Descriptive Statistics




Exercise A

Descriptive Statistics

Using the test scores given in the table below, complete parts (a) through (c):

Table 1. Scores for Sixth Grade Students on Tests of Reading, Spelling, and Mathematics (N=52)

Name                          Gender      Class*      Reading (45)**   Spelling (80)      Math (65)

aaron andrews             1                1               32                        64                       43

byron biggs                 1                1               40                        64                       37

charles cowen             1                1               36                        60                       38

donna davis                 2                1               41                        74                       40

erin edwards               2                1               36                        69                       28

fernando franco          1                1               41                        67                       42

gail galaraga               2                1               40                        71                       37

harpo henry                 1                1               30                        51                       34

irrida ignacio              2                1               37                        68                       35

jack johanson              1                1               26                        56                       26

kleven klipsch            1                1               28                        51                       25

laverne lappenski       2                1               36                        57                       53

mary madison             2                1               39                        68                       37

nathan natts                1                1               22                        47                       22

oprah oates                 2                1               36                        59                       33

petula peters               2                1               32                        64                       33

quadra quickly            2                1               21                        44                       19

rahim roberts              1                1               29                        64                       43

slaim salik                  1                1               41                        76                       33

thomas tank                1                1               35                        65                       38

usaka urban                 2                1               41                        65                       38

victor vasquez            1                1               37                        68                       40

wakana watanabe        2                1               25                        53                       21

xenum xerxes             1                1               25                        54                       31

yuan young                 1                1               32                        59                       24

zebulon zibberts         1                1               42                        73                       44

angela ash                   2                2               43                        64                       52

belinda brown             2                2               33                        38                       41

charlotte cowen          2                2               33                        47                       50

dominik dubrow         1                2               39                        66                       34

erik eriksen                 1                2               39                        55                       47

francis french             2                2               38                        59                       49

guido garcia                1                2               31                        52                       29

hillary huan                2                2               38                        61                       48

igo ivanovich              1                2               33                        53                       43

jill johanson                2                2               42                        61                       45

kaleen knowles           2                2               35                        55                       51

larry lewis                   1                2               29                        40                       34

moe mastrioni            1                2               36                        58                       39

nancy nowits               2                2               28                        44                       44

orden orford                1                2               35                        53                       38

petre popovich            1                2               36                        52                       53

quincy quirn               1                2               33                        48                       33

rhonda rostropovich   2                2               31                        50                       31

sally stebbens             2                2               33                        51                       32

thelma thwaites          2                2               38                        43                       45

uriah urdahl                1                2               42                        61                       60

velma vauter               2                2               29                        49                       36

william westerbeke    1                2               33                        54                       33

xena xerxes                 2                2               30                        57                       37

yannita younts            2                2               44                        63                       49

zephina zoro               2                2               30                        47                       38

*Ms. Johnson’s class = 1; Mr. Cordero’s class = 2

**Maximum score in parentheses.

(a) create a grouped frequency distribution of all spelling test scores, including both classes (N=52)—be sure to include intervals (using the “Rule of 15”), counts, cumulative frequencies, and cumulative percentages;

(b) calculate the mean (rounded to nearest whole number), median, and mode of spelling test scores for each Ms. Johnson’s and Mr. Cordero’s classes;

(c) calculate the variance (s2) and standard deviation (s) of spelling test scores for each class; be sure to show your calculations (or if Excel or SPSS was used, document your steps):