### What is the Meaning & Definition of Variable

The variable term is used when you want to mean that some things, situations and it even if people have a recurrence to the instability and inconstancy. This broadly and very informal of course, but if we get a little more serious and formal, say that variable is what we said and is a symbol that represents an item not specified or identified from a given set. This same set is called a universal set of variable and each Member of that group is a value of the variable.
For example, and in order to make it more clear, 'X' is a variable of the next universe 2, 4, 6, 8, whereby x will have any of those values and may be replaced by any less than 9 par value.
In this case and as we saw through the example, the variable is an element of a formula that can be replaced or purchase any value within that universe; out of it, obviously, this will be impossible. Meanwhile, there are different types of variables, we have subsidiaries and independents on one side and on the other with the qualitative and quantitative. The first are which will depend on the value that assume the other variables and the latter are those that may experience changes per is in its value and affect the other. For example, in a model in which the price of an object is a weight, the number of objects that I consider is an independent variable, while the final price, to link up directly with the amount of objects, will be the dependent variable. In this simple variant, the independent variable "four objects" you shall be the dependent variable "four pesos".
On the other hand, qualitative variables express qualities, characteristics, or different modes and the quantitative set out only in numbers. Thus, as different parameters such as price, blood pressure, the number of legs of an animal or the number of parts of a motor are quantitative variables. On the other hand, the hair color, brands of automotive dealership, the authors present in a library or a local stock components are qualitative variables. In this regard, it is interesting to note a special type of qualitative variable, which is called a dichotomous variable: "Yes" or "no", only 2 possible options. When you want to analyze with statistical techniques some varying more or less complex, a widely used strategy is to replace a dichotomous variable by a numeric code; the "Yes" becomes "1" and "no" becomes "0". This trick has expanded so that, when we stumbled upon qualitative variables with more than 2 options, it is possible your numeric data conversion and, in that way, be able to extract information. The best example is the replacement of the months of the year by its order in the calendar: "January" (qualitative variable) is "1" (numeric variable)... and thus to "December" which becomes "12".
Through the analysis of variables have been made numerous advances in human knowledge areas as diverse as mathematics, economics, geology, archaeology, and the health sciences. Therefore, the knowledge of these "companions of route" of every day makes it easy to understand better the world that surrounds us.
Article contributed by the team of collaborators.