University:
Missouri State University
Course:
MTH 343 | Foundations of Probability and Statistics for Teachers
Academic year:

2021
Views:

62

Pages:

8
Author:

Alecai8y

Randomized Comparative Experiments ` Subjects are randomly assigned to one of at least two treatment groups. ` The same response variable is measured for all the treatment groups and then compared together. x x Randomized Comparative Experiments ` Randomization is important so that bias is not added into the selection of treatment groups. Ex. In a clinical trial a researcher may unconsciously place healthier looking patients into the group getting the new drug on interest. Control Group – treatment group that will get a placebo, current treatment, or no treatment but not the new treatment. ` Helps in the comparison of the effectiveness of the new treatment. ` Diagram of Example 1 New Soil(10) Randomization 20 Rose Bushes Compare : • Size • Color • Health Between 2 groups Current Soil(10) Diagram of Example 3 80 Overweight Adult Males Randomization Low Carb/Aerobic(20) Low Carb/Pilates(20) Low Fat/Aerobic(20) Low Fat/Pilates(20) Compare Weight Loss of men between 4 Groups Example 4 ` ` ` ` Explanatory – Drug Used Treatments – New Drug and Old Drug Subjects – 100 volunteers with high cholesterol and not on medication Response – changes in cholesterol level Placebo? – should not be used since high cholesterol is life-threatening 100 Volunteers w/ High Cholesterol and not on Medication Randomization ` New Drug(50) Compare Changes in Cholesterol Level between the 2 Groups Current Drug(50) Example 5 ` ` ` Explanatory Variables – Salinity and Nutrients Treatments – 6; A-High, A-Low, B-High, B-Low, C-High, C-Low Subjects – The shrimp in the 12 tanks Response – Growth of the shrimp A – High(2) 12 Tanks of Shrimp Randomization ` A – Low(2) B – High(2) B – Low(2) C – High(2) C – Low(2) Compare growth of the shrimp between the 6 groups Example 6 ` ` ` ` Explanatory – Dietary Suppliment Treatments – Glucosamine and Chondroitin Subjects – 300 Dogs Response – Changes in joint and hip health Control Group? A control group would give a good comparison of joint and hip health in health dogs compared to dogs on the two drugs. 300 Dogs Randomization ` Glucosamine(100) Chondrotin(100) Nothing(100) Compare Hip and Joint Health Between the 3 Groups