Descriptive Statistics, Graphical Displays, and Regression Basics

Apuntes

Unit 1 MGSC 291 Exam 1 List of Topics Statistics - Basics and Definitions ❖ Descriptive Statistics ➢ Collecting, Organizing, Summarizing, and Presenting the data ❖ Inferential Statistics ➢ Drawing conclusions about a population based on data observed on a sample from that population ❖ Population ➢ Parameter ■ Number used to describe/summarize the population ➢ Sample ■ Statistic ● Number calculated from a sample ● Used to estimate the parameter ■ Observational unit ● The unit upon which an observation is made ❖ Variables ➢ Columns of the dataset ❖ Observation Units ➢ Rows of the dataset ❖ Quantitative ➢ Discrete ■ Counted ■ Ex. Number of hummingbirds ➢ Continuous ■ Measured ■ Ex. Distance of hummingbirds from my patio ❖ Qualitative (Categorical) ➢ Non-numerical values ➢ Numbers that dont have magnitudinal meaning ■ Zip Code, area code ➢ Identifier Variables ■ SSNs and other ID numbers ➢ Nominal Values ■ Values that cannot be ordered ■ Ex. A UofSC undergraduate student’s major ➢ Ordinal Values ■ When data can be ordered ■ Ex. A UofSC undergraduate student’s class year Graphical Displays ❖ Qualities of a good graphical display ➢ Things to avoid ■ 3-D graphs ■ Violations of the “area p...