Statistics 10 Midterm_1682828889573

/ Stats 10 Lee 2 and 3: Midtern1 Version 1 Introduction to S tat istical Reasoning Mi chael Tsiang UCLA, Winter 201 8 Instructions: You have 40 minut es to complete the following questio ns . This exam is clo sed book. Yo 11 may use only one sh ee t of paper with handwritten not es . Non-graphing calculators are allowed. bnt no other electronic devices are allowed. Good luck! Academic Misconduct: Any pot ential violation of UCLA's poli cy on acade mi c integrity will be reported to the Office of th e Dean of Stud ents. All work on this exam must be yo ur own. In the Special Codes section of your scantron, fill in a 1 in the K column. UI ~ . '( , .,.,., e 12p.,.., CK) (Turn over when exam starts) l

.,t;:; ") 2 Stat s 10 L ee 2 and :~- ;-. \· - -- ---- ------------- --- - ------ --- -· ...... :.· 1, 11 , - ---:.:! Mark your answers to all multiple choi ce questions on the scantron provided . Any answ ers marked on these pages will not be scored . Probl em 1 The ti111 c yo u wa it in line to order a coo ki e at Diddy Riese would best be modeled as what type of \·a ri abl c? (a) N um e ri cal va ri able (b) Catego ri c al variable Problem 2 Coo ki e flav ors (chocolate chip, sugar cinnamon, oatmeal raisin walnut) at Diddy Riese would best be modeled as what type of variabl e? (a) Numerical variable (b) Cat egorical variable Problem 3 Th e number of waffl es Les li e Knope orders from JJ 's Diner would best be modeled as what type of variable? (a) Numerical variable (b) · Categorical variable Problem 4 Th e distribution of blood types for a sample of patients wou ld best be visualized by which plot? (a) Boxplot (b) Histogram (c) Bar chart (d) Scatterplot (e) None of the above Problem 5 Th e relationship between the number of waffles Leslie Knope orders and th e volume of whipp ed cream she puts on them would best be visuali ze d by which plot? (a) Boxplot (b) Histogram (c) Bar cha rt (d) Scatterp lot (e) None of the above itR :!. - p:11

I Stats 10 Lee 2 and 3· i\I "d • 1 term 3 Problem 6 Gr eg p·k·t · I· . . . l· . . . H 1 1 15 P ay ed on In s !u gh sc h oo l s so ccc1 · [ r, 11n an d basket ba ll team ast yem · e scor ed l 8 goals throughout th e soccer season a nd made 28 baskets throughout the ba sk et ba ll season. Th e following summa ri ze the tota l number of goals and baskets by each of his t ea m members throughout the season. ,i,, "' r Soccer Goals Ba ske tba ll Baskets Mean 10 25 SD 4 5 \6 16 Bas ed on these statistics alone, is Greg a be tte r soccer player or basketball player? e)) Gr eg is be tte r at soccer. (b) Greg is better at bask et ball. (c) Greg is equally good at soccer and basketball. (d) Cannot be determined from the information given. Problem 7 Mark Brendanawicz, the city planner for Pawnee, Indiana , sa ys, " The typical commute to work for someone living in the city limits is less than the commute to work for someone living in the suburbs." What does this statement mean? (a) If you live in the city limits you will have a longer commute time. (b) The center of the distribution of commute times for a city-dweller is less than the ce nt er of the distribution for those living in the suburbs. (c) All city <lwellers spend less time commuting to work than those living in the suburbs . . (d) There is less variation in the commute time of those living in the s uburb s. Problem 8 Below is the standard deviation for finish times (measured in ho ur s) of a 10k race for a randomly selected group of self-identified women a nd men. Please assume that the pe op le in the group were classified into only two genders, female and m~le. Women: s = 0.17 Men: s = 0. 21 Choose the statement that best summarizes th e meaning of the standa rd de,·iation. ~ n a~erage, n:en's ~nish. times will be 0. 21 hours faster than th e overa ll avera ge fini sh tim e. ave1a.ge , ,,omens fim sh t nn es will be 0. 17 hours less th an mcu ·s fini sh t im es. (c) ~he distribution of men's finish times is less va ried than the di st ribution of wom en·s fiu i :,u tunes. v ' ie c is nu uti lrn l)f lll t' ll ·s tin ish (d) Th e di str ibution of women's finish tim es is !es" v c· 11 ·1 ·ecl tl1 c·' . 11 tl 1· t · 1- tim es .