Statistics for Decision Making

Statistics for Decision Making

The Role of Sampling in Statistics

In statistics , a sample is a section of the subject chosen for a study . In most cases sample will to be taken because a given subject area to be researched has a large number of participating population If a decision is made to make some kind of a study on a given subject , a population for example , it is easy to take a sample and work with the sample to arrive at whatever is intended on the outset , which in most cases

is to make a statistical calculation that could be about the samples opinion on a given subject matter , such as voting for example The reason why taking samples is important is because of the large number of the population or groups that will be targeted . Such a process of obtaining information to infer and extrapolate an outcome from a collected data goes by the name known as sampling . There is always effort exerted to avoid bias when taking samples , which means the outcome of the finding will have to be unbiased as much as possible and that is when the accuracy of the data could be relied upon . [1]

If someone wants to make a certain study that pertains to women and if the sample is taken only from women who are working in an office environment , it will miss its target , and will not be representative because the bigger population of women might not be working in the office . There are stay-at-home moms , there are those who are working in various fields that do not involve working in an office environment there are those who could be unemployed and cannot be included in the sample that will be taken from offices . The solution for this problem is to make the sample random or a probability sample because it will be a better representative of the diverse women population and those that are not working in the office could also be included

When dealing with samples the first key aspect to pay attention to is external validity , which focuses on the approximate truth of the conclusion or how the conclusion will be applicable to other subjects that are in different places , and how it would hold if used at a different time . There are two known general approaches to arrive at a conclusion through a finding made by conducting a research . The first one is sampling model where like it was mentioned , it is possible to target a subject or a population and take a sample to conduct the required research and most of the time the finding could be relied upon and could be used to arrive at a conclusion . But it is possible label the sample as biased , which means no matter how careful the process had been , there is a possibility of a bias . [2]

The other approach called Proximal Similarity Model that was suggested by Donald Campbell can be used to take varied samples...