# COMPSCI 240 (Reasoning Under Uncertainty) - 2022 Fall

## Instructors

Jie Xiong,     Office: A341 LGRC;            Email: jxiong@cs.umass.edu;        Phone: 413-577-0368

## Teaching Assistants

Zack While, Alexandra Burushkina, Ankur Aditya, Mengxue Zhang, Yuda Feng, Zhangqi Duan, Ignacio Gavier

## Lectures

MoWe 2:30PM - 3:45PM in Marcus 131

## Course Objectives

Students in this 4-credit course will learn the basic concepts of counting and probability while developing mathematical reasoning skills for problems that involve uncertainty. Each concept will be illustrated by real-world examples and demonstrated through in-class and homework exercises. Topics in counting and probability include: basic counting problems, probability definitions, mean, variance, binomial distribution, discrete random variables, continuous random variables, Markov and Chebyshev bounds, laws of large numbers, and central limit theorem. Probabilistic reasoning skills will center around conditional probability and odds, Bayes' law, Markov chains, Bayesian networks, and Markov decision processes.

## Prerequisites

COMPSCI 187 and MATH 132 with a grade of 'C' or better.

1. Moodle: Moodle is going to be the primary communication platform for this class.

2. Textbook: Introduction to Probability, 2nd Edition by Dimitri P. Bertsekas and John N. Tsitsiklis.

3. Exam 1:   Time and Date: 2:30-3:30pm on 10/17 (Monday);   Location: Marcus 131
4. Exam 2:   Time and Date: 2:30-3:30pm on 11/14 (Monday);   Location: Marcus 131
5. Final Exam:   Time and Date: 3:30-5:30pm on 12/20 (Tuesday);   Location: Marcus 131

1. Weekly Quiz in Moodle (10 of them) 10%

2. Homeworks (4 of them) 20% [We will drop your lowest homework score when computing your final grade]

3. Midterm 1 20%

4. Midterm 2 20%

5. Final 30%

Any regrade requests for homework or exams must be submitted within one week after work is returned to you. Please discuss regrading issues only during office hours.

## Schedule

• Wed 9/07: Logistic of the course, introduction, set theory

• Mon 9/12: Probability axioms, Conditional Probability

• Wed 9/14: Sequential Models, Bayes' Rule

• Wed 9/14: Quiz 1 release

• Mon 9/19: Bayes' Rule, Independence, Conditional Independence

• Mon 9/19: Homework 1 release

• Wed 9/21: Counting, Binomial Law

• Wed 9/21: Quiz 2 release

• Mon 9/26: Counting, Discrete Random Variables

• Wed 9/28: Discrete Random Variables

• Wed 9/28: Quiz 3 release

• Mon 10/03: Expectation

• Mon 10/03: Homework 2 release

• Wed 10/05: Variance / Functions of R.V.

• Wed 10/05: Quiz 4 release

• Mon 10/10: Holiday, no class

• Wed 10/12: Multiple Random variables

• Mon 10/17: Exam 1

• Mon 10/17: Quiz 5 release

• Wed 10/19: Continuous Random Variables

• Mon 10/24: Common Continuous Random Variables

• Wed 10/26: Joint PDF, CDF Markov and Chebyshev Inequalities

• Wed 10/26: Quiz 6 release

• Mon 10/31: Central Limit Theorem and Laws of Large Numbers

• Mon 10/31: Homework 3 release

• Wed 11/02: Covariance and Correlation

• Wed 11/02: Quiz 7 release

• Mon 11/07: Game Theory 1

• Wed 11/09: No class

• Mon 11/14: Exam 2

• Wed 11/16: Game Theory 2

• Wed 11/16: Quiz 8 release

• Mon 11/21: Markov Chains 1

• Wed 11/23: Holiday, no class

• Mon 11/28: Markov Chains 2

• Wed 11/30: Bayesian Network

• Wed 11/30: Quiz 9 release

• Wed 11/30: Homework 4 release

• Wed 12/07: Review for Final Exam

• Wed 12/07: Quiz 10 release

• Tue 12/20: Final Exam

## Turning in Assignments

Turning homework in late helps no one. When students turn homework in late, they fall behind, and then cannot receive feedback on time. TAs and UCAs then cannot grade things in a timely way, because they have started to move into the next topic. Instructors cannot detect what material needs to be re-emphasized, etc. Because of this, the general rule is that late homework will not be accepted. The only exception to this are justified medical or personal situations that fall outside the ordinary. Since we don't want to be the arbiter of what is a good justification and what isn't, if you have a medical or personal reason for turning homework in late you must get appropriate documentation from the Dean of Students Office. If they don't think that you are justified, neither do we. To provide some flexibility, we will drop your lowest homework when computing your final grade, but be careful how you use this option; deliberately blowing off an assignment is not a good idea.

Once returned, students have until the next Friday discussion session to let the instructor/TAs know about any grading dispute/concern; do this via Gradescope. No change in grades will be recorded after one week of returning the homeworks. NO exceptions.

## Attendance Policy and Missing an Exam

Please try to attend every class and every discussion session; it is very hard to do well in the course if you miss too many of these. With a doctor’s note and/or legal documents that comply with the University’s Class Absence Policy, you will be able to take a make-up exam.

## Online Discussion Forum

We will use Piazza for class discussions and for all course announcements. You can sign up here. Rules for using Piazza are as follows:

• You must converse respectfully with each other and with the teaching staff.
• Posts are restricted to topics directly related to the class.
• You may post anonymously (to other students), but do not abuse this privilege
• You are encouraged to help other students via posting (subject to the above restrictions).
• For private matters you can post privately or email the teaching staff.
Please do not email the instructors or the TAs with math questions. Use discussion sessions, office hours, and Piazza.

## Covid Policy

For the health and safety of all members of our campus community, students are expected to follow all COVID-related policies on campus.

(Added Aug. 17, 2022) UMass is a mask welcome campus, and we encourage everyone to respect the choices that individuals make about their own masking. Masking is strongly encouraged during the first few weeks of the fall semester, particularly in crowded settings, or for individuals who are at increased risk of severe illness from COVID-19.

(Updated July 28, 2022) Regardless of your vaccination status, if you test positive you must isolate for a minimum of five days and wear a mask on days 6-10. If you test positive using UMass testing facilities, a UMass public health case manager will call and give you specific instructions. If you test positive through a different facility, isolate in place and report your results to the Public Health Promotion Center immediately by emailing testing@umass.edu.

## Equity and Inclusion Statement

We are committed to fostering a culture of diversity and inclusion, where everyone is treated with dignity and respect. This course is for everyone. This course is for you, regardless of your age, background, citizenship, disability, education, ethnicity, family status, gender identity, geographical origin, language, military experience, political views, race, religion, sexual orientation, socioeconomic status, or work experience. We bring different skills to the course and we will all be learning from and with each other.

In both live and online settings we all are expected to uphold and promote a welcoming environment for learning. Politeness, kindness, and tolerance are expected at all times. Respect that people have differences of opinion, and work and approach problems differently. Please keep unstructured critique to a minimum and make sure that any criticism is constructive. Try and be aware of your own biases and avoid micro-aggressions. Listen to others and let them participate; ask yourself whether you dominating a conversation and not giving others a chance to contribute. Disruptive behavior is not welcome, and insulting, demeaning, or harassing anyone is unacceptable. We follow the university's guidelines for classroom civility. In particular, we don’t tolerate behavior that excludes people in socially marginalized groups. If you feel you have been or are being harassed or made uncomfortable by someone in this class, please contact a member of the course staff immediately, or if you feel uncomfortable doing so, contact the Dean of Students office.

The Association of Computing Machinery (ACM), the world's largest professional computing society, has released a Code of Ethics, and with good reason. Given the dominant role of computer technology in our society, ethical lapses can have disastrous consequences. Ethical behavior begins here at UMass. The following discussion pertains to academic honesty from the perspective of this course.

All work submitted must be your own in presentation. How much outside help is allowed depends on the course component.

• For quizzes and exams, no outside help or use of materials from prior years is allowed. Any cheating on a quiz or exam is grounds for an F in the course.
• You may discuss homework with other students, in fact we encourage this as a learning experience. But again, the writeup must be your work. Copying is not allowed, and collaboration so close that it looks like copying is not allowed. In general, if we receive two identical homeworks we will accept neither of them (i.e., both get F's) and will give you a stern warning that could lead to formal action the next time. A good practice is to divide your work into an "ideas phase" where you collaborate and a "writeup phase" where you work alone -- enter the writeup phase with notes, but not written solutions.
• If you make use of a printed or on-line source for the homework, other than specific course materials such as the textbook or website, please mention it in your writeup. Of course copying a solution to a problem from the web is cheating, and this is easier for us to detect than you might think.
• As per CICS policy, no student shall post course materials online without explicit permission of the instructor. Nor shall a student provide course materials to a third party such as StudySoup.

For more information about what constitutes academic dishonesty, please see the Dean of Students' website for the general UMass academic honesty policy. Since students are expected to be familiar with this policy and the commonly accepted standards of academic integrity, ignorance of such standards is not normally sufficient evidence of lack of intent. You can take a quick online quiz online quiz to check your "academic integrity quotient (AIQ)".

Our lectures and course materials, including slides, videos, assignments, tests, outlines and similar materials, and all course recordings, are protected by U.S. copyright laws and by university policy. We are the exclusive owner of the copyright in materials we create. You may take notes and make copies of course materials for your own use in this class. You may also share those materials with another student who is registered and enrolled in this course. You may NOT reproduce, distribute, upload, or display any lecture notes or recordings or course materials in any other way — whether or not a fee is charged — without the instructors' express written consent. If you do so, you may be subject to disciplinary action under the UMass Code of Student Conduct. Similarly, you own the copyright to your original papers and exam essays. If we are interested in posting your answers or papers on the course web site, we will ask for your written permission.

## Disability Statement

The University of Massachusetts Amherst is committed to making reasonable, effective and appropriate accommodations to meet the needs of students with disabilities and help create a barrier-free campus. If you are in need of accommodation for a documented disability, register with Disability Services to have an accommodation letter sent to the instructors. It is your responsibility to initiate these services and to communicate with the teaching staff ahead of time to manage accommodations in a timely manner. For more information, consult the Disability Services website.

## Title IX Statement

UMass is committed to fostering a safe learning environment by responding promptly and effectively to complaints of all kinds of sexual misconduct. If you have been the victim of sexual violence, gender discrimination, or sexual harassment, the university can provide you with a variety of support resources and accommodations. If you experience or witness sexual misconduct and wish to report the incident, please contact the UMass Amherst Equal Opportunity (EO) Office (413-545-3464 | equalopportunity@admin.umass.edu) to request an intake meeting with EO staff. Members of the CICS community can also contact Erika Lynn Dawson Head, director of diversity and inclusive community development (erikahead@cics.umass.edu | 860-770-4770).