Introduction

Data
Preprocess
Explore
Model
Communicate


Computing and Data Science

What is Data Science?

"In fact, some data scientists are — for all practical purposes — statisticians, while others are pretty much indistinguishable from software engineers. Some are machine-learning experts, while others couldn't machine-learn their way out of kindergarten...

In short, pretty much no matter how you define data science, you'll find practitioners for whom the definition is totally, absolutely wrong."
— Joel Grus, Data Science from Scratch, p. 20


Fayyad et al (1996). The KDD Process for Extracting Useful Knowledge from Volumes of Data
(Knowledge Discovery in Databases)

Chapman et al (1999), Wirth (2000). "Towards a standard process model for data mining".
1. Obtain: pointing and clicking does not scale
2. Scrub: the world is a messy place
3. Explore: You can see a lot by looking
4. Models: always bad, sometimes ugly
5. INterpret: "The purpose of computing is insight, not numbers."

Mason and Wiggins (2010). "A Taxonomy of Data Science".

Schutt and O'Neil (2014). "Doing Data Science: Straight talk from the frontline".

GAIMME Guidelines for assessment & instruction in mathematical modeling education (2016).

Guidelines for Assessment and Instruction in Statistics Education (GAISE) Reports
(2020, based on 2007).

Zico Kolter (2021). Practical Data Science, Intrdouction

Many frameworks. Much overlap.

Data
1. Get the data
Preprocess
2. Clean up the data
Explore
3. Explore the data
Model
4. Model it
Communicate
5. Share the results


Data Modeling Process


Data
Preprocess
Explore
Model
Communicate



Data Modeling Process

Data
Preprocess
Explore
Model
Communicate

Design
∘ Translate a problem into a data-problem.
∘ Survey or experimental design
∘ Database infrastructure
Acquire
∘ Survey or experiment
∘ Download the dataset! CSV, API, etc.
∘ Web scraping

Data Modeling Process

Data
Preprocess
Explore
Model
Communicate

Wrangle
∘ Format
∘ Clean and organize
∘ Check data integrity
Prepare
∘ Label
∘ Split into training and testing sets
∘ Normalize

Data Modeling Process

Data
Preprocess
Explore
Model
Communicate

Visualize
∘ Plot and familiarize with data
∘ Look for and compare features visually
∘ Consider appropriate models
Inspect
∘ Exploratory data analysis
∘ Descriptive statistics
∘ Identify features analytically

Data Modeling Process

Data
Preprocess
Explore
Model
Communicate

Model
∘ Try and compare multiple models
∘ Consider bias and variance
∘ Interpret model and performance
Validate
∘ Assess model performance on independent test data
∘ Error analysis and stress-test
∘ Consider consequences

Data Modeling Process

Data
Preprocess
Explore
Model
Communicate

Reflect
∘ Consider contexts, bias, and consequence
∘ Create audit plant
∘ Document - data and model
Share
∘ Report documentation
∘ Inform policy
∘ Deploy in product

Data Modeling Process


Data
Preprocess
Explore
Model
Communicate



Data Modeling Process


Environment

Data
Preprocess
Explore
Model
Communicate



A framework for critical analysis

Data
• Harmful data collection, lack of consent, insecure / lack of privacy, historical, representational, or measurement bias, ...

Preprocess
• Labor exploitation, labeling by non-experts, incorrect labeling, trauma experienced by labelers, ...

Explore
• Feature selection bias, bias in interpretation of data visualization, data manipulation, feature hacking, ...

Model
• Bias in model choice, model-amplified bias, environmental impact, learning bias, evaluation bias, peripheral modeling, ...

Communicate
• Biased model interpretation, ignoring variance, rejecting model, deploying harmful products, deployment bias, ...

Meta
• "Pernicious feedback loops", runaway homogeneity, susceptability to adversarial attack, lack of oversight or auditing, ...

Critical Questions:
  • What are the motivations for the project?
  • What is the intended use?
  • What is the unintended use or misuse?
  • Where does the data come from?
  • Who collects the data?
  • Who owns the data?
  • How is the data collected?
  • How is the data stored?
  • How old is the data?
  • When will the data expire?
  • How will the data be secured?
  • What happens with the data when the company is sold?
  • Who does the labeling?
  • What labels will they decide to use?
  • Are the labelers experts?
  • Are the labels accurate?
  • What biases are represented in the data?
  • How is data included or excluded?
  • How are outliers addressed?
  • What subpopulations are represented?
  • What subpopulations are over- or underrepresented?
  • What portions of the data are inspected?
  • What features are selected for modeling?
  • What model is chosen?
  • What features do we think are being modeled?
  • What latent features are actually being modeled?
  • What is the domain of the model?
  • What are the consequences of error?
  • What decisions will be made with the model?
  • What biases are perpetuated?
  • Where will the model be deployed?
  • What could go wrong?
  • Who is responsible when things go wrong?
  • How can issues be reported?
  • Will new data be fed back in to update the model?
https://medium.com/@blaisea/physiognomys-new-clothes-f2d4b59fdd6a
"Wu and Zhang’s sample ‘criminal’ images (top) and ‘non-criminal’ images (bottom)." 2016
"Simplistic stereotypes is really not a basis for developing AI, and if your AI is based on this then basically what you're doing is enshrining stereotypes in code." (11:42)
To what extent are we training
the next generation of pseudoscientists?

A common misconception is that

data + compute ⟶ solutions


If the problem isn't solved yet, it's just because you haven't added enough technology yet!

This is one facet of Technosolutionism



"Not only do many of the hiring tools not work, they are based on troubling pseudoscience and can discriminate"
Hilke Schellmann tried the myInterview tool to check her "hiring score":
  • Honest interview in English: 83%
  • Reading a random wikipedia page in German: 73%
  • Getting a robot voice to read her English: 79%

"Our success, happiness, and wellbeing are never fully of our own making. Others' decisions can profoundly affect the course of our lives...

Arbitrary, inconsistent, or faulty decision-making thus raises serious concerns..."

- Fairness and Machine Learning, Barocas, Hardt, and Narayanan

"The hype is a lie"
Engadget
The best thing you can do is actually know things,
and that's what this course is about.