The Data Grid Overview

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					       The Data Grid Overview
• Covering Objectives and Alternatives
• Formula types
   – Ratings
   – Step Function
   – Increasing or Decreasing Utility Curves
      • Linear, Concave or Convex
   – Direct Entry of Priorities
• Usually no alternatives in ModelView

                                    Retirement Places Rated
           Retirement Places Rated Data Grid

1. One of several
   formulas types
2. The formula
3. The data entered
4. The derived
   priority expressed
   as a bar
5. Covering objective
   The Data Grid Overview continued

• Paired comparisons versus formula types
• Global versus active alternatives
• Extract selected alternatives to the
  ModelView’s Alternative Pane
• Extract to Excel and Import from Excel

                       Retirement Places Rated
        Absolute Measurement
• Compare each alternative with respect to a scale
  (standard) per covering objective rather than
  making pairwise comparisons
• Enter values (data) that are converted to
  priorities via formulas

• You are not making paired comparisons
  (relative measurement)
     Ratings and the Data Grid
• Define Ratings scales for each covering
• Select a Ratings intensity for an alternative
• Learn how to copy a formula

      Ratings Exercise – Small Retirement Placed Rated
   Step Function and the Data Grid

• Define a Step function for a covering
• Enter data for an alternative
  – The data entered is applied to the formula; a step
    intensity is selected and its associated priority is

         Step Exercise – Small Retirement Places Rated
     Copying & Pasting to / from the Data Grid
           using the Clipboard & Excel
1.   From the Data Grid select Edit, Copy All to Clipboard
2.   Start Excel and select Edit, Paste
3.   Select Insert, Name, Define; then enter X as the Name of the
4.   Delete rows A10 through the end
5.   Select Edit, Goto, X defined in step 3
6.   Edit Copy
7.   Return to Expert Choice and select Edit Paste from Clipboard
                  Exercise – Changing the Data Grid
                  Using Retirement Places Rated we will modify what is on the Data Grid.
             Creating and Pasting from a Tab-
              delimited File to the Data Grid
     Use this method when you will be extracting large amounts of data
     from another source.
1.    Export the Data Grid by selecting Edit, Copy to Clipboard. (If need be, first turn off the Ideal alternative.)
2.    Start Excel and select Edit Paste.
3.    Delete the first column of the spreadsheet; this column contains the alternative id.
4.    Delete the Total Column if it has been imported; this is calculated by Expert Choice.
5.    Delete the top two rows of the spreadsheet; these rows contain headings.
6.    Save the spreadsheet by selecting File SaveAs; filename and select Tab Delimited.
7.    Review the contents of your tab delimited file to determine what input will be obtained from other
      sources. For each row you will need an alternative name, cost (if the cost column is present), and a Rating
      or data value per covering objective.
8.    Create a program to extract data from other sources and create a tab delimited file as specified above.
9.    Return to Expert Choice's Data Grid and select Edit, Paste All from a File using the txt file created in step

      Tip: Backup your database before importing a tab delimited file and make a copy of the file imported in Excel in step 2 to
      use as a guide in steps 3 – 7.
   Increasing & Decreasing Utility
      Curves and the Data Grid
• Create either an increasing or decreasing curve
• Enter data
   – The data entered is converted to a priority via the
     utility curve

Increasing and Decreasing Utility Exercise   using previous model
   Entering Priorities in Data Grid
• Entering a priority for an alternative with
  respect to a covering objective

              Exercise - Entering Priorities   using previous model
    Musts and the Data Grid
 Entering must constraints for a covering
                          Exercise   using previous model
    Removing Formulas and/or
    Alternatives in the Data Grid
• How to remove either paired comparisons or
• How to remove alternatives
• Extracting Alternatives to the ModelView’s
  Alternative Pane
                          Exercise   using previous model

• Explanation of the “Needs re-extraction” message
  displayed on the status line…Data Grid or
     Mixed modes in a Model
– Paired comparisons (relative measurement) and,
– Absolute measurement using either Ratings or
  Formula types

– Car example
   • Style is subjective – paired comparisons with respect
     to the alternatives
   • Other objectives such as cost, miles per gallon,
     efficiency of the engine have data values associated
     with them          Demonstration – Mixed Mode Model
      Spanning Global Alternative Sets
• Extract the first group of alternatives from Data Grid and
  pairwise compare them
    – Groups can be based on increasing costs
• Extract the second group and include one alternatives from the
  first group*
• Repeat until all alternatives have been pairwise compared
• Expert Choice 2000 automatically links the priorities of each
  group when calculating the overall result
• To view all priorities in Data Grid, select Totals, Normalize,
                                             Spanning Example
   * If a spanning alternative is not included in each extracted set, you will be asked to link them.

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