STAT 200 Fall 2015 QUIZ - 1

STAT 200

Fall 2015

Quiz #1

There are 31 participants in a special high-adventure camp at Goshen Scout Camp last September. Following is a list of the age of the participants.

16, 18, 13, 24, 17, 17, 18, 14, 14, 16, 14, 20, 22, 21, 15 11, 13, 26, 27, 13, 16, 17, 17, 14, 19, 15, 17, 16, 19, 19, 28

1.      (6 points) Prepare a frequency distribution of the participants' ages with a class width of 2 years, and another with a class width of 5 years.

2.      (5 points) Construct a histogram of the participants' age with a class width of 2 years and another with a class width of 5 years. What can we say about the choice of class width?

3.      (5 points) Give a 5-number summary of the ages of the participants, and construct the corresponding box-plot.

 (For Questions 4 & 5) Below please find a hypothetical (imaginary) data set for the enrollment number in our three statistics classes over the past few years. Please note that STAT 225 was not in existence until the fall of2006.

4.      (7 points) There are many graphical formats to illustrate a given data set. However, some formats are better than others in the sense that they convey important and relevant information in the given data set. For the given data set, pick the most appropriate graphic format to present the above data set, and plot the given data. Feel free to process the data set and/or include additional information you can deduce from the data set that you think can be useful to make your point.

5.       (6 points) At times, there may be unwarranted features in the plots you come up with, even though they are true representation of the given data. We may call that data noise, and it will distract us from conveying essential information in the data set. Do you encounter this situation in your plot? If so, what would you do to minimize distractions without misrepresenting the data?

 (For Questions 6, 7, & 8) I have a collection of 5 ancient gold coins. Their weights, in ounces, are 23.1, 18.6, 33.5, 12.4, and 27.1.

6.      (2 points) What is the mean weight of my ancient gold coins?

7.      (2 points) How do you consider this collection, a population or a sample? Why?

8.      (2 points) What is the variance and standard deviation in weight of my coin collection?