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Tag Archives: Confounding
Learning from bad experiments
Thinking about bad experiments is a good device helping reinforce the concepts of experimental design. No one should deliberately perform an experiment with a defective design. However, thinking about such designs is a great learning device. For example, why does … Continue reading
Posted in Observational Studies, Randomized Experiments, Statistical studies, Statistics
Tagged Completely Randomized Experimental Design, Confounding, Double blind, Experiments, Introduction to statistics, Introductory statistics, Lurking variables, Observational studies, Placebo, Randomized Experiments
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Thinking about study designs
When learning the designs of research studies, an effective exercise is to look at examples drawn from actual research studies. In this post, we present a series of eight research studies. For each study, the exercise is to classify each … Continue reading
Design of Observational Studies
There are numerous ways to collect data when conducting research. The study design depends greatly on the nature of the research question. There are two key areas of statistics that provide ways of collecting data, namely the idea of sampling … Continue reading
Design of experiments
When the goal in a statistical study is to understand cause and effect, experiments are the only way to obtain convincing evidence for causation. This is an introductory discussion on experimental design, introducing its vocabulary, its characteristics and its principles. … Continue reading
Posted in Randomized Experiments, Statistical studies, Statistics
Tagged Completely Randomized Experimental Design, Confounding, Correlation, Double blind, Experiments, Introduction to statistics, Introductory statistics, Lurking variables, Observational studies, Placebo, Randomized Experiments
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What science learned from a group of elderly nuns
The Nun Study is a longitudinal study of aging and Alzheimer’s disease. It followed 678 sisters of the School Sisters of Notre Dame living in Mankato, Minnesota. The goal of the study is to identify the risk factors for Alzheimer’s … Continue reading