Monday, 1 August 2011

What is data analysis and inference?

Statistical sampling methods have been the new discovery in the fields of survey and data analysis. Unlike earlier times where sample analysis was done by collecting data from the entire population, today, random sampling have become the new face of data analysis. Sampling methods such as these are used to extract key information regarding something and helps the researcher to draw inferences based on them. 

A data analysis also includes quantitative modeling of historical data to determine the future behavior of the population and to estimate profits and losses. The results conjectured from these sample analysis very much depends on the researcher and on the methods which he used to carry out the survey. A well planned and designed analysis can be very less time consuming and may yield precise and accurate results. It also makes the job of the researcher much easier when it comes to the drawing of inferences. 

A statistical inference in basically done to validate the assumption or the hypotheses made by the researcher. Inferences are drawn to ensure the success or failure of the survey done. Inferences can be of different types, such as the ‘Bayesian inference’ or the frequentest inference, both of which are the results of the data analysis done.

Sample survey design and analysis

A survey is basically done on a huge number of populations to prepare a statistical data of something. A population may be a group of people in a business organization, in households or even certain parts of equipments. Survey always precedes a detailed analysis of anything. By collecting people’s opinions, the person prepares a sample analysis to be evaluated later. A survey can be designed in variety of methods depending on the choice of the researcher. One may opt for a face-to-face interview, or may go for postal interviews. Web questionnaires, telephone and E-mail questionnaires are also other options that one may seek for. 

It very much depends on the target population as to how a question should be designed. Whether it should complex, ambiguous, vague, should it include embarrassing questions, hypothetical questions or questions regarding their choices? The sample analysis should be done on a scale and one should have the discretion to agree or disagree to it. The questionnaire should be done by keeping similar types of questions and factual questions together. A sample analysis is made to reduce the risk of any faults. The researchers infer a lot of facts about the opinion of the mass form these surveys.