Database Reference
In-Depth Information
Interpreting Data
The final and perhaps most important step in the OSEMN model is interpreting data.
This step involves:
• Drawing conclusions from your data
• Evaluating what your results mean
• Communicating your result
To be honest, the computer is of little use here, and the command line does not really
come into play at this stage. Once you have reached this step, it is up to you. This is
the only step in the OSEMN model that does not have its own chapter. Instead, we
kindly refer you to
hinking with Data
by Max Shron (O'Reilly, 2014).
Intermezzo Chapters
In between the chapters that cover the OSEMN steps, there are three intermezzo
chapters. Each intermezzo chapter discusses a more general topic concerning data
science, and how the command line is employed for that. These topics are applicable
to any step in the data science process.
In
Chapter 4
, we discuss how to create reusable tools for the command line. These
personal tools can come from both long commands that you have typed on the com‐
mand line, or from existing code that you have written in, say, Python or R. Being
able to create your own tools allows you to become more efficient and productive.
Because the command line is an interactive environment for doing data science, it
can become challenging to keep track of your workflow. In
Chapter 6
, we demon‐
strate a command-line tool called Drake (Factual, 2014), which allows you to define
your data science workflow in terms of tasks and the dependencies between them.
This tool increases the reproducibility of your workflow, not only for you but also for
your colleagues and peers.
In
Chapter 8
, we explain how your commands and tools can be sped up by running
them in parallel. Using a command-line tool called GNU Parallel (Tange, 2014), we
can apply command-line tools to very large data sets and run them on multiple cores
and remote machines.
What Is the Command Line?
Before we discuss
why
you should use the command line for data science, let's take a
peek at
what
the command line actually looks like (it may already be familiar to you).
Figures
1-1
and
1-2
show a screenshot of the command line as it appears by default
