### Using Excel: Descriptive Statistics

```Using EXCEL 2010:
Descriptive Statistics
Department of Operations
1
Installing Data Analysis
 To do statistics in Excel, first install the Data Analysis Toolpak
 For a Mac, go to the following web site to download and install
StatPlus LE: www.analystsoft.com/en/products/statplusmacle/
 For a PC, use the following instructions:
 Click the File button on the left corner.
2
Installing Data Analysis (Cont.)
 Then you will see the following menu. Click on Options.
Click
3
Installing Data Analysis (Cont.)
 In the Excel Options dialog, click on Add-Ins.
Click
4
Installing Data Analysis Cont.)
 Then you will see the following window.
 There is a Manage section at the bottom. Click on Go.
Click
5
Installing Data Analysis (Cont.)
 Then click on OK.
Click
6
Installing Data Analysis (Cont.)
 It will take some time to load the package.
 When finished, click on the Data tab in the main menu.
 You should see the Data Analysis module on right.
7
The Frequency Table
 Open the file SoftDrink.xls to create the frequency table.
8
The Frequency Table (Cont.)
 Note: In this example, the data is given in TEXT form.
 The frequency table needs to be created manually.
 Type the titles “Item” and “Frequency” in the columns you want
for the frequency table.
9
The Frequency Table (Cont.)
 Manually type all values in the “Item” column. Be sure not to
miss.
Coke Classic
Diet Coke
Pepsi-Cola
Dr. Pepper
Sprite
10
The Frequency Table (Cont.)
 The function COUNTIF is used here to calculate the
frequencies.
 This function needs two values: the range and the criteria.
 Range is the range of cells with the values you want to count.
 Criteria describes which values in that range are to be counted.
11
The Frequency Table (Cont.)
 In cell D2 type “=COUNTIF(”
 Then select the data range. (A2:A51, in this example.)
12
The Frequency Table (Cont.)
 Type a “,”
 For the criteria, simply select the cell in the “Item” column whose
whose values you want to count. (C2, for example)
 Press Enter to perform the function in this cell
13
The Frequency Table (Cont.)
 Type (or copy) the same function for the rest of the items.
 You will get the following frequency table.
=COUNTIF(A\$2:A\$51,C3)
=COUNTIF(A\$2:A\$51,C2)
=COUNTIF(A\$2:A\$51,C4)
=COUNTIF(A\$2:A\$51,C6)
=COUNTIF(A\$2:A\$51,C5)
14
The Bar Graph for SoftDrink.xls
 Based on the frequency table you just created, you can get the
bar graph.
 Note: You CANNOT create the bar graph using the sample data
directly.
 How to create the bar graph for the following data is shown on
the next slide.
Item
Coke Classic
Frequency
19
Diet Coke
8
Pepsi-Cola
13
Dr. Pepper
5
Sprite
5
15
The Bar Graph (Cont.)
 First select the data in the frequency table. (C2:D6, in this
example.)
16
The Bar Graph (Cont.)
Then click “Bar”.
Then click “Clustered
Bar”.
17
The Bar Graph (Cont.)
 Then you will see the following bar graph.
18
The Bar Graph (Cont.)
The column option in
Excel creates a vertical
bar graph.
Then click “Bar”.
Then click “Clustered
Bar”.
19
The Bar Graph (Cont.)
 Then you will see the following bar graph.
20
The Pie Chart for SoftDrink.xls
 Creating a pie chart is similar to the bar graph.
 Note: You CANNOT create the bar graph using the sample data
directly.
 How to create the pie chart for the following data is shown on
the next slide.
Item
Coke Classic
Frequency
19
Diet Coke
8
Pepsi-Cola
13
Dr. Pepper
5
Sprite
5
21
The Pie Chart (Cont.)
 First select the data in the frequency table. (C2:D6, in this
example.)
22
The Pie Chart (Cont.)
Click the “Insert” tab in Menu.
Then click “Pie”.
Then click “Pie”.
23
The Pie Chart (Cont.)
 Then you will see the following pie chart.
24
The Pie Chart (Cont.)
Click the pie chart to active Chart Tools.
Click
To show the percentages, change
the layout, as follows.
Click “Chart Tools” tab in Menu.
Then click “Quick Layout”.
Then click “Layout 1”.
25
The Pie Chart (Cont.)
 Then you will see the following pie chart.
26
The Histogram
 Open the file Audit.xls.
Then click “Data Analysis”.
27
The Histogram (Cont.)
 In the Data Analysis menu, select Histogram.
 Then click on OK
28
The Histogram (Cont.)
 You will see the Histogram menu.
 In the input section, select the range with your data in the Input
Range. (A2:A21, in this example.)
 Then in the output section, select the cell where you want to
save the result. [Here, the result is put in the same worksheet.]
 Select Chart Output.
 Then click on OK
29
The Histogram (Cont.)
 You will see the following histogram.
30
The Histogram (Cont.)
 In the histogram menu, the bin range was left blank.
 However, you can create your own bin ranges, as follows.
 Type in the bin range first. In this example, the bin ranges are
set to the following (< 10, 10 – 15, 15 – 20, and so on).
31
The Histogram (Cont.)
 In the input section of the histogram menu, enter the bin range
you just created. (B2:B7, in this example.)
 All other settings are the same as before.
32
The Histogram (Cont.)
 You will see the following histogram.
33
Arithmetic Mean for Salary.xls
 AVERAGE(number1, [number2], ...) computes the average
(arithmetic mean) of the numbers.
 Number1 is the first number, cell reference, or range for which
you want the average.
=AVERAGE(B2:B13)
34
Median for Salary.xls
 MEDIAN(number1, [number2], ...) computes the median of the
numbers.
 Number1 is the first number, cell reference, or range for which
you want the average.
=MEDIAN(B2:B13)
35
Percentiles for Salary.xls
 PERCENTILE.INC(array,k) computes the k-th percentile of
values in a range.
 Array is the array or range of data. K is the percentile value.
=PERCENTILE.INC(B2:B13,0.25)
=PERCENTILE.INC(B2:B13,0.5)
=PERCENTILE.INC(B2:B13,0.75)
36
Mode for Salary.xls
 MODE(number1,[number2],...]) computes the mode of the
numbers.
 Number1 is the first number, cell reference, or range for which
you want the average.
=MODE(B2:B13)
37
Variance for Salary.xls
 VAR.P(number1,[number2],...]) calculates the population
variance.
 VAR.S(number1,[number2],...]) calculates the sample
variance.
=VAR.P(B2:B13)
=VAR.S(B2:B13)
38
Standard Deviation for Salary.xls
 STDEV.P(number1,[number2],...]) calculates the population
standard deviation.
 STDEV.S(number1,[number2],...]) calculates the sample
standard deviation.
=STDEV.P(B2:B13)
=STDEV.S(B2:B13)
39
Descriptive Statistics
 Open the file Salary.xls.
Then click “Data Analysis”.
40
Descriptive Statistics (Cont.)
 In the Data Analysis menu, select Descriptive Statistics.
 Then click on OK
41
Descriptive Statistics (Cont.)
 You will see the Descriptive




In the input section, enter
the data range in Input
Range. (B2:B13 here.)
In the output section, enter
the cells where you want to
save the result. [Here the
results are put in the same
worksheet.]
Select Summary Statistics.
Then click on OK
42
Descriptive Statistics (Cont.)
 You will see the following results.
43
Scatter Diagrams
 Open file Stereo.xls.
44
Scatter Diagrams (Cont.)
 First select the data
range consisting of
two columns.
(B3:C12, here.)
 One column contains
values for X and the
other column for Y.
 You can also include
the row with the
column labels.
45
Scatter Diagrams (Cont.)
Click the “Insert” tab in the Menu.
Then click “Scatter”.
Then click “Scatter with Only Markers”.46
Scatter Diagrams (Cont.)
 Then you will see the following scatter diagram.
47
Correlation and Covariance
 COVARIANCE.P(array1,array2) computes the population





covariance XY.
Array1 is the cell range of values for the X variable.
Array2 is the cell range of values for the Y variable.
COVARIANCE.S(array1,array2) computes the simple
covariance SXY.
CORREL(array1,array2) computes the
sample correlation = population correlation.
Open file Stereo.xls as an example (see the next slide).
48
Correlation and Covariance (Cont.)
=COVARIANCE.P(B3:B12,C3:C12)
=COVARIANCE.S(B3:B12,C3:C12)
=CORREL(B3:B12,C3:C12)
49
```