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Math 3081 (Probability and Statistics), Summer-II 2022



Course Information
Instructor Class Times Office Hours
Evan Dummit
edummit at northeastern dot edu
(Sec 1) MTWR, 1:30pm-3:10pm, Hurtig 130
(Sec 2) MTWR, 9:50am-11:30am, Dodge 050
R 3:30pm-5:30pm
or by appointment
Online, via Zoom
There are two sections of Math 3081, corresponding to the two lecture times listed. The lectures will cover the same material at the same pace.
For detailed information about the course, please consult the 3081 Course Syllabus. (Note: any information given in class or on this webpage supersedes the written syllabus.)
Teaching Assistant Problem Session / Office Hours
Jiewei Feng
feng.ji at northeastern dot edu
F, 1pm-3pm
Online, via Zoom
Nathan Zelesko
zelesko.n at northeastern dot edu
F, 3pm-5pm
Online, via Zoom
Math 3081 uses a Piazza page for course discussion. Links to all of the live lectures, office hours, problem sessions, and lecture recordings are hosted there.
All homework assignments are available on the 3081 WeBWorK page. All problems have unlimited attempts and you may work on the assignments at any time up until the due date. Your username is your Northeastern username, and your password is your 7-digit Northeastern ID number without the two leading zeroes.


Handouts / Lecture Notes
The instructor will write lecture notes for the course in place of an official textbook as the semester progresses. The course will follow the presentation in Larsen and Marx's "An Introduction to Mathematical Statistics and its Applications" (5th edition), but it is not necessary to purchase the textbook for this course.

For those students who are using the textbook, here are the correspondences between the notes and textbook:
Notes ch1: Book §2.1-2.7 (Probability)
Notes ch2: Book §3.1-3.9 + §4.1-4.3 (Random Variables)
Notes ch3: Book §5.1-5.4 (Parameter Estimation)
Notes ch4: Book §6.1-6.4 + §7.1-7.5 (Hypothesis Testing)
Notes ch5: Book §9.1-9.5 + §10.1-10.4 (Topics in Hypothesis Testing)
Handout Topics
Chapter 1: Counting and Probability (25pp, v3.00, posted 6/21) 1.1 ~ Sets and Set Operations
1.2 ~ Counting Principles
1.3 ~ Probability and Probability Distributions
1.4 ~ Conditional Probability and Independence
Chapter 2: Random Variables (34pp, v3.00, posted 7/7) 2.1 ~ Discrete Random Variables
2.2 ~ Continuous Random Variables
2.3 ~ The Normal Distribution, Central Limit Theorem, and Modeling Applications
Chapter 3: Parameter and Interval Estimation (18pp, v3.00, posted 7/25) 3.1 ~ Parameter Estimation
3.2 ~ Interval Estimation
Chapter 4: Hypothesis Testing (21pp, v3.00, posted 8/2) 4.1 ~ Principles of Hypothesis Testing
4.2 ~ One-Sample and Two-Sample z Tests
4.3 ~ Errors and Misinterpretations of Hypothesis Testing
Chapter 5: Topics in Hypothesis Testing (31pp, v3.00, posted 8/9) 5.1 ~ The t Distribution and t Tests
5.2 ~ The χ2 Distribution and χ2 Tests


Exam Information
Exams will be distributed in person during the course lecture period. Midterm exams are 90 minutes, while the comprehensive final is 2 hours and the short final is 1 hour.
Exam Date, Time, Location Topics Review Material
Exam 1
(Form A), (sols)
(Form B), (sols)
Mon, Jul 25th
In lecture
WeBWorKs 1-3
Notes §1.1-1.4 + §2.1-2.2
Exam 1 Review Problems (answers)
Review session Sat Jul 23rd, 1pm-3pm
Exam 2
(Form A), (sols)
(Form B), (sols)
Mon, Aug 15th
In lecture
WeBWorKs 4-6
Notes §2.3 + 3.1-3.3 + 4.1-4.3
Exam 2 Review Problems (answers)
Review session Sat Aug 13th, 1pm-3pm
Final Tue, Aug 23rd
10:30am-12:30pm
Comp: Churchill 101
Short: Churchill 103
Comprehensive:
WeBWorKs 1-7
Notes §1.1-5.2
Short:
WeBWorK 7
Notes §5.1-5.2
Short-Final Review Problems (answers)
Review sessions Sat Aug 20th + Sun Aug 21st, 1pm-3pm
For exams, you are permitted one "cheat sheet", consisting of a double-sided 8.5in-by-11in piece of paper. Calculators are permitted, but cell phones, other electronic devices, books, and additional notes of any kind will NOT be permitted in exams.


Old Exams
These are exams from previous Math 3081 courses, and are provided to give you an additional source of practice problems. Please note: some courses may have been organized differently than this course, so some material may differ from exam to exam. Some topics from our course may be covered or emphasized differently, or skipped altogether, and some topics on these exams may not appear on the exams in this course.
Exam 1 Exam 2 Exam 3 Final Exam
2018 Summer 1 (with solutions)

2019 Summer 2, (solutions)
2018 Summer 1, (solutions)

2019 Summer 2, (solutions)
2018 Summer 1, (solutions)

2019 Summer 2, (solutions)
2017 Spring, (solutions)

2017 Spring, (solutions)

2017 Spring, (solutions)

2017 Summer 2 (with solutions)

2018 Spring, (solutions)

2018 Summer 1, (solutions)


Tips For Success In This Course
Attend Lecture Missing lecture is a bad idea! If for any reason you cannot make it to a class, you should watch the recording of the lecture. You are responsible for all material covered in lecture.
Read the Lecture Notes (or Textbook) The lecture notes and the textbook are comprehensive sources of material for the course. The notes are intended as review material, although many students like to read them as preparation before attending the lecture on the corresponding topics. Please note that the electronic notes are not identical to the material covered in class: this is by design, so as to provide you a slightly different perspective on the material.
Use WeBWorK Effectively WeBWorK assignments are intended to help you learn the course material at a basic level. Look over the problems well before the due date, and work on them in concert with the corresponding lectures. You may use technology (calculators, Wolfram Alpha, computer software) and other people to help you (so long as you are submitting your own work), but be mindful: if you do not understand how to do the WeBWorK problems, you will almost certainly struggle on the exams. Exam problems are generally similar in style and difficulty to WeBWorK problems, but often feel harder because of the limited time and the fact that you do not have multiple attempts on the exam!
Attend Office Hours Office hours are specifically reserved for you to receive individual, one-on-one help from the instructor or TAs. Office hours will be the most effective when you have already put in effort to learn the material on your own (including trying to solve the homework problems), and when you come in with a list of specific questions or topics you are struggling with.
Use Tutoring Services The university offers a wide variety of free tutoring services. Over the summer, the Tutoring Center is open for students taking various math courses, including Math 3081.


Course Schedule
The schedule is subject to change! All sections refer to the course lecture notes.
Week Schedule
Week of July 4
(class starts 7/5)
§1.1: Sets and Set Operations
§1.2: Counting Principles
§1.3: Probability and Probability Distributions
§1.4.1: Conditional Probability
WeBWorK 1 due Sunday 7/10 at 5am Eastern.
Week of July 11 §1.4.2: Independence
§1.4.3: Computing Probabilities, Bayes' Formula
§2.1.1: Discrete Random Variables
§2.1.2: Expected Value
§2.1.3: Variance and Standard Deviation
§2.1.4: Joint Distributions
WeBWorK 2 due Saturday 7/16 at 5am Eastern.
Week of July 18 §2.1.5: Independence
§2.1.6: Covariance and Correlation
§2.2: Continuous Random Variables
§2.3.1: The Normal Distribution
§2.3.2: The Central Limit Theorem
Review for Exam 1
WeBWorK 3 due Saturday 7/23 at 5am Eastern.
Week of July 25
EXAM 1 in class on Monday, July 25th
§2.3.3: The Poisson Distribution and Poisson Limit Theorem
§2.3.4: The Exponential Distribution and Memoryless Processes
§3.1.1: Maximum Likelihood Estimates
§3.1.2: Biased and Unbiased Estimators
WeBWorK 4 due Saturday 7/30 at 5am Eastern.
Week of August 1 §3.1.3: Efficiency of Estimators
§3.2.1: Confidence Intervals
§3.2.2: Normal Confidence Intervals
§4.1: Hypothesis Testing
§4.2.1: One-Sample z Tests
§4.2.2: Two-Sample z Tests
WeBWorK 5 due Saturday 8/6 at 5am Eastern.
Week of August 8 §4.2.3: z Tests for Unknown Proportion
§4.3.1: Type I and Type II Errors
§4.3.2: Misinterpretations and Misuses of Hypothesis Testing
§5.1.1: The t Distributions
§5.1.2: Confidence Intervals Using t Statistics
§5.1.3: One-Sample t Tests
WeBWorK 6 due Saturday 8/13 at 5am Eastern.
Review for Exam 2
Week of August 15 (class ends 8/18)
EXAM 2 in class on Monday, August 15th
§5.1.4: Two-Sample t Tests
§5.1.5: Robustness of t Tests
§5.2.1: The χ2 Distributions
§5.2.2: χ2 Confidence Intervals and Hypothesis Tests
§5.2.3: The χ2 Test for Independence
§5.2.4: The χ2 Test for Goodness of Fit
WeBWorK 7 due Saturday 8/20 at 5am Eastern.
Review for Final Exam
Week of August 22
FINAL EXAM Tuesday, August 23rd, 10:30am-12:30pm, Churchill 101 (Comprehensive) / 103 (Short)