WEBVTT

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In this session, we will discuss about support washing vector machines.

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Support vector machines.

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Ah, one of the most popular supervised machine learning algorithms.

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And it is used for classification as well as aggression problems, but usually it is used for the classification

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problems.

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The goal of the support vector machine algorithm is to create the best line or decision boundary that

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can segregate the dimensional space into classes.

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So we will be creating several lines between these two classes so that we are able to segregate them

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into different classes.

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Now, these lines will be helpful, as we can easily put the new data in the correct category using

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these lines of segregation and this decision boundary, this line which we have created is called hyperbole.

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Now, because this is just a day data, so this is a lie, but when it becomes a multiple dimensional

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data, because we will be having a lot of features which we will be dealing with.

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So in that case, it will become a hyperbole because it will be not multi-dimensional space.

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Now, for SVM, we choose the extreme point or vectors that help in creating the hyperbole.

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Now, these extreme cases are called support vectors.

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So if we choose in these two classes, so for these two classes, the two points which are nearest to

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this particular class on this and this particular triangle, and the two point from this class which

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are nearest to the triangle class are this and this point.

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So from these points, which are nearest to the other class, these are called support victims.

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So these two points will be known as support weapons for each class.

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And hence, that is where this algorithm is called support vector machines, because it is using these

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support vectors to actually create this line or type of plane.

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So let us see what are different shapes which we have.

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So the system can be in linear form also or in non-linear formula.

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So now let's have a look at this particular data.

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So here we have this data, which is present in a circular form, so I cannot really draw a single line

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here to divide these data points into two different classes.

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So what I will have to do is I will have to transform this data from two dimensional to three dimensions.

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So when I have a look at this data into another dimension, which is I which I have, I did so here

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I have added a dimension Z.

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So when I look at this data with respect to, say, the next dimension, I can see that there is one

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line of separation between both of the classes.

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So I will play I will place a hybrid plane between both of these dimensions and that type of plane will

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actually help us to create a line of segregation between the.

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So here you can see that on transforming back to the spy plane, the leanness apparatus has become a

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circle and hence it was able to segregate the classes.

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Now, let us have a look at these SBM, so what SVM does is it finds the most similar examples between

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the classes.

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So these examples will be the support this, so when we're looking at this particular class, which

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is the mango class, it tries to find out an apple, which is more like and mango.

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So mangoes are usually yellow and longer in size, oval in size.

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So we look for an apple, which is a little bit a little yellowish in color and a little longer than

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usual, or apples.

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So those become the support, therefore, the apples.

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Then when they look at the apple does.

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They tried to find out the which just a little shorter in height, not really oval, but circular in

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shape, and they found them as these support victims.

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Now, between these support vectors, we draw the line, these support vectors actually connected to

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the line of segregation, and between these two lines, we create one line, which is having the maximum

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margin from these two lines.

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And this margin is actually called this line, which we have created is actually called the Hyper.

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So here's the same thing has been explained, that, for example, in Mango's example, other Al Gore

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will try to find the differences between Mango's and that is Mingo's elliptical and yellow by police

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around Andric.

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But SBM will actually try to find out Manguel.

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That looks like an apple that is written down, an apple that actually looks like mineable, which is

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yellow and elliptical, and then use these as the support windows.

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Now, here you can visualize the same thing.

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So we have this red glass and here we have the blue glass.

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So we have found the ones which are nearest to the blue one and all of them are supposed to make those.

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And here the blue ones, which are nearer to the right are the subject victims from the blue glass and

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from them, we have found out the maximum margin and maximizing the margin on both the directions we

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create of.

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Separating hyperbole now, once we have decided upon these supposed victories, we don't really need

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the other points from this data.

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Now, because we don't really need these other points from the data, so we don't really need to compare

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the other points while classifying world.

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All we need is this hyper plane, once this hyper plane has been generated, whatever point we are looking

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at, we will just compare the point with the hyperbole and the direction in which the point lies from

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the hydroplaned and decide what class it belongs to.

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Now, let us look at the steps so we select in case we have a data, then we select all hyper planes

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with separate the data with no points between them.

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That is the red line.

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This these lines.

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These red lines, which do not have any data in between.

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So we create these two hyperlinked.

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Now we maximise their distance, that is the margin between them is maximized once we have maximized

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these distances, then the average line that is the line between both of those two red lines will be

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the decision boundary.

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The line in between the green line is called the decision boundary.

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We could have had multiple lines in between like the line or line B, but because it has the maximum

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distance from both line and B, hence we use the line E as the hyper.
