Unit 1 Tutorials: Key Principles of
Statistical Methods
INSIDE UNIT 1
Statistics Fundamentals
Statistics Overview
Data
Qualitative and Quantitative Data
Discrete vs. Continuous Data
Sampling
Sampling
Random & Probability Sampling
Simple Random and Systematic Random Sampling
Stratified Random and Cluster Sampling
Multi-Stage Sampling
Experiments
Observational Studies and Experiments
Prospective and Retrospective Studies
Experimental Design
Randomized Block Design
Completely Randomized Design
Matched-Pair Design
Surveys
Blinding
Placebo
Data
Variables
Question Types
Page 1
, Accuracy and Precision in Measurements
Absolute Change and Relative Change
Using Percentages in Statistics
Index Number and Reference Value
Studies
Bias
Nonresponse and Response Bias
Selection and Deliberate Bias
Convenience & Self-Selected Samples
Random and Systematic Errors
Margin of Error
Statistics Overview
by Sophia
WHAT'S COVERED
Statistics
Types of Statistics
1. Statistics
You might be wondering, what is statistics? Is it some complicated formula? Is it some goofy graph that you
really don't know that much about?
When people refer to statistics, they're usually referring to information called data that's been collected and
synthesized within a statistical study and sometimes presented in a graphical form, like this:
Page 2
,While the image may be small and difficult to read, you get the idea that a LOT of information can be presented
in the form of a graph.
It can also be presented numerically, such as “The median household income in the United States is $46,326.”
WATCH
STEP BY STEP
The practice of statistics deals with four main steps:
. Collect. Collect the information from a variety of sources.
. Analyze. Analyze the information that you've collected.
. Interpret. Interpret what that analysis means.
Page 3
, . Present. Present it in a way that anyone can understand.
Statistics is a neat way to describe a messy world. It's not pretty all the time. But statistics allows us a way to
simplify things down.
TERMS TO KNOW
Statistics
The study of collecting, analyzing, interpreting, and presenting information.
Statistical Study
A way to collect information from individuals.
2. Types of Statistics
When you use descriptive statistics, you are going to analyze what's going on at a particular point and use
statistics to describe the information that you've obtained.
On the other hand, when you use inferential statistics, you are going to use statistics that you've obtained and
make a generalization about the population at large.
IN CONTEXT
Let's say that you read the newspaper this morning and discovered that the average household
This information didn't come from sampling every household in the United States. It wouldn't be
Well, a sample was taken, and a generalization was made about the entire United States based on
that sample.
This is inferential statistics.
TERMS TO KNOW
Descriptive Statistics
Using only the information at hand to describe the selected group of individuals.
Inferential Statistics
Using the information at hand to make a larger, more general statement about the entire population of
individuals.
Page 4
Statistical Methods
INSIDE UNIT 1
Statistics Fundamentals
Statistics Overview
Data
Qualitative and Quantitative Data
Discrete vs. Continuous Data
Sampling
Sampling
Random & Probability Sampling
Simple Random and Systematic Random Sampling
Stratified Random and Cluster Sampling
Multi-Stage Sampling
Experiments
Observational Studies and Experiments
Prospective and Retrospective Studies
Experimental Design
Randomized Block Design
Completely Randomized Design
Matched-Pair Design
Surveys
Blinding
Placebo
Data
Variables
Question Types
Page 1
, Accuracy and Precision in Measurements
Absolute Change and Relative Change
Using Percentages in Statistics
Index Number and Reference Value
Studies
Bias
Nonresponse and Response Bias
Selection and Deliberate Bias
Convenience & Self-Selected Samples
Random and Systematic Errors
Margin of Error
Statistics Overview
by Sophia
WHAT'S COVERED
Statistics
Types of Statistics
1. Statistics
You might be wondering, what is statistics? Is it some complicated formula? Is it some goofy graph that you
really don't know that much about?
When people refer to statistics, they're usually referring to information called data that's been collected and
synthesized within a statistical study and sometimes presented in a graphical form, like this:
Page 2
,While the image may be small and difficult to read, you get the idea that a LOT of information can be presented
in the form of a graph.
It can also be presented numerically, such as “The median household income in the United States is $46,326.”
WATCH
STEP BY STEP
The practice of statistics deals with four main steps:
. Collect. Collect the information from a variety of sources.
. Analyze. Analyze the information that you've collected.
. Interpret. Interpret what that analysis means.
Page 3
, . Present. Present it in a way that anyone can understand.
Statistics is a neat way to describe a messy world. It's not pretty all the time. But statistics allows us a way to
simplify things down.
TERMS TO KNOW
Statistics
The study of collecting, analyzing, interpreting, and presenting information.
Statistical Study
A way to collect information from individuals.
2. Types of Statistics
When you use descriptive statistics, you are going to analyze what's going on at a particular point and use
statistics to describe the information that you've obtained.
On the other hand, when you use inferential statistics, you are going to use statistics that you've obtained and
make a generalization about the population at large.
IN CONTEXT
Let's say that you read the newspaper this morning and discovered that the average household
This information didn't come from sampling every household in the United States. It wouldn't be
Well, a sample was taken, and a generalization was made about the entire United States based on
that sample.
This is inferential statistics.
TERMS TO KNOW
Descriptive Statistics
Using only the information at hand to describe the selected group of individuals.
Inferential Statistics
Using the information at hand to make a larger, more general statement about the entire population of
individuals.
Page 4
