What is quantitative variable?

What Does quantitative variable Mean

The symbol that appears in propositions, algorithms, formulas and functions and that takes different values ​​is called a variable . According to their characteristics, it is possible to distinguish between different classes of variables.

The quantitative variables are those that adopt numerical values (ie, numbers). In this way they differ from qualitative variables , which express qualities, attributes, categories or characteristics.
The height of an individual is a continuous quantitative variable.
The quantitative variable according to etymology
It is important at this point that we proceed to know the etymological origin of the two words that give shape to the term in question:

-Variable comes from Latin, specifically derived from “variabilis”, which can be translated as “that can change its appearance”. It is the result of the sum of two components: the verb "variare", which is synonymous with "change of appearance", and the suffix "-able", which is used to indicate possibility.
-Quantitative, for its part, comes from Latin as well and is made up of the union of several elements of that language: “quantum”, which is equivalent to “how much”, and the suffix “-tive”. This is used to come to record a passive or active relationship.
Classification according to type
In the set of quantitative variables, we can also recognize several types of variables. The variables Continuous quantitative can take any value within a certain range. According to the precision of the instrument that performs the measurement, there may be other values ​​in the middle of two values. The height of a person, for example, is a continuous quantitative variable (they can be values ​​such as 1.70 meters , 1.71 meters , 1.72 meters , etc.).
With regard to continuous quantitative variables, we can establish that other simple examples would be the mass of any object or the height of a building.
The number of dogs a person has is an example of a discrete quantitative variable.
The discrete quantitative variables , on the other hand, acquire values that are separated from each other on the scale. In other words: there are no other values ​​among the specific values ​​that the variable acquires. The number of pets a person has is a discrete quantitative variable: a woman can have 2 , 3 or 4 dogs , but never 2.5 or 3.25 dogs . In this case, 2 and 3 are values ​​that the variable is able to adopt, without there being any other possible value in between.

Other examples of discrete quantitative variables can be these:
-The number of children a person has.
-The number of animals that a farmer owns.
-The set of vehicles that exist in a dealer.
Uses and graphic representation of quantitative variables
Both types of quantitative variables can be combined in a survey or an interview . The job applicant can be asked how much he weighs (continuous quantitative variable) and how many children he has (discrete quantitative variable).
In addition to all the above, it is important to know another series of interesting data about quantitative variables, such as the following:
-As a general rule, when it comes to graphing them, we choose to make use of integral diagrams and differential diagrams, which are what they use to show the so-called relative frequencies.
-In the same way, you can also resort to using what are bar diagrams.

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