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This assignment is to validate and explore the mathematical model called Fitt's Law. For background on Fitt's law see the Sneiderman text book or wikipedia.

This assignment is to be done in groups of 2 people.

The goal of this assignment is to calculate the constants a and b in Fitt's Law when it is written as:

time = a + b log_2(d/w +1)

• Part 1 : Develop data collection software
  • Generate a software program in order to test Fitts’s Law using two different pointing devices (e.g. mouse, touch pad, trackball, etc.).
  • Choose a programming language based on your own preferences (e.g. Java, JavaScript, Matlab, etc.).
  • Demonstrate the running program and the code in class.
    • Your program does not have to draw graphs
  • Use your software to collect data on user input time during class.
    • Collect 400 data sample for each device
      • 100 for each of four target sizes.
    • Record them as four columns of data
      • (<device>,<time>,<distance>,<width>)

• Part 2: Analyze applicability of Fitts’s Law.
  • Calculate the constants in Fitt's Law according to your data.
    • See this faq for more explanation on this.
    • You can do this by importing the data you collected into an Excel spreadsheet
  • Plot your data on eight graphs
    • For each device and target size ( 8 combinations)
      • Plot Time versus (Distance / Width + 1)
        • Plot the data collected
      • Plot a best fit line
      • Map the parameters of the best fit line y= mx +b to the appropriate constants in Fitt's Law
      • Report what A and B are for each of the 8 combinations
  • Turn in a screen shot of your program
  • Write a one-page summary that interprets the data.
    • Fitt's Law says that A and B should be the same for each device. Are they?
  • • According to you, what are strengths and weaknesses about Fitts’s Law?
    • When does it apply, when should it be altered?
    • What conclusions does your data suggest regarding interface design and Fitt's law?

This assignment will be graded on:

• 50% : are you able to collect data using your program during class time? This will be verified by the instructors in class. We will ask to act as a user and then have you show us the time timing data that you have collected.
• 25%: Quantitative Data Analysis
• 25%: Qualitative Data Analysis

Turn in your qualitative and quantitative analysis in pdf format as one document in a single email with the subject "INF 132 Assignment 02 Fitt's Law" to Harmony our reader at sjiang1@uci.edu