Spreadsheet Concepts

Spreadsheet Concepts

1. Why is computer modelling used?

   • less risky, safer, cheaper
     • no need to test the real object and have something go wrong
   • only need to create one model
     • model can be updated and changed a real life model would need to be created for each alteration
     • saves time and money
   • can be backed up and shared
   • accelerated or slowed down to see effects

2. Modelling

   • of objects
     • cars, rooms, buildings
   • mathematical
     • finance, calculations and spreadsheets

3. Variables

   • identifier associated with particular cell
   • may be a cell reference
   • cell could be named
   • the value contained within variable is used

4. Rules

   • set of procedures that must be followed
   • e.g. validation

5. Formulae

   • the way calculation is presented
   • uses numbers, cell references and math operators

6. Functions

   • represents formula that is too complex
   • uses reserved words
     • IF, COUNTIF, SUM

7. Using spreadsheet for simulations

   • Advantages
     • what-if questions asked without rebuilding model
     • automatic re-calculation
     • graphs produced
     • can be saved/backed up
     • can be shared
     • quick+cheap
     • no specialist training
     • can be edited
     • safer
   • Disadvantages
     • may not accurately represent
     • doesn't factor in real world stuff
     • may miss out variables
       • misleading results
     • may be time consuming
       • may need expensive hardware to run