This preview shows pages 1–2. Sign up to view the full content.
1
Statistics is the science of using data to answer questions. We begin the process by first defining
a problem and stating the corresponding research question. Then, we plan how to collect relevant
data and obtain that data by implementing the plan. Next we analyze the data with numerical
summaries and graphs. Finally, we draw conclusions from our data to answer the research
question.
Statistics is the science of learning from data.
Data are numbers with a context.
The individual is the basic unit in the population.
The variable is the characteristic recorded on EACH individual by the researcher.
Categorical variable:
not numbers with value, asking respondents to select a category (no matter
a number or not)
Quantitative variable: a number having value
Bar graphs are the recommended plot for categorical data. Pie charts are not recommended by
statisticians.
Since the bars tail off on the right, we say the distribution is rightskewed. (zuo gao you di)
The key concept in statistics: variation
2
ORGANIZING A STATISTICAL PROBLEM: A FOURSTEP PROCESS
STATE: What is the practical question, in the context of the realworld setting?
PLAN: What specific statistical operations does this problem call for?
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview. Sign up
to
access the rest of the document.
 Winter '11
 PattiColling
 Statistics

Click to edit the document details