PS296 Chapter Notes - Chapter 1: Categorical Variable, Statistic
Three Decisions Fundamental to the Way We Look At Data and the Statistical Procedures
We Use to Help Us Interpret Those Data:
Types of Data (2 kinds):
Measurement/quantitative data:
-the result of any sort of measurement
-score on a meausre of stress
-some sort of instrument has been used to measure something
Categorical/frequency/count data:
-counting things and data consists of totals or frequencies for each category
-several hundred people may vote on something but results/data consist only of two numbers; the
number of votes for, and the number of votes against the proposal
-sometimes we can measure same gernal variable to produce either measurement or categorical
data
-latency score for each mouse = measurement data
-classifying mice as showing long, medium, or short latencies and then count the number in each
category = categorical data
Differences vs Relationships:
-different statistical techniques measuring differences vs relationships turn out to be basically the
Document Summary
Three decisions fundamental to the way we look at data and the statistical procedures. We use to help us interpret those data: Some sort of instrument has been used to measure something. Counting things and data consists of totals or frequencies for each category. Several hundred people may vote on something but results/data consist only of two numbers; the number of votes for, and the number of votes against the proposal. Sometimes we can measure same gernal variable to produce either measurement or categorical data. Latency score for each mouse = measurement data. Classifying mice as showing long, medium, or short latencies and then count the number in each category = categorical data. Different statistical techniques measuring differences vs relationships turn out to be basically the same fundamental procedure that ask somewhat different questions and phrase the answers in distinctly different ways. Independent t test: restricted to the case of data from at most 2 groups of subjects.
