Chapter 1 What is your goal?

1.1 Exploratory or hypothesis generation

1.2 Inferential or hypothesis testing “Are things different”

This is a hypothesis, not a description. Description can highlight, but doesn’t test what’s different. Descriptions can still have a bias (mean vs median vs range all show different things descriptively, PCA problems). Doesn’t mean it’s an experiment.

summary(cars)

##      speed           dist       
##  Min.   : 4.0   Min.   :  2.00  
##  1st Qu.:12.0   1st Qu.: 26.00  
##  Median :15.0   Median : 36.00  
##  Mean   :15.4   Mean   : 42.98  
##  3rd Qu.:19.0   3rd Qu.: 56.00  
##  Max.   :25.0   Max.   :120.00

1.3 Physical or mechanistic predictions - you can only statistics them away sometimes

You can also embed plots, for example:

Note that the echo = FALSE parameter was added to the code chunk to prevent printing of the R code that generated the plot.