Chapter 3: Numerically Summarizing Data

Question 1

arithmetic mean

Answer 1

addition of all values in the data set and dividing by the number of observations

Question 2

population arithmetic mean (µ)

Answer 2

mean of all individuals in population

Question 3

sample arithmetic mean (x̄)

Answer 3

mean of all individuals in sample

Question 4

median (M)

Answer 4

number in middle of data in ascending order

Question 5

mode

Answer 5

value occurring most frequently in data set

Question 6

distribution

Answer 6

relative frequency histogram that has been “smoothed over;” (class width decreased, sample size n increased)

Question 7

unimodal distribution

Answer 7

one mode; “normal/bell curve”

Question 8

bimodal distribution

Answer 8

two modes

Question 9

multimodal distribution

Answer 9

more than two modes

Question 10

skewed right

Answer 10

tail to right; “positively skewed”

Question 11

skewed left

Answer 11

tail to left; “negatively skewed”

Question 12

z-score

Answer 12

distance a data value is from the mean in terms of standard deviation

Question 13

percentiles

Answer 13

number k such that k% of observations are less thatn or equal to the value

Question 14

quartile

Answer 14

percentile that divides the data into quarters

Question 15

interquartile range (IQR)

Answer 15

Q3-Q1

Question 16

outliers

Answer 16

extreme observations outside the fences

Question 17

fences

Answer 17

cut off point to determine the outliers
LF= Q1-1.5IQR
RF=Q3+1.5IQR

Question 18

box-whisker plot

Answer 18

grpah showing the five number summary of data