# Frequency Distribution, Mean and Standard Deviation

Please see attached file for full problem description.

Use the data set collected in a) to do the following.

1. Group the data into at least 10 different classes and create a frequency distribution table for the data set, and graph the histogram of the data set; Make an educated guess about the mean, standard deviation, and make comments about whether the shape of distribution may be considered a Bell curve (Normally distributed).

2. Calculate the summary measurements, mean x and standard deviation s for the data set the "Descriptive Statistics" package in MS Excel.

3. Count the number of measurements in the intervals x ± s, x ± 2s, and x ± 3s. Express each count as a percentage of the total number of measurements. Apply Empirical Rule to discuss whether the conclusion about the shape of the data set distribution give in 1) seems correct.

4. Superimpose the Normal distribution line chart with Mean and standard deviation from 2) onto the relative Frequency bar chart of the data set. Further discuss the shaper of the data set.

The completed project report should be created in One Microsoft Excel file. The report should include

? (Sheet 1. name it Cover Sheet) A cover page with a title of your project (you select), and student names of the group.

? (Sheet 2. name it Data) A detailed discussion about objective of you analysis and the how, when, and where you collected your data. Discuss why the data you collected is representative. Provide the raw data in this sheet.

? (Sheet 3. name it Data Analysis) This sheet contains answer to question 1-4.

Give clear explanation about the class range selection, as well as the generated Table(s) and Chart(s).

#### Solution Preview

a) Data collection

? Collect a sample of data with at least 50 observations.

I put the data in an Excel spreadsheet.

b) Data Analysis

Use the data set collected in a) to do the following.

1. Group the data into at least 10 different classes and create a frequency distribution table for the data set, and graph the histogram of the data set; Make an educated guess about the mean, standard deviation, and make comments about whether the shape of distribution may be considered a Bell curve (Normally distributed).

I made the frequency distribution by sorting the data, setting 13 class intervals of width 2, and counting the number of scores in each class. I used that information to make a histogram. (Note: I chose 13 intervals because the instructions said to group the data into at least 10 classes. To have at ...