Stat 130 Written Homework Chapter 2 Solutions PDF

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Stat 130 Written Homework Chapter 1 SOLUTIONS.pdf...

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STAT 130 Written Homework Chapter 2 1. A group of people were asked how many books they read in the last year. The results were: 0,0,0,0,0,0,1,1,1,1,2,2,2,3,3,4,4,5,6,6,7,8,12,15. a. Compute the mean for this data. (0+0+…..+15)/24 =83/24 = 3.46

b. Compute the median for this data. There are 24 observations, so the average of the 12th and the 13th observation, which is (2+2)/2 = 2

c. In Written Homework 1, you made a histogram from this data and it was skewed to the right. When you compare your answers to a and b is that consistent with what you would expect for skewed data. Briefly explain.

Data is skewed right, so I expect the mean to be larger than the median.

d. The standard deviation for the data is 3.95. What does this value tell you?

It tell me approximately how far the data points are from the mean on average.

e. Compute the first and third quartiles (Q1 and Q3). Q1 is the median of the first 12 numbers: (0+1)/2 =.5 Q3 is the median of the last 12 numbers: (5+6)/2 =5.5

f. Compute the Interquartile Range IQR is Q3-Q1 = 5.5-.5 = 5

g. Compute the upper and lower fence and determine if there are any outliers in the data. Lower Fence: Q1-1.5*IQR = .5-1.5*5 = -7 Upper Fence: Q3+1.5*IQR = 5.5+1.5*5 = 13 15 is beyond the fence, so is an outlier.

h. Sketch a boxplot for the data....