Exam 4: Estimation: How Large Is the Effect

Question

Researchers are interested in investigating the effect of a drug that is to be used in the treatment of patients who have glaucoma (an eye disorder associated with high eye pressure). In a volunteer sample of 35 patients with glaucoma in both eyes, one eye of each patient was randomly assigned to this drug, and the other eye was given a placebo. After one week, the eye pressure was measured on each eye. The difference in eye pressure between the two eyes (drug - placebo) was measured for each patient. The sample mean difference in eye pressure was -1.21 mmHg (millimeters of mercury), and the sample standard deviation of the differences was 4.67 mmHg. -A 98% theory-based confidence interval for the population mean difference in eye pressure is (-3.14, 0.72) mmHg.Does this interval give us evidence that the drug reduces eye pressure in glaucoma patients, on average?

Preliminaries: Introduction to Statistical Investigations

Significance: How Strong Is the Evidence

Generalization: How Broadly Do the Results Apply

Causation: Can We Say What Caused the Effect

Comparing Two Proportions

Comparing Two Means

Paired Data: One Quantitative Variable

Comparing More Than Two Proportions

Comparing More Than Two Means

Two Quantitative Variables

Modeling Randomness

Filters