All Fresh Seafood is a wholesale fish company based on the east coast of the U.S.  Catalina Offshore Products is a wholesale fish company based on the west coast of the U.S.  Table #9.2.5 contains prices from both companies for specific fish types ("Seafood online," 2013) ("Buy sushi grade," 2013).  Data is in following table:  Fish All Fresh Seafood Prices Catalina Offshore Products Prices Cod 19.99 17.99 Tilapi 6.00 13.99 Farmed Salmon 19.99 22.99 Organic Salmon 24.99 24.99 Grouper Fillet 29.99 19.99 Tuna 28.99 31.99 Swordfish 23.99 23.99 Sea Bass 32.99 23.99 Striped Bass 29.99 14.99 Do the data provide enough evidence to show that a west coast fish wholesaler is more expensive than an east coast wholesaler?  Test at the 5% level.   (i)  Let μ1 = mean wholesale prices from east coast fishery.  Let μ2 = mean wholesale prices from west coast fishery .  Which of the following statements correctly defines the null hypothesis HO? A.  μ1 − μ2 > 0  (μd > 0) B.  μ1 – μ2 = 0  (μd = 0) C.  μ1 – μ2 < 0  (μd < 0) D.  μ1 + μ2 = 0 Enter letter corresponding to correct answer    (ii)  Let μ1 = mean wholesale prices from east coast fishery.  Let μ2 = mean wholesale prices from west coast fishery .  Which of the following statements correctly defines the alternative hypothesis HA? A.  μ1 − μ2 > 0  (μd > 0) B.  μ1 – μ2 = 0  (μd = 0) C.  μ1 – μ2 < 0  (μd < 0) D.  μ1 + μ2 = 0 Enter letter corresponding to correct answer  (iii)  Enter the level of significance α used for this test: Enter in decimal form.  Examples of correctly entered answers:  0.01    0.02    0.05    0.10

Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...