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Okay, so far we've assumed that the only feature relevant to the value of my house,
is the square feet of the house.
But I dig into the data set a little bit more, and
I look at a house that's supposed to be very similar to mine.
It's a house that has very similar square footage.
And so, this house is definitely making an influence on what the predictions are for
my house.
But I look at it and I say, and I look at the specific listing, and
it shows that that house only had one bathroom.
It's actually quite a big house, only one bathroom.
And I say that's really, really not comparable to my house,
which has three bathrooms.
So that the value of that house, that house sales price
really shouldn't be indicative of what my house sales price should be.
So instead what we can think about doing is adding more features.
So instead of just looking at the relationship between square feet and
price, we can add number of bathrooms.
And now for
each one of the listings that I looked at before, I'm gonna have to go through and
record how many square feet that house had, and the number of bathrooms.
And I'm gonna plot each of these points in the 3D space.
Okay? So it's this hyper cube of square
feet versus bathrooms versus price.
And now instead of fitting a line to the data, if I'm thinking about just a very
simple model, I can think about fitting a hyper plane.
Okay, so it's just a slice through the space.
We're here.
This is the equation of the hyper plane, and this is the equation of this plane.
So we have w0, which is our intercept, just where this plane lives up and
down on the y-axis.
And we have w1 times the number of square feet, and
w2 times the number of bathrooms.
But a question is where do we stop?
Do we just want to include the number of bathrooms as our additional feature?
There are lots of things we could think about including.
We could think about in addition to our square feet, number of bathrooms,
there's the number of bedrooms, the lot size, how old the house is, and
the list goes on and on.
In terms of different properties of the house that could be influential in
assessing it's value.
But we're gonna actually hold off on this question of looking at which features
are important for this regression task, until we get to the regression course.
So go to the regression course to learn more about this topic.
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