810:025 Computational Modeling and Simulation

Quiz Two Study Guide - Spring 2011 - April 6th


  1. Monte Carlo - given a diagram and graphical setup of an area, be able to determine what the area of below the function or between two functions is by using the Monte Carlo method.

    Know and understand the formula for coming up with a Monte Carlo estimated area when you know the proportion of or the actual count of "darts" that landed inside the area of interest.

  2. Example:  Look at the following diagram which shows a solid point for every dart that was thrown
              and where it hit inside the target area.  The target area is the rectangle there you see
              that goes from x = 1 to x = 3 and from y = 4 to y = 8.
               
              (Note: for practical purposes, only 16 or 20 darts were thrown 
                                                   in the examples shown here).
       
              Calculate what the estimated area of the region above function g 
                                                          and below function h would be?  (The area BETWEEN function g and function h).  
              Please show your work and calculations.
              I need to see your process of arriving at the result.
              You will get partial credit if your equation is correct, but you just had a simple calculation, arithmetic error.
              You will NOT get full credit for just having the correct answer, so show the process for that reason too.
    

  3. In NetLog, show what the output would look like for the following:
  4. What is the output you would see on the NetLogo grid 
    after running the ExampleOne procedure?   
       (Draw a rough picture of about what it would look like). 
             
     TO ExampleOne
         ca
         cro 8
         
         ask turtles [    
             fd 5
        
             pd 
             fd 5
       
             pu
             fd 2
         
             pd
             fd 2
        
             pu 
             fd 2
         ]
     END     
    
  5. Same question as above. Show the output of ExampleTwo procedure.
  6. Show what the screen or the NetLogo grid would probably look like AFTER the following procedure ExampleTwo finishes.
                                    (Note: there may be many possible drawings that get full credit for this
                                            question.   You will NOT be told this on the exam, but you are being
                                            told this for this study guide).  CRO versus CRT - VIP to know!
    TO ExampleTwo
        CA
        CRT 8
        
        ask turtles 
        [
            PD
            FD 8
        ]   
    END
    
  7. Modeling terms and definitions - Vensim Stocks, Flows, Converters, Sources and Sinks, NetLogo Agents, ...
    Fill in the blank with the term, matching, or short answer/definition of the term of user interface element.
  8. Vensim and Andrew Ford homework: 025ModelingTheEnvironment1.html has the magnificent 7 study questions that are due on April 6th.

    The PREFACE to the Andrew Ford book on Systems Dynamics modeling (Vensim approach).

  9. With regard to the world of NetLogo, what is a TORUS setting for the grid of patches? Looking at some output, be able to describe whether the world was a TORUS, or wrapped just horizontally, or if it wrapped just vertically. Recall in class how a sheet of paper could demonstrate a grid world wrapping vertically OR wrapping horizontally, but its hard to show it doing both..
  10. What does the following NetLogo code produce as output?
    to randomColorPatches
       
       ask patches
          [
             ifelse random  100 < 30 
                 [ set pcolor green ]    ;  Note: you might be asked to show the output of a NetLogo procedure that 
                 [ set pcolor white ]    ;        included an ifelse, so be sure to understand how ifelse is used in this example!
          ]
    end
       
  11. Show the output (generally what it would look like). This question tests one of your old assignment questions, the one where the EVEN and the ODD turtles did different things .

    SHOW THE OUTPUT, roughly what it would look like when stagger is done.

  12. to stagger
        ca
        cro 8
        ask turtles [ifelse remainder who 2 = 0  [ fd 5  wait 0.2] 
                                                 [ fd 10 wait 0.2] ]
    end
    
  13. SHOW THE OUTPUT, roughly what it would look like when stagger3 is done.

    Just draw a picture of what the NetLogo window would look like after execution of stagger3 is done.

    Copy and Paste the NetLogo code into your NetLogo if you want to see what the output looks like and verify you figured it out.

  14. to stagger3
       ca
       cro 15
       ask turtles 
           [ ifelse remainder who 3 = 0      
    
                  [ fd 5 wait 0.1]                ; the remainder was 0
    
                  [ ifelse remainder who 3 = 1    ; remainder was NOT 0
                                  
                          [fd 10 wait 0.1]    ; the remainder was = 1
                                 
                          [fd 15 wait 0.1]    ; the remainder was = 2 
                  ]
           ]
    end                        
    

  15. Study Page for Flash bouncing ball model is the ONE NEW ITEM ON FLASH is added here. See the application with the two bouncing balls. RED uses Ease In and Ease Out to be a better model and simulation. GREEN does NOT use any easing in or easing out. Ball moves at a constant speed.

    Example: The Flash bouncing ball with Ease In and Ease Out and without Ease In and Ease Out (not easing). What does the graph look like for EASE IN? For EASE OUT?