Four Basic Designs

Prof Randi Garcia
January 5, 2021

Reading contemplation question

  1. Was this design principal of crossing present in Kelly's hamster experiment?

Announcements

  • Slack issues?
  • Registration
  • Zoom login tomorrow for breakout rooms
    • Complete the course survey (Moodle)
  • Lord of the rings!

Our First Experiment

Get in breakout groups of ~8 we will discuss.

As you participate in the experiment at the link below, remember:

  • what you saw
  • what you did
  • the order in which it happened.

To participate, find the experiment link in the course schedule!! http://bit.ly/sds290interterm21

Kelly's Hamster Study

Blocking + Random Assignment + Crossing

Design 4: Split Plot/Repeated Measures Design

  • SP/RM[1,1]

The Meats

Randomized Basic Factorial Design BF[1]

The shelf life of meats is the time a prepackaged cut remains salable, safe, and nutritious. Recent studies suggested controlled gas atmospheres as possible alternatives to existing packaging. To test this, beef steaks (75g) were randomly assigned to packaging with either 1) ambient air in a commercial plastic wrap, 2) vacuum packed, 3) 100% carbon dioxide (CO2), or 4) a mixture of 1% carbon monoxide (CO), 40% oxygen (O2), and 59% nitrogen (N). The number of psychrotrophic bacteria on the meat was measured after nine days of storage at 4 degrees C.