2.123 Which hospital is safer?
a. 3% of patients died in Hospital A.
2% of patients died in Hospital B.
2.124 Patients in poor or good conditions
a. Death rate for poor patients in Hospital A is .038
Death rate for poor patient
HW 11 Solutions
1. (13.8) The least squares method fits a regression line through a scatter diagram
by minimizing the error sum of squares, hence the name least squares. The least
squares regression line is the li
Random (Chance) Variable- variable whose value is determined by the outcome of a random
Discrete Random Variable- a random variable that assumes countable values
o Ex: number of cars owned by a family, number of houses on a bla
Sources of Data
o Coming from inside a company or source
o Sources from outside the company or source
o Primary data- data obtained from the organization that originally collected them
o Secondary data- data obtained from
Statistics and Types of Statistics
What is Statistics?
o Statistics- the science of collecting, analyzing, presenting, and interpreting data,
as well as making decisions based on such analyses
Types of Statistics
o Descriptive Statistics- methods for orga
Experiment, Outcome, and Sample Space
Experiment- process that results in one and only one of many observations
Outcomes- observations of the experiment
Sample Space- collection of all outcomes for an experiment
Simple and Compound Events
Event- a collect
Raw Data- data recorded in the sequence in which they are collected and before they are
processed or ranked
o Ungrouped Data Set- contains information on each member of a sample or
Organizing and Graphing Quantitative Data
Measures of Central Tendency for Ungrouped Data
o Measure of Central Tendency- gives the center of a histogram or a frequency
Three different measures of central tendency: mean, median, mode
o Mean- most frequently used measure of cent
2.27 Explanatory and response variables
a. Weight= response, age= explanatory
b. Reasonable to simply explore
c. Rental= response, number of bedrooms= explanatory
d. How sweet it is= response, amount of sugar= explanatory
10.10 Public University tuition; 2000 versus 2008
Based off of the plot I do not see any outliers or unusual values. A linear relationship between
the tuition in 2000 and 2008 does seem reasonable. The relationship seems to be a bit strong
being that t
a. Since Albinism is recessive and a person must have aa to have it. Beths brother received an a
from each parent.
b. If a child inherits an allele from both parents the probability is 0.5, so Aa=0.5, aa= 0.
1.30.Women seeking graduate and professional degrees
We cannot use a pie chart to display the data presented because all categories or pieces of the pie
need to equal a whole. When all numbers are added the total percentages e
5.10 Total Sleep time of College Students
a. 1.15/sqrt(200) = 0.078842
c. P[x-bar < 6.9] = 0.064002
5.12 Songs on the iPod.
a. 280/sqrt(10) = 88.544 seconds
b. 280/15 = 18.66667= n = (18.7)^2 = 348.4444 (349) songs
8.19 p^ and the normal distribution
a. p^ less than or equal to 0.2667 and greater than or equal to 0.5333
b. n=100, p^ < or equal to .30, > than or equal to .50
8.22 Student credit cards
? Didnt understand!
8.26 Do you enjoy d
4.55 Spell-checking software
b. x is less than or equal to 1= 0.3+0.3+0.2+0.1= 0.9
c. x is less than or equal to 2, when all probabilities less than 2, including x=2 are added together.
Probability = 0.3+0.3+0.1= 0.7