Introduction

This lab will help you practice all the Matlab commands needed to complete project 2 described on page 16 of the course supplement. Note that there are other components of the project that do not require the use of Matlab; these will not be described here.

1. Getting started with Matlab

   Login to one of the machines in Ayres 15 using your UTK username and password. This should be the same login information you use to access your university email account. Next, go to the start menu and select 'Matlab 7.0' under 'Programs/Math and Statistics Software'

2. Learning the commands

   Follow through the instructions on pages 19-20 of the course supplement. This will introduce you to all the commands needed to complete the project with examples of exactly what you should type. If you forget what a command does or which commands to use after completing this step, try using help and lookfor in Matlab. For example,

   • lookfor standard looks for all commands with the word 'standard' in the help text (such as standard deviation).
   • help median gives help on the 'median' command

3. Practicing the commands

   Complete a practice version of the matlab component of project 2 using the following data set. I have provided my Matlab output together with the parameters I used in the commands. To ensure that you are using Matlab correctly, you should check that your output matches mine. Note that your Matlab output from project 2 will differ substantially according to the data you gather.

   I have generated some ficticious data representing number of handwashings per day versus number of sick days per year for randomly selected UT students. Each column of the table below represents a single individual.

   
   

   Handwashings per day	3	3	3	5	5	6	7	7	8	9	12	13	13	15	16	16	18	19	20	20
   Sick days per year	45	40	37	35	33	37	31	35	30	35	26	29	21	24	26	19	22	13	11	13

   
   
   Statistics for handwashings:
   • Mean: 10.9000
   • Standard deviation: 5.9991
   • Variance: 35.9895
   • Histogram with 7 classes:
     
     (Note that the histogram doesn't label tick marks for the class limits by default. This is fine.)
   Statistics for sick days:
   • Mean: 28.1000
   • Standard deviation: 9.4863
   • Variance: 89.9895
   • Histogram with 7 classes:
     
     
   Bivariate statisitics (x=hand washings, y=sick days):
   • Correlation coefficient: -0.9394
   • Regression equation: y=-1.4855x+44.2922
   • Interpolated value: hand washings=11.500, sick days=27.2087
   • Extrapolated value: hand washings=24, sick days=8.6397
   • Scatter plot/regression graph with a domain of [2,21]:
     
     
   Bivariate statisitics (x=sick days, y=hand washings):
   • Correlation coefficient: -0.9394
   • Regression equation: y=-0.5941x+27.5943
   • Interpolated value: sick days=28, hand washings=10.9594
   • Extrapolated value: sick days=54, hand washings=-4.4873
   • Scatter plot/regression graph: