The statistics It is a branch of mathematics, which corresponds to the collection, analysis, interpretation, presentation and organization of data (set of qualitative or quantitative variable values). This discipline seeks to explain the relationships and dependencies of a phenomenon (physical or natural).
The English statist and economist Arthur Lyon Bowley, defines statistics as: "Numerical statements of facts from any research department, situated in relation to one another." In this sense, statistics are in charge of studying a certain population (in statistics, set of individuals, objects or phenomena) and / or mass or collective phenomena.
This branch of mathematics is a transversal science, that is, applicable to a variety of disciplines, ranging from physics to social sciences, health sciences or quality control..
In addition, it has great value in business or government activities, where the study of the data obtained allows to facilitate decision-making or make generalizations..
A common practice to carry out a statistical study applied to a problem is to start by determining a population, which can be of various topics.
A common example of population is the total population of a country, therefore, when a national population census is carried out, a statistical study is being carried out..
Some specialized disciplines of statistics are: Actuarial Sciences, Biostatistics, Demography, Industrial Statistics, Statistical Physics, Surveys, Statistics in the Social Sciences, Econometrics, etc..
In psychology, the discipline of psychometry, which specializes in and quantifies psychological variables of the human mind, using statistical procedures.
Statistics are divided into two large areas: edescriptive statistics and einferential statistics, which comprise the eapplied statistics.
In addition to these two areas, there is the mathematical statistics, which comprises the theoretical bases of statistics.
The Descriptive statistics is the branch of statistics that describes or summarizes quantitatively (measurable) characteristics of a collection of a collection of information.
That is, descriptive statistics is responsible for summarizing a statistical sample (set of data obtained from a population) instead of learning about population what does the sample represent.
Some of the measures commonly used in descriptive statistics to describe a data set are: measures of central tendency and the measures of variability or dispersion.
Regarding the measures of central tendency, measures such as the half, the median and the fashion. While the variability measures use the variance, the kurtosis, etc.
Descriptive statistics is usually the first part to perform in a statistical analysis. The results of these studies are usually accompanied by graphs, and they represent the basis of almost any quantitative (measurable) analysis of data..
An example of a descriptive statistic might be to consider a number to summarize how well a baseball batter is performing..
Thus, the number is obtained by the number of hits that a batter has hit divided by the number of times he has been at bat. However, this study will not give more specific information, such as which of those batts have been Home Runs.
Other examples of descriptive statistics studies can be: The average age of citizens living in a certain geographic area, the average length of all books on a specific topic, the variation with respect to the time that visitors spend browsing a Internet page.
The inferential statistics differs from descriptive statistics mainly by the use of inference and induction.
That is, this branch of statistics seeks to deduce properties of a population studied, that is, it not only collects and summarizes the data, but also seeks to explain certain properties or characteristics from the data obtained.
In this sense, inferential statistics implies obtaining the correct conclusions from a statistical analysis carried out using descriptive statistics..
For this reason, many of the experiments in social science involve a group of population reduced, thus by means of inferences and generalizations it can be determined as the population in general behaves.
The conclusions obtained through inferential statistics are subject to randomness (absence of patterns or regularities) but by applying the appropriate methods, relevant results are obtained..
Thus, both the Descriptive statistics as the inferential statistics They go hand in hand.
Inferential statistics is divided into:
It includes statistical procedures based on the distribution of real data, which are determined by a finite number of parameters (a number that summarizes the amount of data derived from a statistical variable).
To apply parametric procedures, for the most part, it is required to previously know the distribution form for the resulting forms of the studied population..
Therefore, if the distribution followed by the data obtained is completely unknown, a non-parametric procedure should be used..
This branch of inferential statistics comprises the procedures applied in statistical tests and models in which their distribution does not conform to the so-called parametric criteria. As the data studied define its distribution, it cannot be previously defined.
Non-parametric statistics is the procedure that should be chosen when it is not known whether the data fit a known distribution, so that it can be a previous step to the parametric procedure..
Likewise, in a non-parametric test, the possibilities of error are reduced by using adequate sample sizes..
The existence of the Mathematical Statistics, as a discipline of statistics.
This consists of a previous scale in the study of statistics, in which they use the theory of probability (branch of mathematics that studies the random phenomena) and other branches of mathematics.
Mathematical statistics consists of obtaining information from data and uses mathematical techniques such as: mathematical analysis, linear algebra, stochastic analysis, differential equations, etc.. Thus, mathematical statistics has been influenced by applied statistics.
Yet No Comments