Statistics 3470
Introduction to Probability and Statistics I
Instructor:
Dr. Juhee Lee
When:
MWF 10:2011:15am
Email:
[email protected]
Where:
EA0160
Office:
205B Cockins Hall
Office Hours:
WF 3:004:00pm
(or by appointment)
Course information available at
STAT 3470 Homework 1
Due: January 16th (submit in class OR put in the stat 3470 drop box outside 413
Cockins Hall by 5:00PM
To receive credit please follow the instructions given in the syllabus. All numbered problems are
from the course textbook.
Aim of
STAT 3470 Homework 2
Due: January 29th (submit in class OR put in the stat 3470 drop box outside 413
Cockins Hall by 5:00PM
To receive credit please follow the instructions given in the syllabus. All numbered problems are
from the course textbook.
Aim of
STAT 3470 Homework 3
Due: February 6th (Wednesday) (submit in class OR put in the stat 3470 drop box
outside 413 Cockins Hall by 5:00PM
To receive credit please follow the instructions given in the syllabus. All numbered problems are
from the course textb
STAT 3470 Homework 4
Due: February 18th (Monday) (submit in class OR put in the stat 3470 drop box
outside 413 Cockins Hall by 5:00PM
To receive credit please follow the instructions given in the syllabus. All numbered problems are
from the course textboo
Stat 4288 (Spring 2013)
Introduction to Probability and Statistics for Engineers
Lecturer
Name: Dr. Juhee Lee
Email: [email protected]
Oce hours: Wednesday and Friday 3:004:00pm or by appointment
Oce: Cockins 205B
Grader
Name: Juemei Hu
Email: [email protected]
STEP BY STEP: Find the mean, mode, and median of the data
1.Compute the mean of the data: key in =AVERAGE(A2:A16) in a blank cell.
2. Compute the mode of the data: key in =MODE(A2:A16) in a blank cell.
3. Compute the median of the data: key in =MEDIAN(A2:
Part 1 of 1 
Question 1 of 10
60.0/ 100.0 Points
0.0/ 10.0 Points
For an exchange to occur that is recorded as a transaction in the accounting records, both sides of
the accounting equation must be affected.
A. True
B. False
Answer Key: False
Question 2
Week 2 Quiz Review
Question 1 of 10
10.0/ 10.0 Points
The primary function of the general ledger is to store transactions by account classification and to
provide a balance of each account.
Correct
A. True
B. False
Answer Key: True
Question 2 of 10
10.0/
Question 1 of 20
1.0/ 1.0 Points
Results from previous studies showed 79% of all high school seniors from a certain city plan to attend
college after graduation. A random sample of 200 high school seniors from this city reveals that 162
plan to attend col
art 1 of 9 
Question 1 of 25
1.0/ 1.0 Points
1.0/ 1.0 Points
The amount of time needed to run the Boston marathon is an example of which type of variable?
A.qualitative
B.discrete
C.none of the above
D.continuous
Answer Key: D
Part 2 of 9 
Question 2 of
Part 1 of 16 
1.0/ 2.0 Points
Question 1 of 23
1.0/ 1.0 Points
The chisquare goodnessoffit test can be used to test for:
A.difference between population means
B.difference between population variances
C.significance of sample statistics
D.normality
An
What is Probability?
What do we mean when we say the probability of an event is something?
Frequentist Interpretation of Probability
The probability of an event E is the long term proportion of the time
that the experimental outcome is E, when the experim
Counting Techniques
Focus on the situation where S is finite and has N outcomes, and all N
simple events are equally likely.
Let A be an event, and N(A) be the number of outcomes in A:
Section 2.3
1
Sometimes you can enumerate and then count by hand.
Exam
Conditional Probability
In many experiments, knowing one event has occurred can
modify our assignment of probability to other events.
Motivating Example: Disease Status and Testing
In a given population of people, 43 people have a particular disease (D
+)
Random Variables (RV)
In most applications we are usually interested in one or more real
valued measures of the outcome of the experiment:
1) lifetime of an electronic part
2) lifetime of a prosthetic device
3) # of defects in a semiconductor wafer
4) yie
Probability Distributions: Review
(Probability) Distribution of X means the specification of:
pmf of X
or
cdf of X
Today: Some numerical summary measures of distribution of X
1. Expected value of X
2. Variance of X
Section 3.3
Expected Value of Discrete R
Probability Models for Random Variables
Section 3.4
Most of our discussion of probability so far has been related to
an experiment with a finite sample space
where each outcome of the experiment is
equally likely
which lets us compute probabilities of eve
The Poisson Distribution
Section 3.6
Developed in 1830 by SimonDenis Poisson to describe the number
of times a gambler would win a rarelywon game of chance in a large
number of tries.
X = # of wins, n = # of tries, p = prob. of winning a game (small!)
E
Continuous Random Variables
Sections 4.1, 4.2
Recall: X is a continuous random variable if its set of possible values is
an interval (finite or infinite interval).
Reality.
A continuous random variable is used as a model for a quantity that,
in principle,
The Uniform Distribution
Section 4.2 cont.
Def: A continuous RV X is said to have a uniform distribution on
the interval [A , B] if the pdf of X is
Notation
The Uniform Distribution
Example: Say that the # of minutes past 8:57 that a student arrives at
th
The Normal (Gaussian) Distribution
Section 4.3
1. Most important continuous probability model / distribution in statistics
2. Is used for many physical measurements
heights, weights, test scores (also for errors in measurement)
3. Central Limit Theorem

Beyond the Normal Distribution
Section 4.4
Normal Distribution  N(, 2)
Continuous distribution, defined on entire real line
Symmetric
What if we want to model a RV that should have a skewed distribution?
Income
Time until the next hit on a web page
Question 1 of 20
1.0/ 1.0 Points
The staff at a small company includes: 4 secretaries, 20 technicians, 4 engineers, 2 executives, and 50
factory workers. If a person is selected at random, what is the probability that he or she is a factory
worker?
A.1/4