What is data journalism? Cody Winchester, IRE/NICAR @cody_winchester

Data journalism, CAR, “quantitative journalism” Using computers to help you solve reporting problems CAR = Computer-Assisted Reporting Focusing on numerical evidence, not just anecdote, to tell stories Common pattern: Analyze data to find trend/test hypotheses, use anecdotes to help tell story Using data to investigate leads almost always results in a better story than “I wonder if there’s a story in this data”

Buzzfeed/BBC: Tennis match-fixing BuzzFeed News began its investigation after devising an algorithm to analyse gambling on professional tennis matches over the past seven years. It identified 15 players who regularly lost matches in which heavily lopsided betting appeared to substantially shift the odds – a red flag for possible match-fixing. Analysis methodology and code

ProPublica/Consumer Reports: Insurance Our analysis of premiums and payouts in California, Illinois, Texas and Missouri shows that some major insurers charge minority neighborhoods as much as 30 percent more than other areas with similar accident costs.

Bristol Herald Courier: Mineral lease payments Of about 750 active individual accounts in escrow, between 22 percent and 55 percent received no royalty payments during months when the corresponding wells produced gas over an 18-month period, a Bristol Herald Courier investigation has found. (2010 Pulitzer Prize Winner in Public Service)

Omaha World-Herald: Prison sentences A World-Herald investigation showed that Nebraska prison officials — using a flawed formula to calculate sentences — had wrongly released or were set to release dozens of prisoners years before their sentences were supposed to end.

What do data look like? XLS / XLSX CSV / TSV / TXT JSON DBF XML

What do data look like?

What do data look like?

What do data look like?

What do data look like?

The process Obtain data → clean/verify/prep data (80% of the work) → analyze data → report/visualize

A set of data is like a human source You ask it questions You follow up You understand how it knows the answers

What tools can you use to ask data questions? Spreadsheets (Excel, Google Sheets, OpenOffice, etc.) Database managers (Access, SQLite, MySQL, Postgres, etc.) Programming languages (R, Python, etc.)

Data journalism: What it can do for you Helps you ask better questions, report more efficiently Quantifying information means you can visualize it for your audience Gives your journalism more authority Working with structured data makes watchdog reporting easier Context for breaking news coverage

Data journalism: What it can’t do for you Doesn’t replace shoe-leather reporting Data = always messy Great for the what, not the why Treat data like any other source: with care, skepticism and curiosity Understand how it’s collected and kept Get the methodology Data are created by humans Humans make mistakes Humans have agendas