Statistics Experimental Design

• Treatment (+) row = 50

  Treatment (-) row = 50

• Treatment (+) row = 25

  Treatment (-) row = 75

• Treatment (+) row = 75

  Treatment (-) row = 25

• Treatment (+) row = 100

  Treatment (-) row = 0

• Treatment (+) row = 0

  Treatment (-) row = 200

• 1.33

• 2.67

• 4.00

• 5.33

What is the odds ratio (OR) for the data in the contingency table shown?

• 1.71

• 0.58

• 1.28

• 0.78

What is the relative risk (RR) for the data in the contingency table shown?

• 1.71

• 0.58

• 1.28

• 0.78

A ​ (a)   should include

the following:

a. ​ (b)   of at least two treatment

groups, one of which could be a

control group.

b. ​ (c)   assignment/allocation of

treatments to experimental units.

c. ​ (d)   (more than one experimental

unit in each treatment group).

d. ​ (e)   of potential confounding variables

where appropriate

• well-designed experiment

• Comparisons

• Random

• Replication

• Control

Which of the following table designs would have 6 df in a \chi^2 test?

• 3 columns, 3 rows

• 4 columns, 4 rows

• 3 columns, 4 rows

• 4 columns, 5 rows

A market research company wishes to find out whether the population of students at a university prefers Starbucks or Dunkin Donuts. A random sample of students is selected, and each student is asked first to try both but the order they try them is randomly decided with a coin toss (heads: Starbucks, then Dunkin. tails: vice versa). They then indicate which brand they prefer. This is an example of

• completely randomized experiment

• an observational study

• blocked experiment

• matched pairs experiment

In order to perform an experiment using 60 members of a gym, I first divide the list of members into men and women because I feel that the results will be different based on gender. I then randomly choose 30 men and 30 women. I assign half of the men to the treatment group and half to the control group. I repeat this procedure with the women. This is an example of a:

• completely randomized experiment

• blocked experiment

• matched pairs experiment

• observational study

Researchers want to know how diet influences a child's brain development. In a sample of 100 5 year old children, 20 of the children are given a vegan diet, 20 are given a pescatarian diet, 20 are given a standard American diet, and 20 are given a paleo diet. This is an example of...

• a matched pair, with pairs determined by diet type

• a block design, with blocks determined by age.

• a block design, with blocks determined by diet type.

• a completely randomized experiment

Dentists want to know if a fluoride mouth wash will help prevent cavities. After 6 months, they will compare the number of cavities in those who used the mouth wash versus those who did not. Which is an example of a matched pairs design for this experiment?

• Dentists sort 40 patients into groups based on age, such as 10-14, 15-20, 21-26, and 26-30. Half of the patients in each group are given the mouth wash, half are not.

• Dentists sort 50 patients into pairs that are the same age. 1 person is given the mouth wash and 1 is not.