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B. Where Does Data Come From?


๐ŸŽฏ Learning Goals

By the end of this lesson, you'll be able to:

  • โ—‹ You understand where data comes from
  • โ—‹ You know how to find open data
  • โ—‹ You can make simple data yourself

Where Data Comes From

1. Data You Make Yourself

The easiest way! Record it yourself.

๐Ÿ“ Example: My Study Hours for a Week

# Record study time every day for a week
study_hours = [2, 3, 1, 4, 2, 0, 3]
days = ["Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"]
Day Mon Tue Wed Thu Fri Sat Sun
Time 2 3 1 4 2 0 3

Data you can make yourself:

  • Your classmates' heights/weights
  • A week of allowance spending
  • How much water you drink in a day
  • Game score records

2. Survey Data

You ask Questionlots of people and gather it up!

๐Ÿ“‹ Example: Surveying Classmates' Hobbies

"What's your favorite hobby?"

Hobby Responses
Gaming 12
Sports 8
Reading 5
Music 5
hobbies = ["Gaming", "Sports", "Reading", "Music"]
counts = [12, 8, 5, 5]

3. Open Data (Open Data)

Anyone can use it for free โ€”that's open data!

๐ŸŒ Why do people make data public?

  • Government: to share information transparently with the public
  • Companies: to support research and innovation
  • Research institutes: to advance science

Useful Open Data Sites

๐Ÿ‡ฐ๐Ÿ‡ท Korean Open Data

1. Public Data Portal (data.go.kr)

A government-run official data portal

  • Many fields, like weather, traffic, environment, and education
  • Free to download
  • Provides real-time data via API

Examples of data you can find

  • Seoul fine-dust levels
  • Nationwide school information
  • Population by region
  • Bus/subway operation info

2. Statistics Korea KOSIS (kosis.kr)

Korea's official statistics info

  • Population, economic, and social statistics
  • Number of students by school level
  • Birth/death statistics by year

3. Seoul Open Data Plaza (data.seoul.go.kr)

Seoul-related data

  • Ttareungi (public bike) usage stats
  • Seoul subway boarding/alighting counts
  • Population statistics by district

๐ŸŒ Global Open Data

1. Kaggle (kaggle.com)

A data science competition platform

  • Fun datasets from all over the world
  • Titanic survivor data
  • Pokรฉmon stats data
  • Movie rating data

Recommended datasets for beginners

  • ๐ŸŽฎ Video game sales data
  • ๐Ÿฟ Movie info data
  • โšฝ Soccer player stats

2. Our World in Data (ourworldindata.org)

World issuesdata about

  • Climate change
  • World population
  • Health and medicine

3. Google Dataset Search (datasetsearch.research.google.com)

A search engine just for data

  • Search for data by keyword
  • Connects datasets from around the world

Simple Data Examples

Data You Can Use Right Away in Class

Fruit sales data

# Fruit names and sales
fruits = ["Apple", "Banana", "Orange", "Grape", "Strawberry"]
sales = [45, 30, 25, 40, 55]

Monthly temperature data (Seoul)

# Seoul monthly average temperature (ยฐC)
months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun",
          "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
temperatures = [-2, 0, 6, 13, 18, 23,
                25, 26, 21, 14, 6, -1]

Our class's score data

# Our class's average score by subject
subjects = ["Korean", "Math", "English", "Science", "Social Studies"]
class_average = [82, 78, 85, 80, 83]

Athlete data

# Soccer players' goal counts
players = ["Son Heung-min", "Kim Min-jae", "Lee Kang-in", "Hwang Hee-chan"]
goals = [23, 2, 8, 12]
assists = [7, 1, 10, 5]

Ideas for Using Data

๐Ÿ’ก Project Ideas

1. Survey Your Class

  • Survey of favorite subjects/foods/games
  • Survey of commute time/method
  • Distribution of birthdays by month

2. My Records

  • A week of exercise time
  • A month of allowance spending
  • Daily smartphone usage time

3. Use Open Data

  • Fine-dust changes in your neighborhood
  • Comparing your favorite game characters' stats
  • K-pop group album sales

๐ŸŽฏ Quiz

Quiz: Open Data
Which of the following is Open Data (Open Data)which statement is correct?
Show Answer

Answer: B) Anyone can use it for free

Open data is:

  • โœ… Anyone can access it freeof charge
  • โœ… You can download and Usage it
  • โœ… Use it for research, learning, and projects Use it

You can find lots of data on the Public Data Portal (data.go.kr)!


Quiz: Data Sources
What's the best way to find out "your classmates' favorite colors"?
Show Answer

Answer: A) A survey

Data unique to your own class has to be surveyed yourself!

  • Make a questionnaire
  • Ask your classmates
  • Gather and organize the responses

Open data is used when you're looking for general information.


Practice: Make Your Own Data

โœ๏ธ Practice: Make a Data Collection Plan

Fill in the blanks below to make your own data collection plan!

  1. Topic: _______ (e.g., favorite snack)
  2. Target: _______ (e.g., my classmates)
  3. Question: _______ (e.g., What's your favorite snack?)
  4. Expected items: _______ (e.g., chips, ice cream, tteokbokki...)

๐Ÿงฉ Key Takeaways

What you learned in this lesson:

Source Description Example
Collect yourself I record it Study time, exercise records
Survey Ask other people Survey of favorite subjects
Open data Data provided for free Weather, population, traffic

Useful sites:

  • ๐Ÿ‡ฐ๐Ÿ‡ท Public Data Portal: data.go.kr
  • ๐Ÿ‡ฐ๐Ÿ‡ท Statistics Korea: kosis.kr
  • ๐ŸŒ Kaggle: kaggle.com

Preview of the Next Lesson

In the next lesson, we'll learn data and visualizationLearn what it is!