Hey everyone! I just wanted to give you the heads up on a book project that I’ve been working on (which should be available by Spring 2016). It’s all about using the R programming language to do simulation — which I think is one of the most powerful (and overlooked) tools in data science. Please feel free to email or write comments below if you have any suggestions for material you’d like to have included in it!
Originally, this project was supposed to be a secret… I’ve been working on it for about two years now, along with two other writing projects, and was approached in June by a traditional publishing company (who I won’t mention by name) who wanted to brainstorm with me about possibly publishing and distributing my next book. After we discussed the intersection of their wants and my needs, I prepared a full outline for them, and they came up with a work schedule and sent me a contract. While I was reading the contract, I got cold feet. It was the part about giving up “all moral rights” to my work, which sounds really frightening (and is not something I have to do under creative commons licensing, which I prefer). I shared the contract with a few colleagues and a lawyer, hoping that they’d say don’t worry… it sounds a lot worse than it really is. But the response I got was it sounds pretty much like it is.
While deliberating the past two weeks, I’ve been moving around a lot and haven’t been in touch with the publisher. I got an email this morning asking for my immediate decision on the matter (paraphrased, because there’s a legal disclaimer at the bottom of their emails that says “this information may be privileged” and I don’t want to violate any laws):
If we don’t hear from you, unfortunately we’ll be moving forward with this project. Do you still want to be on board?
The answer is YEAH – of COURSE I’m “on board” with my own project. But this really made me question the value of a traditional publisher over an indie publisher, or even self-publishing. And if they’re moving forward anyway, does that mean they take my outline (and supporting information about what I’m planning for each chapter) and just have someone else write to it? That doesn’t sound very nice. Since all the content on my blog is copyrighted by ME, I’m sharing the entire contents of what I sent to them on July 6th to establish the copyright on my outline in a public forum.
So if you see this chapter structure in someone ELSE’S book… you know what happened. The publisher came up with the idea for the main title (“Simulation for Data Science With R”) so I might publish under a different title that still has the words Simulation and R in them.
I may still publish with them, but I’ll make that decision after I have the full manuscript in place in a couple months. And after I have the chance to reflect more on what’s best for everyone. What do you think is the best route forward?
Simulation for Data Science With R
Effective Data-Driven Decision Making for Business Analysis by Nicole M. Radziwill
Audience
Simulation is an essential (yet often overlooked) tool in data science – an interdisciplinary approach to problem-solving that leverages computer science, statistics, and domain expertise. This easy-to-understand introductory text for new and intermediate-level programmers, data scientists, and business analysts surveys five different simulation techniques (Monte Carlo, Discrete Event Simulation, System Dynamics, Agent-Based Modeling, and Resampling). The book focuses on practical and illustrative examples using the R Statistical Software, presented within the context of structured methodologies for problem solving (such as DMAIC and DMADV) that will enable you to more easily use simulation to make effective data-driven decisions. Readers should have exposure to basic concepts in programming but can be new to the R Statistical Software.
Mission
This book helps its readers 1) formulate research questions that simulation can help solve, 2) choose an appropriate problem-solving methodology, 3) choose one or more simulation techniques to help solve that problem, 4) perform basic simulations using the R Statistical Software, and 5) present results and conclusions clearly and effectively.
Objectives and achievements
The reader will:
- Learn about essential and foundational concepts in modeling and simulation
- Determine whether a simulation project is also a data science project
- Choose an appropriate problem-solving methodology for effective data-driven decision making
- Select suitable simulation techniques to provide insights about a given problem
- Build and interpret the results from basic simulations using the R Statistical Software
SECTION I: BASIC CONCEPTS
- Introduction to Simulation for Data Science
- Foundations for Decision-Making
- SECRET NEW CHAPTER THAT YOU WILL BE REALLY EXCITED ABOUT
SECTION II: STOCHASTIC PROCESSES
- Variation and Random Variable Generation
- Distribution Fitting
- Data Generating Processes
SECTION III: SIMULATION TECHNIQUES
- Monte Carlo Simulation
- Discrete Event Simulation
- System Dynamics
- Agent-Based Modeling
- Resampling Methods
- SECRET NEW CHAPTER THAT YOU WILL BE REALLY EXCITED ABOUT
SECTION IV: CASE STUDIES
- Case Study 1: Possibly modeling opinion dynamics… specific example still TBD
- Case Study 2: A Really Practical Application of Simulation (especially for women)
Chapter 1: Introduction to Simulation for Data Science – 35 pages
Description
This chapter explains the role of simulation in data science, and provides the context for understanding the differences between simulation techniques and their philosophical underpinnings.
Level
BASIC
Topics covered
Variation and Data-Driven Decision Making
What are Complex Systems?
What are Complex Dynamical Systems? What is systems thinking? Why is a systems perspective critical for data-driven decision making? Where do we encounter complex systems in business or day-to-day life?
What is Data Science?
A Taxonomy of Data Science. The Data Science Venn Diagram. What are the roles of modeling and simulation in data science projects? “Is it a Data Science Project?” — a Litmus Test. How modeling and simulation align with data science.
What is a Model?
Conceptual Models. Equations. Deterministic Models, Stochastic Models. Endogeneous and Exogenous Variables.
What is Simulation?
Types of Simulation: Static vs. Dynamic, Stochastic vs. Deterministic, Discrete vs. Continuous, Terminating and Non-Terminating (Steady State). Philosophical Principles: Holistic vs. Reductionist, Kadanoff’s Universality, Parsimony, Sensitivity to Initial Conditions
Why Use Simulation?
Simulation and Big Data
Choosing the Right Simulation Technique
Skills learned
The reader will be able to:
- Distinguish a model from a simulation
- Explain how simulation can provide a valuable perspective in data-driven decision making
- Understand how simulation fits into the taxonomy of data science
- Determine whether a simulation project is also a data science project
- Determine which simulation technique to apply to various kinds of real-world problems
Chapter 2: Foundations for Decision Making – 25 pages
Description
In this chapter, the reader will learn how to plan and structure a simulation project to aid in the decision-making process as well as the presentation of results. The social context of data science will be explained, emphasizing the growing importance of collaborative data and information sharing.
Level
BASIC
Topics covered
The Social Context of Data Science
Ethics and Provenance. Data Curation. Replicability, Reproducibility, and Open Science. Open, interoperable frameworks for collaborative data and information sharing. Problem-Centric Habits of Mind.
Selecting Key Performance Indicators (KPIs)
Determining the Number of Replications
Methodologies for Simulation Projects
A General Problem-Solving Approach
DMAIC
DMADV
Root Cause Analysis (RCA)
PDSA
Verification and Validation Techniques
Output Analysis
Skills learned
The reader will be able to:
- Plan a simulation study that is supported by effective and meaningful metadata
- Select an appropriate methodology to guide the simulation project
- Choose activities to ensure that verification and validation requirements are met
- Construct confidence intervals for reporting simulation output
Chapter 3: Variability and Random Variate Generation – 25 pages
Description
Simulation is powerful because it provides a way to closely examine the random behavior in systems that arises due to interdependencies and variability. This requires being able to generate random numbers and random variates that come from populations with known statistical characteristics. This chapter describes how random numbers and random variates are generated, and shows how they are applied to perform simple simulations.
Level
MEDIUM
Topics covered
Variability in Stochastic Processes
Why Generate Random Variables?
Pseudorandom Number Generation
Linear Congruential Generators
Inverse Transformation Method
Using sample for Discrete Distributions
Is this Sequence Random? Tests for Randomness
Autocorrelation, Frequency, Runs Tests. Using the randtests package
Tests for homogeneity
Simple Simulations with Random Numbers
Skills learned
The reader will be able to:
- Generate pseudorandom numbers that are uniformly distributed
- Use random numbers to generate random variates from a target distribution
- Perform simple simulations using streams of random numbers
Chapter 4: Data Generating Processes – 30 pages
Description
To execute a simulation, you must be able to generate random variates that represent the physical process you are trying to emulate. In this chapter, we cover several common statistical distributions that can be used to represent real physical processes, and explain which physical processes are often modeled using those distributions.
Level
MEDIUM
Topics covered
What is a Data Generating Process?
Continuous, Discrete, and Multivariate Distributions
Discrete Distributions
Binomial Distribution
Geometric Distribution
Hypergeometric Distribution
Poisson Distribution
Continuous Distributions
Exponential Distribution
F Distribution
Lognormal Distribution
Normal Distribution
Student’s t Distribution
Uniform Distribution
Weibull Distribution
Chi2 Distribution
Stochastic Processes
Markov. Poisson. Gaussian, Bernoulli. Brownian Motion. Random Walk.
Stationary and Autoregressive Processes.
Skills learned
The reader will be able to:
- Understand the characteristics of several common discrete and continuous data generating processes
- Use those distributions to generate streams of random variates
- Describe several common types of stochastic processes
Chapter 5: Distribution Fitting – 30 pages
Description
An effective simulation is driven by data generating processes that accurately reflect real physical populations. This chapter shows how to use a sample of data to determine which statistical distribution best represents the real population. The resulting distribution is used to generate random variates for the simulation.
Level
MEDIUM
Topics covered
Why is Distribution Fitting Essential?
Techniques for Distribution Fitting
Shapiro-Wilk Test for Normality
Anderson-Darling Test
Lillefors Test
Kolmogorov-Smirnov Test
Chi2 Goodness of Fit Test
Other Goodness Of Fit Tests
Transforming Your Data
When There’s No Data, Use Interviews
Skills learned
The reader will be able to:
- Use a sample of real data to determine which data generating process is required in a simulation
- Transform data to find a more effective data generating process
- Estimate appropriate distributions when samples of real data are not available
Chapter 6: Monte Carlo Simulation – 30 pages
Description
This chapter explains how to set up and execute simple Monte Carlo simulations, using data generating processes to represent random inputs.
Level
ADVANCED
Topics covered
Anatomy of a Monte Carlo Project
The Many Flavors of Monte Carlo
The Hit-or-Miss Method
Example: Estimating Pi
Monte Carlo Integration
Example: Numerical Integration of y = x2
Estimating Variables
Monte Carlo Confidence Intervals
Example: Projecting Profits
Sensitivity Analysis
Example: Projecting Variability of Profits
Example: Projecting Yield of a Process
Markov Chain Monte Carlo
Skills learned
The reader will be able to:
- Plan and execute a Monte Carlo simulation in R
- Construct confidence intervals using the Monte Carlo method
- Determine the sensitivity of process outputs and interpret the results
Chapter 7: Discrete Event Simulation – 30 pages
Description
What is this chapter about?
Level
ADVANCED
Topics covered
Anatomy of a DES Project
Entities, Locations, Resources and Events
System Performance Metrics
Queuing Models and Kendall’s Notation
The Event Calendar
Manual Event Calendar Generation
Example: An M/M/1 system in R
Using the queueing package
Using the simmer package
Arrival-Counting Processes with the NHPoisson Package
Survival Analysis with the survival Package
Example: When Will the Bagels Run Out?
Skills learned
The reader will be able to:
- Plan and execute discrete event simulation in R
- Choose an appropriate model for a queueing problem
- Manually generate an event calendar to verify simulation results
- Use arrival counting processes for practical problem-solving
- Execute a survival analysis in R and interpret the results
Chapter 8: System Dynamics – 30 pages
Description
This chapter presents system dynamics, a powerful technique for characterizing the effects of multiple nested feedback loops in a dynamical system. This technique helps uncover the large-scale patterns in a complex system where interdependencies and variation are critical.
Level
ADVANCED
Topics covered
Anatomy of a SD Project
The Law of Unintended Consequences and Policy Resistance
Introduction to Differential Equations
Causal Loop Diagrams (CLDs)
Stock and Flow Diagrams (SFDs)
Using the deSolve Package
Example: Lotka-Volterra Equations
Dynamic Archetypes
Linear Growth
Exponential Growth and Collapse
S-Shaped Growth
S-Shaped Growth with Overshoot
Overshoot and Collapse
Delays and Oscillations
Using the stellaR and simecol Packages
Skills learned
The reader will be able to:
- Plan and execute a system dynamics project
- Create causal loop diagrams and stock-and-flow diagrams
- Set up simple systems of differential equations and solve them with deSolve in R
- Predict the evolution of stocks using dynamic archetypes in CLDs
- Convert STELLA models to R
Chapter 9: Agent-Based Modeling – 25 pages
Description
Agent-Based Modeling (ABM) provides a unique perspective on simulation, illuminating the emergent behavior of the whole system by simply characterizing the rules by which each participant in the system operates. This chapter provides an overview of ABM, compares and contrasts it with the other simulation techniques, and demonstrates how to set up a simulation using an ABM in R.
Level
ADVANCED
Topics covered
Anatomy of an ABM Project
Emergent Behavior
PAGE (Percepts, Actions, Goals, and Environment)
Turtles and Patches
Using the RNetLogo package
Skills learned
The reader will be able to:
- Plan and execute an ABM project in R
- Create specifications for the ABM using PAGE
Chapter 10: Resampling – 25 pages
Description
Resampling methods are related to Monte Carlo simulation, but serve a different purpose: to help us characterize a data generating process or make inferences about the population our data came from when all we have is a small sample. In this chapter, resampling methods (and some practical problems that use them) are explained.
Level
MEDIUM
Topics covered
Anatomy of an Resampling Project
Bootstrapping
Jackknifing
Permutation Tests
Skills learned
The reader will be able to:
- Plan and execute a resampling project in R
- Understand how to select and use a resampling technique for real data
Chapter 11: Comparing the Simulation Techniques – 15 pages
Description
In this chapter, the simulation techniques will be compared and contrasted in terms of their strengths, weaknesses, biases, and computational complexity.
Level
ADVANCED
Topics covered
TBD – at least two simulation approaches will be applied
Skills learned
The reader will learn how to:
- Think about a simulation study holistically
- Select an appropriate combination of techniques for a real simulation study