A scatter chart takes your data and puts it as dots on a graph and lets you see what the
relationship is. You might want to use scatter chart if you have two sets of data
and you want to see the relationship between the two.You don't want to use it
if you have more than two sets of data. If you have three sets of data that you
should consider a bubble chart. But, if you have two, and you're looking to see
how they affect each other, and look and see what the correlation is other words, scatter
charts could be the right thing for you. So you're looking at a simple one that I
created and, if I move my mouse over it, you can easily manipulate it.
Manipulate it. That sounds weird! I move my mouse over it and I can customize it.
These things never seem to be labeled right, right? So if I want to change the
title just hover over the title, right click, add a title.That easy. If you want
to change the labels. This is the Y axis. You want to change that, hover
over it. Right click. Same thing on the X. If you think there's too much noise in here
one of the easy solutions would be just to make it a little bit bigger but also, if
for some strange reason you think you want to change the size of the dots or
the colors of the dots, just hover over one of them, left click, and you can
control that. Let's make them smaller.
Also, you see that there's a line in here. This line is the mathematical trend
line that it calculated for you and it helps you predict, right? So if you have a Y
value of 33, this line is telling you it is probably going to be about 130 on the
X axis. You can control that trend line and whether or not it's a straight line or an
exponential or a polynomial curve by customizing the graph. So let's look at
how I set these trend line values. I am going to use the little drop down in the upper
right that'll get you to advance edit. Bring up a menu. Stay on the
customization ribbon and these are a lot of the values that we could just set on the
face of the church. It's easier to use your mouse but for some of the more advanced
options you want to be in here. We'll scroll down to the trend line
and we chose a linear one. That's what we're showing right now.
I'll show you what happens if we change it to an exponential. If you harken back to your
calculus days or trigonometry days - I don't member which one. It was a few years
ago.
It tries to fit a curve in there. That correlation is point .492. If you go
back to linear, it was .494. The higher the correlation, the better it
is for your data. If you keep this line as linear, it fits the data a little bit
better. If you want to show the correlation. I have it on right now it's
R squared, you want to have that clicked. That's your correlation. If it's not to a mathematical audience
you might want to leave that out. It would just be distracting. The other thing is that
the other part of the calculation there can be hidden as well.
In between those settings you can get a pretty nice representation
of your data and where it lies. Click update. We went through these setting. I don't think
we really changed anything because we decided we like it the way it is. Alright, let's
kick this party up a notch.
Here's another set of data that doesn't have nearly as much in it and it's not
as pretty of a relationship either. First we'll do a little bit of cleanup
on the chart. So I look at this.
Some of the things that I think are, one, the dots are too small. So I just left
clicked here and I'm going to make them seven pixels. Ha ha, joke's on me. I guess they're already 7
pixels. Let's try 14. OK, to me that looks better so let's do that. I'm just
looking at the chart and I don't see any data underneath. I don't know what this means this.
This one is number of ice cubes, right?Come over to the left hand side where it's empty,
I left click and I'm going to choose to the left vertical axis title.
Ice cubes. So this is how many ice cubes you want in your beverage and as it gets
warmer you want more. To explain that, right click that this is temperature.
There's your two labels.
Ice cubs. I don't know how refreshing that would be. What you're typically doing with
these charges, you're looking for a relationship. Again I think it's nice
to put a line in it so I'm going to left click on one of these dots now.
I'm going to drop-down this trendline box. Let's try and linear. That looks like
it's pretty helpful, right? There's a good correlation there. But just to see,
let's try an exponential because maybe the hotter it gets, you want even more ice. I
think that looks like a little bit tighter let's leave that trend line.
Data one series is pretty robotic sounding so let's go into the advanced edit.
Let's give that a label. So we'll go down to trend line.
We'll just call it the trend. This is super helpful, right? If you're someone who prepares
a water professionally and you want to maximize your time and the amount of ice you use. You can
check the temperature before you decide how many ice cubes before filling each glass of
water. I think I'll probably patent this process. It's pretty complicated. That's a
more simple scatter chart and I just use that to show you an exponential
relationship and having the graph be a bit smaller. Let's look at a
relationship quickly that has a perfect correlation. This correlation would be a value of
one. If I put the value of R2 on here.
The size of your shoes. The left shoe predicts the size of the right shoe.
Almost always does. I'm sure you probably have a second cousin that has two
different sizes of feat but this illustration is pretty good for showing
what perfect correlation is. One to one. Lower left upper right. This is an example of
a negative perfect correlation. Negative one. The amount of heat needed as the
temperature rises will go down.
Hypothetically, it may be a straight line. In the real world, would this be a straight
line? I don't know. But in my little Google sheets example it may be one so that you
could see what a negative one correlation was. The last thing with scattered charts
that I want to show you is doing error bars. The chart that we're looking at
right now has a trend line which is a common way to show the trend but another
way that you can do it may be helpful for whatever you're doing is to show it
as error bars. A lot of the options you can access and change by left clicking here.
You can change trend line that way but you can't do error bars. I'm going to take the
trend line off for now. Left click to remove it. Then we'll have to go to
advance edit again. Stay on the customize tab and we'll go down near the bottom
and you see error bars. Right now we have none. Let's put them on. You can do them
as a constant value or percentage. Let's do constant and keep it easy. These are
way too big.
This doesn't follow the trend at all. I don't think. You're going to want to have
a smaller range so let's just change it from 10 to 2. Looks about right.
Maybe a little bit too big but maybe this is how big your variation. So
this is sending a different message. This is saying your data is probably going to
lie somewhere between these two error bars.It's not saying I'm going to show you the
average and it's most likely gonna be right there. This is more showing you the
distribution of where it could be. If you try to do this on a chart that has too
many dots, you can't see the bars and it just looks like a mess. But if you
don't have very many dots like this chart right here, I think it's a good
option. That's really all the major settings for scatter charts. You can go
in and you can customize all the rest. There are lots of different ways to do it but
these are the major items. I hope that was helpful. Thanks!