1. Statistics and the Scientific Method
Chapter 1
Statistics and the Scientific Method

2. Introduction Applied Statistics generalizes into 4-step process:
Problem Definition/Description
Data Collection
Data Description/Summarization
Data Analysis/Interpretation/Communication
Many methods exist to complete this process for many types of data and experimental settings

3. Examples of Practical Problems
New Drug Testing: Does a new drug improve patient condition more so than an existing drug or placebo?
Quality Control: Does a manufacturing facility continue to have an acceptable rate of defectives?
Political Polling: What proportion of adults favor a particular political stance or candidate?
Measuring Animal Poulations: How many fish of a particular species live in a lake?
Agricultural Production: Which of 4 varieties of fertilizer give best results in grain production?
Marketing: What levels of pricing and advertising produce the highest profits for a new product?

4. Populations and Samples
Population: All measurements of interest to researcher
Sample: Subset of population that is obtained and to be analyzed
Population
Sample

5. Statistical Inference
Goal: Make statements regarding a population (or true state of nature) based on observations from a sample.
What can be said of the average measurement in a population, when we obtain the average of a sample from the population?
Can we conclude success rates differ for two treatments in nature (across a conceptual population of units), based on a certain difference in success rates in two samples of units that were assigned the treatments