“The 5 Second Rule”

Team 4

RESEARCH QUESTION:

Is the “5 Second Rule” true?

Subjects/Experimental Units: Food being dropped.

Explanatory Variables/Factors: How long the food is left on the ground. (Quantitative)

Response Variable: Number of germs on the food. (Quantitative)

TREATMENTS/FACTOR LEVELS

Treatments being used on the subjects in this experiment are

the lengths of time the food is on the ground to determine

whether or not the “5 Second Rule” is supported.

(3 seconds, 5 seconds, and Not Dropped.)

EXPERIMENTAL DESIGNThe first step in our experiment is to gather food to be dropped randomly by going to a variety of different kinds of stores and randomly assigning all the food a random, unique, number in each store. A number generator will generate 6000 unique random numbers and the corresponding food with those numbers will be selected. Then, the randomly selected food will be randomly blocked into 2 groups , hard flooring and carpet. (3000 in each group) From there, the groups will also be assigned randomly to the three different treatments, 3 secs, 5secs, and not being dropped. (1000 in each group) After all the germs are accounted for by an evaluator who doesn’t know how long the food has been on the ground, we will compare the food to look for a statistically significant result.

EXPERIMENTAL DESIGN

EXPERIMENTAL DESIGN PRINCIPLES

Control: The food not being dropped

Randomization: Randomly selecting and assigning food to groups to avoid bias.

Replication: We are using 6000 items of food to repeat the experiment. Specifically, we are using 1000 items of food for each group of flooring type and length of time.

BLOCKING

• In this experiment we did use blocking as we blocked the food into two groups of flooring type and then into three groups of different times.

BLINDING

• In this experiment we used blinding as the evaluator that looked at the food after the treatments were performed had no idea how long each item of food was on the ground in order to prevent bias.

CONCERNS AND ISSUES

• How accurate the evaluator is at determining the amount of germs on the food.

• How accurate each timing is for each item of food’s treatment.

• Whether or not different food acts differently.

CONCLUSIONSAfter collecting and reviewing all the data, and based off of previous experiments, we concluded that there’s no significant difference between food that has been on the floor for less or more than 5 seconds. So, the “5 Second Rule” is incorrect and just an urban myth. However, undropped food is obviously much more sanitary.