Introduction to Spreadsheets
Bent Thomsen
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What is an electronic spreadsheet?
It is the electronic equivalent of an accounting
worksheet, comprised of rows and columns to
allow you to do many tasks in the
organization of numbers in a clear, easy to
understand format
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What is an electronic spreadsheet?
• It is a tool to help you calculate budgets, do
economic analysis, statistics, planning,
engineering calculations, …
• Replaces pen, paper and pocket calculator
• Can show diagrams and graphs
• Can input data from other programs
• Can output data to other programs
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Some Advantages of Spreadsheets
• Spreadsheets are capable of exploring “whatif”scenarios (e.g. budgets, submitting bids)
• Once it is set up properly, the user can save
time by never having to set up the spreadsheet
again
– Blank spreadsheets are called templates.
– Monthly salaries,grade sheets
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Spreadsheet terminology
• Row - horizontal axis (designated by numbers)
• Column - vertical axis (designated by letters)
• Cell - intersection of row and column (designated
by an address comprised of the column letter and
row number e.g. A1)
• Block//Range - a rectangular group of one or
more cells (identified by block coordinates (e.g.
A1:G4)
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Spreadsheet terminology (con’t.)
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•
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Label - alphanumeric
Value - a number or formula result
Formula - creates relationships among other cells
Template - a notebook that has labels, formulas,
and all of the formatting but no actual data (e.g.
actual figures and numbers)
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How big is a spreadsheet?
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Normally you see 9 columns and 18 rows
= 162 cells
One sheet has 256 columns and 65536 rows
= 1677216 cells
That is more than 103000 screens
Would take 34000 A4 pages to print
Take 194 days to fill at one cell pr second
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Exploring the Excel Screen
Title bar
Menu toolbar
Standard toolbar
Formatting toolbar
Screen Tip
Active worksheet in
workbook window
Task Pane: organizes
related commands
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Activating Toolbars
Click on View
and Toolbars
Toolbars submenu appears
Click on desired toolbar
Check indicates active
item; click to
deactivate
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Moving Around the Worksheet
Working in an active cell
(intersection of a row
and column)
Insertion point:
where text will
be entered
I-beam: to
place insertion
point
Cell pointer
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Moving Around the Worksheet
• Move cell
pointer
– arrow keys
– scroll bars
• Change pages
– click on tabs
– tab scroll
buttons
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Moving Around the Worksheet
• Consider cell B4 active
• Note
– thick cross mouse pointer
– row, column buttons highlighted
• After scrolling to right, note …
– row button still highlighted
– name box still shows B4 as active cell
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Moving Around the Worksheet
To select a column
•Click on the column
heading button
•Whole column is
highlighted
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Entering Labels
• Click desired cell to make it active
• Label is displayed both in cell and in formula bar as you type
• Label displays out of its column
– as long as other columns are empty
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Worksheet with Labels
• Note
– Documentation
section
– Label cut off, next cell
occupied
– Labels aligned left
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Editing a Cell's Information
• Click on desired cell
– Cell pointer moves there
– Contents displayed in
formula bar
I
• Click mouse pointer
(I-beam) to location
within text
– type, delete, copy, paste
as needed
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Entering Values
• When entering numbers
– do not use commas
– numbers are right justified by default
• To proceed to next cell right use [Tab] or right
arrow key
• To proceed down, use [Enter] key
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Entering Formulas
• Formulas are mathematical equations
– perform calculations
– always start with an equal sign (=)
...
• Formula shows in
formula bar
• Note color references
in formula
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Entering Formulas
• After formula entered and cell pointer
moved
– Formula does not show in formula bar
– Result of calculations
shows in cell where
formula entered
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Operators
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•
•
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^ - exponents
+ - addition
* - multiplication
/ - division
- - subtraction
= - function
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Order Calculations are Performed
• First exponents
• Then any multiplication and division in the
order they occur
• Then any addition and subtraction in the
order they occur
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Parentheses
• Operations within parentheses are performed
before those outside.
• Within the parentheses the basic rules are
followed.
• Multiple sets of parentheses, the innermost are
executed first followed by the next set.
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Built-in functions
• Functions are pre-written formulas
• Functions must start with an equal sign
• Functions takes value(s), perform an operation,
and returns a value(s)
• Values you use with a function are arguments
• =AVERAGE(D3:D7)
– AVERAGE is the function
– D3:D7 is the argument
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Using Functions
• Advantages of predefined functions
– save time
– more accurate
• Using AutoSum
– Click cell at
bottom of
column
– Click AutoSum
button
– Excel assumes
it should total
the column
– SUM function
inserted
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Using Functions
• AutoSum can also be used to right of a row
of numbers
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Using Functions
• Note end results of
using AutoSum
• Note:
– Click AutoSum
button once to
display formula,
again to apply
– SUM formula
displays in
Formula bar
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Using the Function Insert Feature
• Click on Insert, and Function
• Insert Function dialog box appears
Select function
category
Choose specific
function desired
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Using the Function Insert Feature
Arguments of
function must be
specified
Animated border
shows selected
range
Note calculated result
of inserted function
Formula
appears in cell
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Using the Function Insert Feature
Note calculated result
of inserted function
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Creating a Chart
• Select series of
numbers from
worksheet
• Click Chart Wizard
button
– Dialog box opens
• Choose chart
type, sub-type
– Note preview
button
Click on Next
button to proceed
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Creating a Chart
• Step 2
– Review and change
series range as
needed
– Click CategoryLabels
button to specify
source of labels
for chart
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Creating a Chart
• Labels now show in
legend
• Range for labels
now displayed
Click on Next
button to proceed
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Creating a Chart
• Step 3
– Enter titles (which
will show on preview)
– Specify legend details
on legend tab
– Specify Data Label
details as shown
Click on Next
button to proceed
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Creating a Chart
• Step 4
– Specify where chart will appear
– Click Finish
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Creating a Chart
• Chart is displayed as object in worksheet
Note Chart toolbar
displayed while chart
is selected
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Statistical analysis in Excel
• you can do a range of statistics in Excel using
the ‘Analysis ToolPak’
• you can calculate a correlation matrix and
undertaking regression analysis
• results of this analysis goes on additional sheets
in the Excel workbook. remember to save this
workbook often (as a .xls format file)
• note, Excel is powerful but it is not a statistics
package. Alternatives are SPSS and Minitab
which are full function statistics packages and
will do lots more. they will read Excel
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spreadsheets and dbf format data files
Opening the ToolPak, Excel’s
data analysis add-in
go to ‘Tools’ -> ‘Add-Ins’
choose ‘Analysis ToolPak’
and click ‘OK’
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Correlation analysis
• are A and B related?
• correlation coefficient provides a single numerical
value describing a linear relationship, telling us the
direction and strength
Percentage Limiting Long Term Illness against Percentage No Car
50
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Percentage Limiting Long Term Illness
40
35
30
25
20
15
10
5
0
0
10
20
30
40
50
Percentage No Car
60
70
80
90
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• you can get Excel to add
the ‘best fit’ line (Trendline)
through the scatter of points
• to do this select the data points
on the chart, right-click and
choose ‘Add Trendline’
• In the ‘Add Trendline’ box
choose ‘Type’ - ‘Linear’ and
click ‘OK’
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Percentage Limiting Long Term Illness against Percentage No Car
50
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Percentage Limiting Long Term Illness
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What do you think r will be??
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30
25
20
15
10
5
0
0
10
20
30
40
50
60
70
80
90
Percentage No Car
• now we want to calculate the actual Pearson’s correlation
coefficient (the r value) for this relationship
• it is very easy to calculate with Excel
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• go back to the ‘Tools’
menu and select ‘Data Analysis’
In the ‘Data Analysis’
window choose
‘Correlation’
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Correlation analysis
• this window allows you to
define the variables you want
to correlate
• you will correlate all your
census variables to get a full
correlation matrix
• the ‘Input Range:’ box defines the columns in the spreadsheet
you want to run the correlation on. click in this box and then
with the mouse select all the columns of census data
•check the ‘Labels in First Row’ box as well. make sure the
‘New Worksheet Ply:’ option is checked and call it ‘correlation’
and then click on ‘OK’
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Steps in Developing a Spreadsheet
1.Determining the purpose - what inputs, what
outputs, what printed reports
2.Planning - plan it on paper first
3.Building and testing - make sure it manipulates
the data correctly
4.Documenting - should include something within
the worksheet itself (directions, name and date)
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