Fluency with Information Technology 7th Edition Chapter 14 Advanced Spreadsheets for Planning

Learning Objectives 1.1 State the two basic design criteria for creating effective spreadsheets 1.2 Explain how conditional formatting of spreadsheet entries applies an interpretation to spreadsheet information 1.3 Explain conditional formulas, and their components and behavior 1.4 Explain the importance of symbolic naming of spreadsheet cells 1.5 Perform “what if” analysis with a spreadsheet 1.6 Use AutoFiltering and advanced filtering to customize spreadsheet lists

1.1 Designing a Spreadsheet To be effective, a spreadsheet must be well designed, informative, and flexible Two basic principles for setting up effective spreadsheets: Focus on form: Make the form logical, the layout clean, and the entries clear and easy to use Explain everything: It should be possible to know what every cell means

Focus on Form Arrange the data logically – for left-to-right readers (like English), this generally means: Descriptive information should be on the top and left sides Summary information should be on the bottom and right sides Use clear and legible fonts Colors should be used in moderation (not distracting) Separate sheet for each table can make working with multiple tables more manageable Hiding information that isn’t needed in the current context can be helpful

Explain Everything Include meaningful column headings and identifying information about the rows Cells and ranges are assigned symbolic names so the content becomes meaningful For summary information cells, choose modifiers like total and largest For computations, include comments to explain assumptions made when creating the formulas

Trip Planning Scenario: Two friends wonder if it’s possible to drive to the Arctic Circle from Chicago. The trip to Fort McPherson is 3,512miles from home and they have learned it will take 67 hours of driving time The given driving time is continuous, which they do not plan to do They decide to use a spreadsheet to figure out how long it will take and how much it will cost

Trip Information: Distances and Times Trip Segment Distance Travel time Chicago, IL to Carrington, ND 778 miles 12 hours, 2 minutes Carrington, ND to Battleford, SK 620 miles 11 hours, 6 minutes Battleford, SK to Fort St. John, BC 648 miles 11 hours, 26 minutes Fort St. John, BC to Watson Lake, YK 555 miles 11 hours, 17 minutes Watson Lake, YK to Dawson, YK 601 miles 11 hours, 55 minutes Round-trip from Watson, TK to Arctic Circle 484 miles 14 hours

Trip Assumptions Additional friends will be included to calculate offset costs The friends are interested in how much the total trip will cost Part of the trip is through the United States, where gas is priced by the gallon in US dollars Part of the trip is through Canada, where petrol is priced by the liter in Canadian dollars

Figure 14.2 Initial Spreadsheet Initial spreadsheet for the Arctic Circle road trip.

Trip Spreadsheet: Applying the Rules Focus on form: The spreadsheet has a title listing the authors and stating the completion date Columns are assigned clear headings The heading row is filled with a soft color that separates it from the content A clear, sans serif font presents the data left-or right- justified in the cells Explain everything: Comments are used: cells with comments have a red triangle in the cell’s upper right corner Hovering the cursor over the cell displays the comment

1.2 Conditional Formatting: Cell Value Is A form lets users specify one or more conditions If the program finds that these conditions apply to the cell, it formats the entry in the manner specified Users specify the condition by picking one of a set of relationships and filling in the limits Example: For the Time Estimate column, conditional formatting makes entries bold if they are above the average travel time

Figure 14.3 Conditional Formatting: Cell Values Arctic Circle road trip spreadsheet with conditional formatting for "long days."

Conditional Formatting: Formula Is Allows for comparison with a cell other than the one being formatted Example: Also bold the Segment value when the trip segment time is above average =IF(B2>AVERAGE(B$2:B$7),TRUE, FALSE)

1.3 Conditional Formulas: Figuring the Amount Paid Make the computation of a cell contingent on the outcome of a condition Example: calculating cost = price * distance/mpg Two choices: express fuel price as a gallon price instead of a liter price express mileage as miles per liter (mpl) Either way, the US and Canada cases have to handled slightly differently =IF(LEFT(D2,2)=“US”, E2*C2/22, E2*C2/5.8

Figure 14.5 Conditional Formatting: Adding Amount Paid Arctic Circle road trip spreadsheet with the Amount Paid column added. Notice that the Time Estimate column has been hidden, and that a comment noting the assumption of 22 mpg has been added to the Amount Paid heading.

Calculating Cost in One Currency Essential to know the expenditures in one currency A Canadian dollar is worth $0.948 in U.S dollars Multiply Canadian dollar values by that number to get US dollars, otherwise leave the value alone =IF(LEFT(D2,2)="CA", F2*0.948, F2)

1.4 Naming: Symbolic Reference Defining names It can be helpful when designing a spreadsheet to give names to components of the sheets A name is a word or phrase assigned to a cell or range of cells Once the name has been assigned, it can be used wherever cell references would be used

Defining and Applying Names Using names reduces the chance of messing up range specifications Errors are minimized when columns and rows are added/deleted Choose Insert > Name > Define ... and enter a name The software assigns the name to that range Choose Insert > Name > Apply to allow use of that name Examples: fuelPrice for the Fuel Price column amtPaid for the Amount Paid column

1.5 "What If" Analysis Because spreadsheets recalculate everything when a number is changed, they are ideal for speculating on the consequences of change Do this directly by changing values, then changing them back You might save the sheet, make changes, and exit without saving Spreadsheets have better support than these methods for what-if analysis

"What If" Analysis: Scenarios A scenario is a tool which can create a named alternative to a spreadsheet based on different inputs A scenario is an aid to understanding changes in plans Example: Changes in gas mileage We create new scenarios using the Add Scenario window, which we can name and archive to run again

"What If" Analysis: Scenario Summary At the bottom of the Scenario Manager window, there is a Summary. . . Button When clicked, a dialog box appears asking what cell we consider the "bottom line" of the computation In other words, if the scenario came to pass, what value are we most interested in If the prediction the software offers is correct, click OK, and you are presented with the Scenario Summary

Figure 14.9 The Scenario Summary The Scenario Summary sheet showing the result of the Tune-Up scenario.

Road Trip Spreadsheet: Example Scenarios The spreadsheet can compute the changed cost of each choice: Having the car tuned up to improve gas mileage Taking along extra passengers to share the expenses Lodging in hotels or hostels versus camping

Analyzing Data Using Filtering Use of the Filtering tool allows access to subsets of information held in a spreadsheet Filtering selects only certain rows from a list It applies only to spreadsheet tables that have column headings Filtering lets users create a customized version of a spreadsheet list that is limited to the rows meeting some criterion

1.6 Using Filters: AutoFilter To use the AutoFilter tool: Select any cell in the list Choose Data > Filter > AutoFilter The result is a redrawn spreadsheet list with triangle menu buttons by each column heading The menu buttons give you options for filtering the list based on data in that column: sorting rows displaying rows containing a limited number of values displaying only those rows matching a specific value in the column

Advanced Filtering The filtering dialog for a column allows various criteria to filter the rows The dialog can also apply multiple criteria combined with AND or OR

Figure 14.14 Advanced Filtering: Distances Over 175 Miles Steps for filtering to keep gas stops for distances over 175 miles: Clicking on the Mi column's auto-filter followed by (a) hovering over "Numerical Filters", (b) hovering over "Greater than…", and (c) filling out the dialog box for the cut-off, to get (d) the result.

Summary Two basic principles underlie the design of effective spreadsheets: (1) focus on form and (2) explain everything Conditional formatting can apply an interpretation to the data in a spreadsheet so that it is easier to perceive Conditional formulas using the IF( ) function allow complex, case-specific data definition and analysis Naming allows the parts of a spreadsheet to be referenced in a convenient and less error-prone way “What if” analysis is a powerful application of spreadsheets allowing alternatives to be assessed Filtering can customize spreadsheet data to particular cases