Opinion polls as a way of sampling

Today mention an error that is usually found frequently in the literature on surveys and opinion polls.
The same is to confuse all the surveys for opinion polls or social surveys. If we wish to clarify what is a survey, or provide a definition, we must make it clear that by no means something that applies to people necessarily.
In fact, the survey is a technique of data collection (some might question how far the data are "collected" as one who takes something that's already been out there and are not created, at least to some extent by those who do research, but that is another problem that will address later) that derives or is an application of the sampling procedure.
Specifically is the use of certain standardized and validated procedures under which the research takes information on a representative sample of a population or universe, as is usually called the total haw investigated.
It is clear that the purpose of such research procedures is to improve our insight of some phenomenon, say a good explanation.
One can conduct a survey in which sample is selected books from a library upon which a questionnaire is completed in some information, because what matters is that the procedure and representative sample.
This, as already mentioned, results from the application of the mathematical theory of probabilities to the investigation of phenomena, whether or not social.
A sample survey differs from a census in which it is to administer a questionnaire to all people concerned, while the survey is always applied to a sample, the best representative.

Opinion polls: history and some methodological details

Opinion polls are not, in fact nothing but a way of investigating. In particular, are a method, or a set of methods or techniques, aimed at collecting information about some aspect of social reality. Properly understood, then as a research strategy of social phenomena, the poll is fairly recent, then use systematic and controlled (and successful) dates from the interwar period of the twentieth century.
The practical reasons that led to its development (something quick) and implementation were, naturally, in war, economic and largely related to the profound social and political changes that were operated on is this particular period. However, beyond the needs of specific practices that gave rise, the survey would not have been possible without the theoretical and methodological developments that support and, previously, had not taken place. As noted, the survey is provided, among other things, the application of certain mathematical procedures to obtain information on social reality. Here it should be noted the importance of American sociology, as embodied in major theorists and researchers such as Paul Lazarsfeld and the famous George Gallup.
In the next posting will show how, in the American case in particular, individual ballots and certain developments in social psychology set the stage, so to speak, the emergence of the survey, the opinion poll as we know it today, meaning a tool of public record.
Let us note finally that, as background music for all these reasons and background, there has always been associated with research through opinion polls what Karl Popper called the old dream of prophecy: the desire to know what happen. It is not necessary to know what a survey or to properly take this factor into account, but if we arrive at an understanding of the case, it should not be olivdar.
Many are those who do not mind, and many people mistakenly believe have achieved.

Polietapic sample desing

What is a polietapic sample design?
A sample design polietápico is a type of design research project to collect data from a survey which is divided into various stages of planning and implementation.
These stages cover various criteria that are deployed to reach the final sample, or to individuals that will finally answered the survey.
Let us remember that a sample is a part of a specific population or universe (e.g. a country or a city citizens) is selected to obtain information that will be generalized to the whole population with some margin of error.
As a result, when according to rigorous methodological guidelines, the sample will be representative of this population.
To make this happen, the universe will be successively divided according to different criteria to reach the people you select.
For example may split the provinces or States of a country and select some rightly gaming, dodging, and then in selected provinces applied with a proportionality to the population parameters selection criterion.
If there are 10% of high socio-economic level in the population, determining the sample shall be about that value.

Opinion surveys

Opinion surveys
Surveys of public opinion and policy surveys.
Methodology, theory and analysis of public opinion polls.