Quiz 3 Results (Review for Midterm 1)

Results

Problem 1 Everyone scored 100% (4/4) (1)Are the following variables categorical (c) or quantitative (q)? a.__q__ Age (in years) b.__c__ Age (possible choices are “old”, “young”, “average”) c.__q__ Number of credit hours d.__c__ Gender

Problem 2 Each part was worth 1 for a total of 4 (2) Consider the following cross-tab table. It is a sample taken from a room full of professionals at Aultman Hospital last year: Profession Statistician Doctor Lawyer Tall Short __105__ How big was the sample size? __44.4__ Percent of statisticians that are tall? __57.1__ Percent of people that are doctors or lawyers? __Lawyers__ Who is more likely to be tall – Statisticians or lawyers? Percent of Lawyers that are tall = 10/15 Percent of Statisticians that are tall = 20/45

Problem 3 Each part was worth 1 for a total of 3 (3) Indicate whether the following are measures of variation/spread/center. __c__ Median __s__ Range __v__ Standard Deviation

Problem 4 Was worth 1 point (4) Which of the following is the least effective way to graph a categorical variable? (Choose one) ____ Pie Chart _x___ Histogram ____ Bar Chart

Problem 5 Each part was worth 1 point for a total of 5 (5) Consider the following Histogram (actual histogram of class grades so far in the semester). THERE WERE 31 OBSERVATIONS: __5/31__ Percent of students with a failing grade (65% is the D/F cutoff point) __5+6__ Number of students with an A (90% is the A/B cutoff point) __( )/31__ Percent of students with an A or an F __Left__ Is this histogram skewed to the right (R), left (L), or symmetric (S)? __No__ Based on your answer in part D, is the mean larger than the median? Left: mean < median Right: mean > median Sym: mean = median

Problem 6 Each part of 5 number summary is worth 1, standard deviation calculation is worth 3; Total of 8 possible points. (6) Give me the five number summary and calculate the standard deviation of: 35, 25, 30, 15, 10, 25, 35 10, 15, 25, 25, 30, 35, 35 10, 15, 25, 25 25, 30, 35, 35 Min: 10 Q1: (15+25)/2=20 Q3: (30+35)/2=32.5 Q2: 25 Max: 35 yy-mean(y-mean) (-15) (-10) s 2 =( )/(7-1)=91.7 S=sqrt(91.7)=9.6

Problem 7 Each part was worth 1 point (total of 5) (7) __2__ How many outliers are in the following box plot? _1,12___ What is the largest and the smallest value in the data? __6__ What is the median in the data? _yes___ Is Q1 the smallest non-outlier data point? _9___ What is the second largest value in the data set?

Problem 8 Each part was worth 1 point (total of 2) (8) Consider the left scatter plot (Left) and the right scatter plot (Right). ___positive_ What is the direction of the first scatter plot? ___.56_ One graph has a correlation of r=.85 and the other has r=.56. What is the correlation of the second graph?

Problem 9 Each part was worth 1 point (total of 3) (9) ____Stem & Leaf___________ What is the name of the graph below? _______22________ What is the mode of the graph below? _______Right________ If possible, determine the skewness of the following data