Week 2 Notes - Course Introduction

Published

September 15, 2025

Algorithm

  • set of rules to solve problems
  • issues of data-driven policy-making: what is true for a group of people is not always true for individuals

Difference between data science and data analysis

  • data science: focus on algorithms/methods development
  • data analytics: application

Machine learning and AI

  • Machine learning: classification&prediction learn from data
  • AI: adjust and improve across iterations

Accidental data

  • get data from open-source sources like social media platforms, instagram

Data analytics is subjective

  • data cleaning
  • data coding
  • data collection
  • interpret results
  • what variables to put in the model

Decennial Census & American Community Survey (ACS)

  • Decennial Census
    • for everyone, full sample
    • 9 basic questions
    • constitutional requirement
  • American Community Survey
    • 3% surveyed annually
    • detailed questions
    • 5-yr estimates are more reliable