# Statistics and Sample Size

Business Problem Paper and Optional Presentation

a. Clearly define the dependent and independent variables that are the focus of the team's study. The dependent variable is the variable whose value is the result or is a function of the control or independent variables.

b. State the null and alternative hypotheses and the theories that support these hypotheses that will be tested. You should also present the methodology that will be used to test these hypotheses.

c. Clearly define all primary and secondary data sources.

d. Compute the sample size required for the project and provide clear support for the criteria used to arrive at this figure.

e. Describe how you selected and produced your samples. Specifically, you must state how the data was selected, discuss a final plan or methodology to collect the data, describe the survey instruments that would be used to collect your samples, and indicate the analytical approach and test statistics that would be used to test your hypotheses.

f. Make final recommendations related to defining and explaining the problem and stating the hypotheses that will be tested.

g. Include an appendix for any related data and survey instruments. Additional work may include the analysis of the data, interpretation of the results, testing hypotheses, and recommendations based on this analysis.

My team is responsible for doing a paper on the above. We have chosen a computer company that has recently seen sales hurt because of poor customer service. I am responsible for section D above. Could you provide some direction in computing sample size when addressing a business problem. Thanks.

#### Solution Preview

Please see response attached for best formatting, which is also presented below in part. As a rule of thumb large sample size = 30 which is consider large enough for reliable data. I hope this helps and take care.

RESPONSE:

1. Could you provide some direction in computing sample size when addressing a business problem? Thanks.

Determining sample size is a very important issue because samples that are too large may waste time, resources and money, while samples that are too small may lead to inaccurate results. Most often, the sample size formula is used to compute the sample size needed for a specific business problem.

Let's take a closer look at how the sample size formula is derived, and then at an example applying the sample size formula to compute the required sample size for that specific business problem.

Arriving at the Sample size formula -

In many cases, we can easily determine the minimum sample size needed to estimate a process parameter, such as the population mean .

When sample data is collected and the sample mean is calculated, that sample mean is typically different from the population mean . This difference between the sample and population means can be thought of as an error. The margin of error is the ...

#### Solution Summary

Discusses sample size and examples. Supplemented with an article of how to determine sample size.