Scatter Chart In Excel 2010A scatter chart plots the values for two variables as a set of points on a graph. The independent variable is plotted on the

x-axis and the independent variable is plotted on the y-axis. In a scatter plot the x-axis and y-axis represents the actual

values of the variable. Scatter charts are best understood by looking at examples.

Here is sample data that suggests that there is a relationship between the amount of fuel consumed and the distance

a vehicle can travel.

Open an Excel spreadsheet and type in your X and Y

data points like the example to your left. It’s hard to

see what’s going on when we look at raw numbers, so in

order to find a relationship between the two variables we

use the data to create a scatter chart.

Select/highlight all the cells that contain data and

then…

Click Insert > Scatter, and choose one of the scatter charts. We

chose “Scatter with only Markers.”

The scatter diagram, even in its current state shows us that there is a

possible relationship between fuel consumption and distance travelled. Here

is the scatter chart we created. You can see that as more fuel is consumed,

the distance travelled becomes greater.

But we can make this relationship even clearer by using trendlines.

Using Trendlines In Scatter Charts

Trendlines mark out the trend in the data. To display a trendline in our scatter

chart, click Chart Tools > Layout > Analysis > Trendline.

In the Trendline panel that opens, “Linear Trendline” is probably our best option,

so choose that.

Table 1: Fuel Consumption and Distance Travelled per Day

Fuel (L) Distance (km)24 32013 24029 51519 29021 30535 45010 19540 58044 64518 255

Adding a trendline to a scatter chart is a good way of visually representing the

underlying trend in the data.

This trendline helps us understand the data better, but we can add more useful

information. The trendline represents a linear equation (remember that we chose linear

trendline) and we can see that equation displayed on the chart.

With the chart selected, click on the Trendline button again (Chart

Tools > Layout > Trendline > More Trendline Options).

The Format Trendline window that opens is pretty big, but there’s only one

option we need here: “Display Equation on Chart.” Ensure that there is a

check in that checkbox and click close. You will then see a linear equation

of the form

y = mx + c

A bit like this:

From the equation, the value of “m” is the slope of your line.

When you know that the X-Y intercept is zero then you can have your trendline passing through zero. To do that you make sure that the set intercept has a check in the checkbox and the intercept is set to 0.0. Click close.Now you have the equation for the line passing through the origin (0,0)

You can move the equation to any area of the graph you wish.

Adding a title to your graph:

With the chart selected, click on the Chart Title button (Chart Tools > Layout > Chart Title > Above Chart Options) and type in your title. The title of a

table is always the dependent variable Vs the independent variable.In this example Distance travelled Vs Fuel consumption.

Adding The X-axis Title:

With the chart selected, click on the Axis Title button (Chart Tools > Layout > Axis Title > Primary Horizontal Axis

Title > Title below axis Option) and type in your tittle including the unit.

Adding the Y-axis Title:

With the chart selected, click on the Axis Title button (Chart Tools > Layout > Axis Title > Primary Vertical Axis Title > Rotate Title Option) and type in your title including the unit.

Hurray!!! You have just made a graph in Excel!

Homework:1. With the time remaining in class, please start a new Excel graphing exercise, using the steps provided here,

to make a graph of your Burning Candle Lab data!!! You must have data for all three beaker sizes represented on the same graph!

2. Copy and Paste (DO NOT CUT OUT AND GLUE) your Excel graph into your Candle Lab Report document. You will need to add an “Analysis” section to your report. This is where your graph goes. The Analysis section belongs between the Observation and Discussion sections.