| When use correctly, statistical data can be used | | | | cause-and-effect relationships, how one thing |
| to improve an array of areas from efficiency, to | | | | affects another. |
| lead time, and profit. But in order to make | | | | - Observational study - Observational studies also |
| improvements you need to know how the data | | | | try to discover the cause and effect relations, but |
| has been collected initially. This article is about | | | | unlike experiments, they are not able to control |
| Statistical data collection methods. | | | | how subjects are assigned to groups. |
| There are four main Statistical data collection | | | | As it was already pointed out, every method has |
| methods: | | | | its own pros and cons, so one must be able to |
| - Census | | | | know and make a decision regarding which |
| - Sample survey | | | | method should be applied in a given situation. |
| - Experiment | | | | There are three factors that should affect this |
| - Observational study | | | | decision and they are - resources, generalizability, |
| Each of these methods has it's own set of | | | | causal inference. |
| advantages and drawbacks, that's why one must | | | | If resources are the main factor, then obviously |
| be aware of all their characteristics to be able to | | | | with such a large population, a sample survey has |
| choose the right method according to the | | | | an advantage over census. If the sample survey |
| individual situation. Here is a brief definition of each | | | | is well designed, then it can definitely provide |
| method: | | | | results that are really close to the actual figures |
| - Census - A census is a case study that acquires | | | | (high level of accuracy), and it will be done in a |
| data from every population member. For the | | | | quicker and cheaper manner, requiring less man |
| majority of cases, a census is not practical, due | | | | power than a census. |
| to the large amount of time and cost required to | | | | Generalizability stands for applying findings from a |
| conduct it. | | | | sample study to a larger population. Generalizability |
| - Sample Survey - A sample survey is a case | | | | requires random selection. In case the participants |
| study that obtains data only from a subset of the | | | | in a study are randomly selected from a larger |
| entire population, not every member, as oppose | | | | population, it is appropriate to generalize study |
| to Census, so it's much more practical and | | | | results to the larger population, otherwise it might |
| efficient to carry out, but the results might not be | | | | provide accurate results. |
| that accurate. For best results using this method it | | | | Statistical data collection methods are essential for |
| may be appropriate sub-categorize your target | | | | sustainable economics, social and environmental |
| group and take a sample set from each | | | | development. We are living in the 'Information |
| sub-category. A basic example would be different | | | | Age' where certain data sets are growing in size |
| ethnic groups. | | | | and complexity, reaching massive proportions, |
| - Experiment - The experiment is a controlled | | | | that's why such data collection methods are so |
| study in which researchers try to understand the | | | | important. |