053 ♓ Skipjack ♓ Tuna

In the upcoming election on the third of March the citizens of Chuuk state will be asked to vote on whether to secede from the Federated States of Micronesia. Those who favor secession have a number of reasons for seeking separation. One the reasons the secessionists have cited is a desire to retain the full tuna licensing fees for fish caught in the waters of the FSM. At a recent presentation by the Chuuk Political Status Commission, members of the national government noted that the bulk of the tuna is caught in the equatorial waters of Pohnpei and Kosrae state, primarily the waters around Kapingamarangi. While state level catch data is not available, charts from the Western and Central Pacific Fisheries Commission (WCPFC) provide some information on how much fish is caught by location. That data supports the statements made by the national government - roughly only three percent of the fish caught in the waters of the FSM appear to be caught in the waters of Chuuk state.

This election year midterm uses skipjack tuna catch data estimates in tonnes made from a chart of total catch 2007-2009. Use the tonnes of skipjack to answer the following questions. Skipjack tuna has the Latin name Katsuwonus pelamis and is known locally as angaraap (Chuuk), kasuo (Pohnpei), katsuo (Kosrae), and garngab (Yap).

LocationTonnes Skipjack
Yap west13000
Yap outer island16000
Pohnpei 13000
Pohnpei Kapinga west152000
Pohnpei Kapinga east152000
Kosrae southern waters152000
  1. For the tonnes of skipjack the level of measurement is: _
  2. Calculate the sample size n: _
  3. Calculate the minimum (zeroth quartile).
  4. Calculate the first quartile.
  5. Calculate the median (second quartile).
  6. Calculate the third quartile.
  7. Calculate the maximum (fourth quartile).
  8. Calculate the interquartile range: _
  9. Calculate the range: _
  10. Calculate the mode: _
  11. Calculate the sample mean: _
  12. Calculate the sample standard deviation sx. Round your answer to a whole number: _
  13. Calculate the sample coefficient of variation CV. Round your answer to two decimal places: _
  14. Calculate the z-score for Kosrae's 2000 tonnes of skipjack. Round your answer to two decimal places: _
  15. If the data is divided into five classes, calculate the width of a single class: _
  16. Calculate the five class upper limits, the frequencies and the relative frequencies for the tonnes of skipjack data. Identify the correct frequency/relative frequency table in the image.
    Class upper limitsFrequency FRel. Freq.

    frequency tables
  17. Identify the correct five class frequency histogram for the data.
    frequency tables
  18. What is the shape of the histogram?

Part two: Paired data

The growth rate of skipjack tuna is a factor in the sustainable yield calculations. The following table reports on the age of skipjack in months and the length in centimeters. Use this data for the paired data questions.

Age (months)Length (cm)
  1. Calculate the sample size n: _
  2. Calculate the slope of the linear regression. Round your answer to two decimal places: _
  3. Calculate the y-intercept of the linear regression. Round your answer to two decimal places: _
  4. Is the relation between the variables positive, negative, or neutral?
  5. Calculate the correlation coefficient r for the data. Round your answer to two decimal places: _
  6. Is the correlation none, weak, moderate, strong, or perfect?
  7. Determine the coefficient of determination. Round your answer to two decimal places: _
  8. Use the slope and intercept to calculate the predicted length in centimeters for 30 months. In the calculation use the unrounded slope and intercept. Round the final answer to one decimal place: _
  9. Use the slope and intercept to calculate the predicted age in months for a length 21 centimeters.In the calculation use the unrounded slope and intercept. Round the final answer to ONE decimal place.

Supporting data:
Pacific skipjack distribution
Pacific skipjack distribution


Money values: http://www.fsmopa.fm/files/onpa/Final%20Audit%20Report%20No.%202012-03%20Compressed%20Version%20in%20MB%20size%281%29.pdf
For the past three years, the revenue generated from fishing rights was approximately $20 million in 2009, $17.7 million in 2010 and $ 18.8 million in 2011. Another crucial benefit of tuna industry to the FSM economy is the employment it provides


Main landing places

Landing sites for industrial tuna fishing vessels exist on the principal islands of each of four states of the Federated States of Micronesia (FSM), but as most of the vessels are based in Pohnpei, most offloading occurs there. Small-scale commercial fisheries are also focused on the population centres in each state, while subsistence fishery landings are scattered throughout the country.

Estimated landings by principal site (tonnes)

Offshore Locally-basedCoastal CommercialSubsistenceTotal
Kolonia (Pohnpei)200017006504350
Weno (Chuuk)25020005002750
Colonia (Yap)2008005001500
Lelu (Kosrae)50200250500