homework with coming up with this. however, with my civic at the gas station i go to, it clicks off at a different place every time, so the more trials the more accurate.

[Matt Timion]

This is one of those elements of error that we really cannot control. That is one of the reasons I want to have five trials per person. This is also why I want everyone to go to the same gas station. While it isn't totally fool proof, doing everything in our power the same way will in fact help reduce error.

If it's off by 1/2 gallon, that's just the way it is. That means it's also off by 1/2 gallon before we do the modification. In the end I think it will all balance out.

Then again one time I was filling up our 87 CRX Si and the stupid pump kept clicking after 3 or 4 seconds. It persisted no matter how much I tried to stop it. In a case like that I'd recommend you go to a different pump.

In all reality, the more trials the better. If you feel up to it, make 10 trips instead of 5.

[bagpipe goatee]

sorry, i missed where you said "five trials." I'm beat and i'm also not feeling the best. don't you just love online complaining?

[bones33]

Matt, thanks for getting this experimentation thing going. Not sure if your are busy (as we all are) or the idea is fading a little, but setting up a database where we all can post our trials and results to including the specific conditions of the experiments would be very useful to us all.

This is just a post to keep the idea alive and a vote for a database we can populate.

[SVOboy]

Haha, you're amazing, he's been spending a lot of time, and he's almost done it, I wouldn't be surprised if it's up in the next day or say, just stick around, ;-)

[Matt Timion]

i've been super busy lately with work. I'm currently working on a mpg database so people can keep track of their gas mileage on the website. I'm also planning on doing an experiment specific database for result posting of experiments.

As the website grows more and more people will use it and it will be a great source of information for future users.

[bones33]

Thanks Matt, it's about time someone accumulated this kind of data so we all can benefit from each other. Kudos!

[Matt Timion]

Originally Posted by beatr911

Thanks Matt, it's about time someone accumulated this kind of data so we all can benefit from each other. Kudos!

I spent a few hours working on the MPG database yesterday. With any luck it will be done today. I will then tackle the experiment database.

[Ted Hart]

Originally Posted by Matt Timion

This is one of those elements of error that we really cannot control. That is one of the reasons I want to have five trials per person. This is also why I want everyone to go to the same gas station. While it isn't totally fool proof, doing everything in our power the same way will in fact help reduce error.

Matt- Kudos on your research procedure! Very well done! There are always improvements (temperature, humidity variations), but %-wise, they're not too large a source of error. Stressing averages is good, too!