MS 150 Statistics fall 2007 test one • Name:

A study of the length in centimeters of Cephalopholis argus [English: Peacock hind or blue-spotted grouper, Kosraen: Kalsrik, Mortlockese: Sawei, Mwoakillese: Widir, Pohnpeian: Mwoalusulus, Woleaian: Hali] found in the markets on Pohnpei from January to May 2006 was done by Kevin Rhodes, M. Tupper, Scotty Malakai, Don Jack, Clement Wichilmel, Richard Ben, and Kirino and Anson Olpet. The data is based loosely on this work.

1. __________ What is the level of measurement?
2. __________ Find the sample size n.
3. __________ Find the minimum.
4. __________ Find the maximum.
5. __________ Find the range.
6. __________ Find the mode.
7. __________ Find the median.
8. __________ Find the sample mean x.
9. __________ Find the midrange.
10. __________ Find the sample standard deviation sx.
11. __________ Find the sample coefficient of variation CV.
12. __________ If this data is to be divided into five bins, what is the width of a single bin?
13. Determine the frequency and calculate the relative frequency using five bins (classes, intervals). Record your results in the table provided.

    Bin upper limits	Frequency F	Relative Frequency
    Sums:

14. Sketch a frequency histogram of the data, labeling your horizontal axis and vertical axis as appropriate. Use the back of this sheet if necessary.
15. __________ What is the shape of the histogram?
16. z = __________ Use the formula z = (x - x)/sx to find the z-score for a Cephalopholis argus that is 32 cm long.
17. _________________ Is a 32 cm long Cephalopholis argus an ordinary length or an unusual length for this fish in the markets of Pohnpei?
18. According the study, Cephalopholis argus first reaches sexual maturity and can reproduce when it reaches a length of 22 cm. The fish can grow up to 60 cm in length. Based on the mean above, are the fishermen of Pohnpei catching older, larger fish or younger, less mature fish? What does this suggest about the condition of this fishery?

Statistics • Lee Ling • COMFSM