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When was the last time you ran an experiment?

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Seriously -- I'd like you to
think about it for a minute.

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Pause the video and maybe
even write down a few notes.

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OK we're back.

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Running experiments is really
important, we do it all the time.

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Whether we are making food, trying to find the
fastest bus, or the shortest distance on a map.

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We also run experiments on our family
and friends; we learn very quickly

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as children what makes our
parents happy or upset.

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We run experiments on our partners, our
spouses, and maybe even with our colleagues

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at work.In fact, the only way to
learn anything about a system is

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to disturb it and then observe it.

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I tell my students : "if you stop
experimenting, you've given up on life!"

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and I really believe that.

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I'm Kevin Dunn, from McMaster
University in Hamilton, Canada.

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I work in the Chemical Engineering
department, but this course is not going

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to be about Chemical Engineering.

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My goal is to make the next 5
modules you are about to learn,

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the most interesting course you
will be able to take online.

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This one is going to be memorable and useful.

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I am going to teach you skills that
you can use anywhere in your life -

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and you don't need a University
degree to learn them.

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This course is about running experiments
efficiently.What do I mean by that?

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Efficiency is doing the least amount of work
and getting the most amount of information.

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For those of you that work in companies,

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you know that you almost never get
a chance to do experiments at work.

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So when you get that chance, you have to make
sure that you get it right the first time.

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Now lets take a look at some examples.

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The small things in life matter.

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Let's take a look at boiling water;
something we have all done before.

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The aim with this experiment is to find the
setting that uses the lowest total energy.

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And because energy equals dollars, we want
to reduce energy consumed as far as possible.

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For our experiment, we have two
pots: a glass pot and a metal pot.

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We have electrical heat which we can
adjust to a low, or high setting.

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We can use the lid or leave the pot open.

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So we have several combinations
now, and I'm sure you can guess

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which combination will use
the lowest amount of energy.

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We kind of have that intuitive
understanding from having boiled water before.

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Here's a quiz however that shows
the different combinations.

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Take a look at the options for a minute,

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and pick the setting you think
will have the lowest total energy.

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We are going to come back to
this example in a future class

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and take a look at some actual numbers.

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But if you have the tools, how about trying
that experiment yourself before the next time?

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Something many of us have also
tried before is growing plants.

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There are many things you can change.

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For example: how much water do
you feed the plant each day?

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what is the best time to give the
plant water: morning or evening?

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which type of plant pot should you use
(ones with holes or no holes at the bottom)?

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what happens if you put a plastic cover

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over the plant (to simulate a
greenhouse) or leave it open?

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what is the effect of fertilizer
or no fertilizer?

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Now there are too many combinations

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and we are not sure what the best one will
be unless we do the experiments to test them.

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Another example is a car's gas mileage;
some people call it fuel efficiency.

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The gas mileage is a number that tells you
how far you can drive your car on one liter

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of gas (or petrol, as some
of you might call it).

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To improve fuel efficiency you
might consider the following:

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should you drive with the
windows open or closed?

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does the air-conditioner have a really
strong effect on the gas mileage?

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what about tire pressure: by how
much does it affect fuel efficiency

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if the tires are not fully pumped up?

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can we spend more money and buy
petrol that has a high octane rating;

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is that going to be worth the extra cost?

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and you might also consider how gas mileage
decrease if there are people in the car.

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Once again, we may have a good idea of how each
one of these factors affects the gas milage,

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but what about the combinations of them?

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For example: you can have fully pumped tires,

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but what happens if you load
the car with many people then?

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Google, and other web-based companies are
trying experiments on us all the time.

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Go to this page for an example, and take a
look at Google's experiment on YouTube in 2009.

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In this experiment they were considering
the layout and colour of the page.

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There were 1024 combinations that they tested.

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And the most successful setting increased
the number of user sign-ups by nearly 16%.

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The best combination could
not have easily been guessed,

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or found efficiently by trial and error.

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One of the students I teach in my class at
McMaster recently tried optimizing the strength

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of a concrete cladding that
can be used on buildings.

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He tested several factors: the ratio of of
water:cement; adding plant or cellulose fibres

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to the concrete; if adding steel mesh to see

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if that improved the strength;
and a few other factors.

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These initial experiments
helped him eliminate factors

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that were not influencing
the concrete's strength,

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and then left him with only a
few factors that really mattered.

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He confirmed his predictions that adding
plant material reduced the concrete strength,

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but after his experiments
he had a quantitative idea

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of how just much it reduced
concrete strength, not just a guess.

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Companies are experimenting with all
sorts of ways to improving their concrete.

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Here's an interesting example of a company
that's now adding recycled construction waste

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and old building materials
into their new concrete.

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One common theme in all these examples is that
they have two features: there is an objective

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to improve something, and there are two or more
factors we can change to make that improvement.

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So there's an outcome we want to
improve, and there are factors.

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We'll learn more about these
terms in the next video.

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So I have just given you
several examples to consider.

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What I'd like you to do now, is to take
some time, and think of your own experiment

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that you can work on during the
time that you take this course.

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Write out the topic, and consider how
you can use that to improve your life.

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Consider a topic that can
improve your community;

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or a topic that you can even use at work.

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Even better, I'd like you to
perhaps make a short video about it,

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upload the video to YouTube, and share
the link on the forums, over here.

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Describe your idea with all
of us in this course.

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I'm going to remind you about that again.

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But for now, please get started
with the next video.