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Data and its types

The data have been stored in different types in various applications based on the needs. The popular form of the data is in tabular form such as given below.


The tabular data shown above has few rows and columns. The each row represents each record. The each column represents the different attributes of each record. 

The record is also referred as Sample, Instance, Case etc.

The attribute of a record is also referred as Variable, Field, Feature etc.

The attribute of the record shall be captured in different types. They are

Nominal - Provides distinguishable information such as Student ID, Gender etc

Ordinal - Provides comparable information such as Score, Grades etc

Interval - Provides interval information such as Dates etc

Ratio - Provides ratio information such as Age, Height etc

The properties of attribute values shall be

  • Distinctness [ Equal to or Not Equal to ]
  • Ordering [ Greater than or Less than ]
  • Addition/Subtraction
  • Multiplication/Division

The attributes of the record shall possess the properties based on its type.

Nominal  - Distinctness

Ordinal -  Distinctness & Ordering

Interval - Distinctness, Ordering & Addition/Subtraction

Ratio -  Distinctness, Ordering, Addition/Subtraction & Multiplication/Division

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