Data Types

Data Types:

  • Qualitative Data: Categorical Variables
    • Nominal Data: There is no order or level to data. E.g. name.
    • Ordinal Data: Data is meaningfully ordered. E.g. quality(from bad to good).
  • Quantitative Data:
    • Continuous: uncountable values, or those that can take on infinite values.
    • Discrete: finite or countably infinite variables

Data Type Structures:

  • Structured data:
    • tabular: In tabular data, everything is arranged in columns and rows. Every row have the same number of column (except for missing value, which could be substituted by "N/A". The first line of tabular data is most of the time a header, describing the content of each column.
    • spreadsheet
  • Unstructured data: E.g. images, texts, sounds, and videos

Identifying data structures and types of each variable is part of Exploratory Data Analysis (EDA) and mixed types or other issues is resolved in Data Preparation process.