Chapter 7.1 statistics The degrees of freedom for this t statistic come from the sample standard deviation s in the denominator of t The density curves of the t(k) distributions are smaller in shape to the standard normal curve. That is, they
Chapter 3 I. Our goal in choosing a sample is a picture of the population, disturbed as little as possible by the act of gathering information II. Sample surveys are one kind of observational study III. In doing an experiment, we dont just observe in
Chapter 2 I. A response variable measures an outcome of a study II. An explanatory variable explains or influences changes in a response variable III. Scatter plots A. The most common way to display relation between two quantitative variables is a sc
Statistics 309- chapter 1 I. Mean and Median A. The mean uses the actual value of each observation and so will chase a single small observation downward. B. The mean and median of symmetric distribution are close together C. If the mean and median ar
Variables: the characteristics of the individuals. Individuals may be people or objects. A variable can take different values for different individuals.
Categorical variables: record which category a person or thing falls into. lists the categories a