STAT/SOC 221
Excel Tutorial
Sam Wang
1
Agenda
• Excel Basics
• Statistics in Excel
• Graphics
2
Excel Basics
3
Excel Cells
Excel Cells are referenced by a column and row
– Columns are indexed by letters
– Rows are indexed by numbers
– Ex: A1 is the top right cell
4
Excel Formulas
Excel formulas consist of–
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“=“ Equal sign
Formula name
“(“ Open Parenthesis
Inputs (will depend on specific formula)
“)” Close Parenthesis
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Example (Product)
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“=“ Equal sign
product
“(“ Open Parenthesis
2,3
“)” Close Parenthesis
Hit Enter. What does it return?
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Calculations
For basic math calculations–
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Start with an “=“
“+/-” for add or subtract
“*” (shift + 8) for multiply
“/” for divide
Excel respects orders of operations (PEMDAS), but Excel
can’t read your mind so make sure you specify what you
want
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Best Practices
To Help you navigate through the spreadsheet–
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Press “shift” to select multiple cells
Press (ctrl + direction arrow) to move to edge of cells
Check your work
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Whenever Excel gives you a number, take a step back and make sure
the number makes sense
Double check your formulas to make sure you’ve inputed everything
correctly
Save Often!!
– (Ctrl+s) is a shortcut for saving
Selecting Cells
– You can select multiple cells by clicking (and continuing to hold down
the mouse button) and dragging your mouse over the cells you want
to select
8
Install Analysis Add-in
Installing the Analysis Add-in will help make histograms
– Analysis Toolpak is not available on Macs, so go to pg 26 instead
– Make sure data analysis add-in is installed
• File > Options > Add-Ins > click Go
• Select Analysis ToolPak and Analysis ToolPak – VBA and click OK
9
Statistics in Excel
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Central Tendencies
The “Average” formula
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Finds the mean of a set of numbers
Formula name - Average
Inputs- The cells you want to find the average of
The “Median” formula
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Finds the median of a set of numbers
Formula name - median
Inputs- The cells you want to find the median of
The “Mode” formula
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Finds the mode of a set of numbers
Formula name - mode
Inputs- The cells you want to find the mode of
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Standard Deviation
The Standard Deviation formula
– Finds the sample standard deviation of a set of numbers
– Formula name – stdev.s
– Inputs- The cells you want to find the standard deviation
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Z-Scores
Excel can also work as a Z-table
– Norm.S.Dist(z-score, TRUE) will return the area to the left
of a z-score
– Norm.s.inv(probability) will return the z-score associated
with an area under the curve
Example:
Find the Z-score and P-value for a sample mean of 15 from a
sample of 25 if the null hypothesis is that the mean is 17 with a
population sd of 4
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Five Number Summary
Useful formulas
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Min and Max find min and max of set of numbers
Large(List of #’s, k) can find the k largest value in list
Be careful about using the quartile function – Not quite the same as
what we’ve done in class
Can also use Excel’s built in Sort function to order the values
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Sample Proportions
Useful formulas
– Countif(array, condition) will count the number of cells in
the array that satisfy the condition
– Conditions might be “>0”, “<0”
– Countifs(array1, condition1, array2, condition2….) allows
for multiple conditions
– Averageif(range, condition, averageArray) will find the
average of the cells in averageArray which correspond to
cells in range which satisfy the condition
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Graphics in Excel
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Bar Graphs
Creating Bar Graphs in Excel
– From the top ribbon go to Insert > Column Chart
– Select the Option in the top left
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Bar Graphs
Creating Bar Graphs in Excel
– Left click in the box that pops up, and select “Select Data”
– Select the Option in the top left
– From the pop-up box, select Add to add data to the graph
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Bar Graphs
Creating Bar Graphs in Excel
– The box the pops up will allow you to specify what data you want to
graph
– The top box is the name you want to give the data. This is the name
that will show up in the legend
– In the Series Values box, click the button on the left and then highlight
the data you want to graph (click and hold your mouse to select the
data. see bottom of slide 8 on how to select multiple cells to capture
all of your data).
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Bar Graphs
Creating Bar Graphs in Excel
– To set the correct X-axis, after you have entered in your data, select
the edit button under Horizontal Category Axis Label
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Bar Graphs
Creating Bar Graphs in Excel
– On the resulting pop-up box, hit the click the red arrow
– then select the bins you have created with your mouse
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Bar Graphs
Modifying your bar graph
– Left click on one of the bars and select “Format Data Series”
– You can change the colors or even decrease the spacing in between
bars
Use Fill to
change the
color of the
bars
Enter 0 to
eliminate
spacing
between bars
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Bar Graphs
Labeling your Graph
– After clicking on your graph, from the top ribbon select Layout
• From there you can modify the Chart Title and add Axis Titles as well
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Histograms
Histograms
– In a new column, define the buckets which we will put observations in
(may be useful to use min and max to make sure you capture all
observations)
– From the top ribbon, select Data > Data Analysis > Histogram
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Histograms
Histograms
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Input Range: Select the Data you want to create a histogram of
Bin Range: Select the buckets which you created earlier
Select Chart Output
Exercise: Think about how you could also use countifs to create the
same output
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Histograms Manually
Analysis ToolPak is unavailable on Macs, so you may need to create a histogram
manually
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In a new column, define the buckets which we will put observations in (may be useful to use min and
max to make sure you capture all observations). These will be the values on the X-axis of your
histogram
Make sure the buckets are sorted smallest to largest
26
Histograms Manually
Analysis ToolPak is unavailable on Macs, so you may need to create a histogram manually
– Use the countifs formula to count the number of observations which belong in each bin
(see slide 15 for a refresher on countifs formula
– In the formulas below, BIN.low refers to the actual number that is the low end of your
bucket, and BIN.high refers to the high end of your bucket. So do not enter in those
words, but replace them with the actual numbers for your bucket (those numbers will
be different for each bucket).
– In the cell to the right of the first bucket type the following•
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=countifs(
Select your data, then enter in a comma
“>=BIN.low” then enter in a comma (include the quotation marks)
Select your data again (should be the same cells as before). Then enter another comma
“<BIN.high” (include the quotation marks)
Then enter the close parenthesis ) and hit enter
– The cell will now show the number of observations greater to or equal to BIN.low (you
need to enter in an actual number) and less than BIN.high (you need to enter in an
actual number)
– Do this for each bucket you have
– Create a column chart out of your data (instructions for column charts start on slide 17)
– See the next slide for an example
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Histograms Manually
BIN.low in this
case is -1
Reference to my
data
BIN.high in this
case is 0
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Questions
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