Exam 2

MATH106 - Statistics 1 Module 2 Exam Page 1 Grade: For each of the following, shade the correct answer in a new color. 1) 1 0 2) 1 0 3) 1 0 4) In a data set, the mode will always be unique. 4) 1 0 5) One disadvantage of the median is that it is not unique. 5) 1 0 6) 1 0 7) 1 0 8) 1 0 9) 1 0 10) 1 0 Provide the best answer for the following questions. 11) 0 12) Mode 1) When the mean is computed for individual data, all values of the data set are used. 2) A single, extremely large value can affect the median more than the mean. 3) One-half of all the data items will fall above the mode, and one-half will fall below the mode. 6) If a person's score on an exam corresponds to the 75th percentile, then that person obtained 75 correct answers out of 100 questions. 7) A negative relationship between two variables means that for the most part, as the x variable increases, the y variable decreases. 8) A correlation coefficient of -1 implies a perfect linear relationship between the variables. 9) When the correlation coefficient is significant, you assume that x causes y. 10) The strength of the relationship between two variables is expressed by the value of r. 11) What is the value of the mode when all values in the data set are different? 12) When data are categorized as, for example, places of residence (rural, suburban, urban) which measure (mean, median, mode or midrange) is the most appropriate measure of central tendency?

MATH106 - Statistics 1 Module 2 Exam Page 2 13) Mean 14) Standard Deviation 15) Midrange 16) Left 17) Two modes 18) Outlier 19) Independant 20) -1.00 1.00 21) The sign of r and the _________ will always be the same. 21) Slope 22) Line of best fit 23) -0.70 0.70 24) Interpolation 25) y=a+bx 13) Of the following list, which is NOT part of the five-number summary? {Q1, Q3, Mean, Median, Minimum , Maximum} 14) The positve square root of the variance is called the ______. (This is two words.) 15) When the sum of the lowest data value and the highest data value is divided by two, the measure is called the __________. 16) If the mode is less than the median which is less than the mean, then the distribution is _________ skewed. 17) If a graph is said to be bimodal, it means that it has _______. 18) An extremely high or extremely low data value is called an __________. 19) In a scatterplot, the x variable is called the ________ variable. 20) The value of r will always be between ______ and _______. (Two values) 22) The regression line is called the ____________. (I gave you several possible names, just pick one.) 23) Correlation is considered strong for a data set if the value of r is greater than ________ or less than _________. (2 values) 24) When using a line of best fit to predict an unknown value, which will give you a more predictable answer, interpolation or extrapolation? 25) What is the general equation used in statistics for the regression line? (This is a formula, not a name.)

MATH106 - Statistics 1 Module 2 Exam Page 4 Dennis 2 3.6 Scott 10 2.77 Michael 8 2.45 Use Excel to create a scatterplot and help you answer the questions below? a) What is the equation for the line of best fit? a) y= 3.7355 -0.0679x b) What is the correlation coefficient? b) 0.5993 c) Negative d) Is the correlation strong or weak? d) Weak e) 2.92 28a) Young 28b) 28b) How did you determine this ? Player Young 205 236.33 37.5 28c) Young's z-score = 198.70 Smith 209 240.08 44.38 28d) Smith's z-score = 203.59 17.5 17.3 23.7 37.6 19.3 25 19.1 41.7 16.9 22.9 18 24.3 16.5 19.7 20 17.2 25.2 24 17.2 18.2 36.8 47.7 25.1 21.4 16.9 20.4 23.2 16.8 24.1 25.4 31.7 38.5 17.4 28.6 25.2 20.1 25.9 26.8 35.2 35.4 31.7 17 18 21.6 19.8 29.1 24 31.4 19.1 25.5 Use Excel to calculate the following: (Please put your Excel command in the shaded cell.) Mean = 24.4220 Median = 23.4500 Midrange= 39.4500 Mode = 18 c) Is the correlation is positive, negative or none? c) e) If another student games for 12 hours, what could we expect his GPA to be? 28) During one NFL season, Steve Young (San Francisco 49ers) and Emmit Smith (Dallas Cowboys) had the following weights. 28a) With respect to his team, who was lighter, Smith or Young? I determined this by looking at th showed that Young's z-scores we Smith's. Player weight Team Mean Team Std Dev 29) The data shown are the total compensation (in millions of dollars) for the 50 top-paid CEOs for a recent year. Consider this a sample for calculations. 0 5 10 15 20 25 30 0 0.5 Gaming Hours

MATH106 - Statistics 1 Module 2 Exam Page 5 31.7 Variance= 54.5609 Standard Deviation = 7.3865 16.9 25.2 17.2 19.1 24 9 4 0 7 8 2 11 0 2 37 12 6 4 3 8 7 3 4 Minimum value = 0 Maximum value = 37 Q1 = 3.0000 Q2 (Median) = 5.0000 Q3 = 8.0000 Mean = 7.0556 Midrange= 18.5000 Mode = 4 Variance= 67.9379 Standard Deviation = 8.2424 24 23 25 23 30 29 28 26 33 29 24 37 25 23 22 27 28 25 31 29 25 22 31 29 22 28 27 26 23 21 25 21 25 24 22 26 25 32 26 29 Use Excel to calculate the following: (Please put your Excel command in the shaded cell.) 21 37 Mean = 26.2500 Median = 25.5000 Midrange= 29.0000 Mode = 25.0000 Variance= 12.7564 Standard Deviation = 3.5716 30) A sample of eighteen students are randomly selected and asked how many books they have read in the past year. The results are as follows: Use Excel to calculate the following for the sample then create a boxplot for the data: (Please put your Excel command in the shaded cell.) 31) The 11th Edition of The Pro Football Encyclopedia gave the following information. This is a random sample of pro football player ages in years. This c Editin will pe

MATH106 - Statistics 1 Module 2 Exam Page 7 he z-scores which ere lower than

MATH106 - Statistics 1 Module 2 Exam Page 8 Put your boxplot here. chart isn't available in your version of Excel. ng this shape or saving this workbook into a different file format ermanently break the chart.