PROJECT FOR Statistics
(Project counts for 65 points)
Project Due Dates
1. Determination of type of data to be collected, and a statement as to what the mean
value or proportion is expected to be. This mean value or proportion will be
considered to be a true population mean value, μ, or proportion, P, and it will be
your null hypothesis. Complete project with data analysis.
2 Determine the sample size required for a given margin of error. Even though the
sample size for this project will be at least 30 data points (for mean values),
calculate the required sample size. Calculate the sample size for a 90% and a
95% confidence interval. To do this, E and σ will have to be estimated. Think
about the maximum error of estimate (E) that is desired and the amount of
variability you expect to see in the data. For proportional data, only E has to
be estimated. Three percent is a typical value for E.
Elements of the Project
1. Collect the desired data (at least 30 samples). Describe when, where, and how the data
was obtained. Proportional data typically has a couple hundred values.
2. For mean values, calculate the mean, median, and mode for the sample set. Also
determine the variance and standard deviation for the sample set. For
proportional data, state the proportion and sample standard deviation.
3. For mean values, plot a frequency distribution histogram for the data. This will
require choosing the number of classes desired and determining the class width.
Show where the mean, median, and mode occur in the diagram. State whether the
distribution is approximately normal or if it appears negatively or positively
skewed. For proportional data, present a pie chart.
4. Using the sample standard deviation, use the formula for Confidence Limits and
calculate a 90% and 95% confidence interval of the mean.
5. Using the z or t test, make a decision to reject or not reject the null hypothesis.
Do this for both a 90% and a 95% level of significance. This could be a one tail
or a two tailed test.
6. Write a report corresponding to the above numbers. Present the report in a folder,
and be prepared to discuss in class. Was the null hypothesis accepted or rejected?