Analysis of the Human Face(continued)

9/15/06

IMPORTANT!

• Any new students should identify themselves to Dr. Pergolizzi NOW, to obtain a book, and a course outline.– These students will be instructed on how to take the

“face measurements”– Data they generate will be added to the database

we will build today

• ALL students should take a copy of the handout and the new, improved course outline!

What did we measure?

• Length of Ear

• Interpupillary Distance

• Length of face

• Width of face– 2 measurements (ear to nose, both sides)

• Length of nose

How will we analyze the data?

• Measurements for each subject will be entered into an Excel spreadsheet and used to calculate:– Mean, deviation, variance and standard deviation

• Data will be combined to analyze– Group 1 vs. group 2– Male vs female– Other groupings?

• Differences between groups will be analyzed for significance using the student’s t test

Students will:• Enter the measurements they obtained into a

database– See “face datafile”

• Upon completion of the database each student will take a copy. – Can use disk, flashdrive, or e-mail to yourself

• For each set of measurements (e.g., subject X, interpupillary distance) calculate mean, variance and standard deviation (SD)– Insert columns as required

• For the entire group of measurements (e.g., group A interpupillary distance) calculate overall mean, variance and SD– Insert columns as required

Extra Credit

• Any student who did the extra credit exercise…– Obtain data from the internet or other source on

facial data from another population• E.g., distance between eyes as a function of gender, age,

etc.

…is encouraged to share their findings with the group

What does the analysis mean?

• Have we introduced any biases into our measurement?

• Is what we have done an “experiment”?

• What conclusions can be drawn from our measurements? Can we extrapolate to the general population?

• What would you do to improve the quality and/or significance of the data?

For Next Time:• Analyze the data for “Group A vs Group B” for

significance as determined by the student’s t test with p<0.05

• Please read Chapters 11 and 12 (page 167) in “The Art of Science”.

• Now is the time to begin to think about your research projects!– Please come to chat with Dr. Pergolizzi and/or Ms. Leonardi

to begin the process of identifying and refining an interesting research project that could be accomplished in the limited time available