Warm-upDay of 2.1 to 2.4 Quiz

Create an appropriate visual display and write a few sentences comparing the distributions of the data below:

Number of Hurricanes

1944 – 1969 1970 – 20003, 2, 1, 2, 4, 3, 7, 2, 3, 3, 2, 2, 1, 0, 1, 2, 3, 2, 1, 2,

2,5, 2, 2, 4, 2, 2, 6, 0, 2, 5, 1, 2, 3, 1, 1, 1, 3, 0, 1, 3,

2,3, 1, 0, 3 1, 2, 1, 1, 0, 5, 6,1, 3, 5, 3

Student of the day!Block 1

Student of the day!Block 2

Answers to 2.1 to 2.4 Review1)

2) There are two outliers 24 and 25. First I multiplied the IQRby 1.5 to get 7.5. When I added it to Q3 and subtracted itfrom Q1, there were no numbers in my data set that wereabove Q3 + 7.5, or numbers below Q1 – 7.5.3) Both the mean and the standard deviation would double.4) The student should ask for the mean because it takesoutliers into account.

06.51

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42,3741emod22.39

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More answers to 2.1 to 2.4 Review

5. 6. The mean would decrease. The median and mode would stay the same.

Remaining Answers

8. 0.83 of 240, there is about 2 outliers.9. Min: 4.5 minutes; Q1: 40.5;Median:43.5; Q3: 46.5;Max: 67.5 10. About 22% 11. About the 60-63 category. The last 3 bars

add up to 10 so 230/240 = 95.8%12. The data is unimodal with a large gap between 5 and 33

minutes.

Bingo Review of 2.1 to 2.4Fill in your Bingo Cards!

A B C D E AlwaysTrue

Some-times True

Never True Yes No Stem-

and-Leaf

Histo-gram

Mean Median

IQR Variance Range Skewed Right

SkewedLeft

Uniform Symme-tric

Approx.Normal

Bimodal Categor-ical

Discrete Conti-nuous

Scatter-plot

Relative Frequency

Bingo Review 2.1 to 2.4 (Slide 1)

1. Mickey Mantle played with the New York Yankees from 1951 through 1968. He had the following number of home runs for those years: 13, 23, 21, 27, 37, 52, 34, 42, 31, 40, 54, 30, 15, 35, 19, 23, 22, 18. Were any of these years outliers?

2. What would be the best data display for this information?

Bingo Review 2.1 to 2.4 (Slide 2)3) Sometimes, Always or Never True: The total area under a density curve and above thehorizontal axis is 1.4) The following table gives the results of an experiment inwhich the ages of 525 pennies from current change wererecorded. "0" represents the current year, "1" represents pennies one year old, etc. Describe the shape of the data.

Bingo Review 2.1 to 2.4 (Slide 3)

5) The mean of a set of 150 values is 35, its median is 33, itsstandard deviation is 6, and its IQR is 12. A new set is

createdby first subtracting 10 from every term and then multiplyingby 5.

What other summary statistic, other than the standard deviation, is 5 times greater in the new data set?

6) 1

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xxi

Bingo Review 2.1 to 2.4 (Slide 4)

7) Sometimes, Always or Never TrueIf you added 25 to every value in the dataset, thestandard deviation will change.

8) What would be the shape of a histogram displaying the results of 1000 repetitions of the # of heads when flipping four coins at once ?

Bingo Review 2.1 to 2.4 (Slide 5)9.

Bingo Review 2.1 to 2.4 (Slide 6)10) In a normal distribution curve mean, _____, and

mode are all represented by the same number.

11) Histograms are best for displaying what kind of numerical data?

Bingo Review 2.1 to 2.4 (Slide 7)12. A distribution of SAT Math scores for 130 students at asuburban high school provided the following statistics: Min.:485, Q1: 502, Median: 520, Q3: 544, Max.: 610, Mean: 535,Std. Dev.: 88. Which of the following is true?A. The distribution is skewed to the left and there are no

outliers.B. The distribution is skewed left and there is at lease one

outlier.C. The distribution is skewed to the right and there are

outliers.D.The distribution is skewed to the right and 65 students

scored better than 520.E. The distribution is skewed to the right and 65 students

scored better than 535.

Quiz directions• Read carefully.• Write out sentences if it says explain, compare,

describe.• When drawing the boxplot from the cumulative %

or cumulative frequency graph, I understand you are estimating.

• When you finish turn in your quiz and work on the h.w. 2.4 E#49 and #53