Statistics 251: Introduction to Mathematical Probability (Section 2)

Lecture: MWF 11:30am-12:20pm, on Zoom
Textbook: A First Course in Probability by Sheldon Ross (6th, 7th, 8th, or 9th edition)
Course Information: syllabus and schedule
Instructor: Yi Sun (, office hours 12:20pm-1:30pm Monday on Zoom.

Overview and prerequisites

This course covers fundamentals and axioms; combinatorial probability; conditional probability and independence; binomial, Poisson, and normal distributions; the law of large numbers and the central limit theorem; and random variables and generating functions.

One of the following courses is a prequisite for this course:

Contact me by email if you have questions about whether this course is appropriate for you.

Course Policies

Gradescope: This course will use Gradescope, an online platform for grading exams and homework. Students registered for the course on the first day of class should have received an email to sign up for Gradescope. If you are enrolled in the course and do not have an account, email me immediately. A few notes about Gradescope:

Homework: There will be weekly written homeworks due Monday. Homeworks are posted here. Homework should be submitted electronically via Gradescope before the start of class. To submit on Gradescope, see this Youtube video or follow the steps below:

  1. Produce a legible .pdf file containing your complete solutions to each problem. This does not mean you must type up your solutions; instead, you may scan your handwritten solutions. Some guidelines for scanning are:
    • Gradescope recommends several free mobile/tablet apps which allow you to turn photos into multi-page PDFs. I also suggest using Dropbox mobile scanning.
    • Be sure to preview your scan and make sure it is legible before uploading to Gradescope.
  2. Upload the .pdf file to Gradescope by the submission deadline (11:30am Monday).
  3. Select the page(s) that contain the solution to each of the assigned problems. Failure to do this step will mean that some or all of your problems will not be graded!
Email me or the TAs if you have trouble with the submission procedure.

Exams: There will be one midterm exam and a cumulative final exam according to the following schedule.

The use of notes, textbooks, or electronic devices will not be allowed during exams. No make-up exams will be offered without a letter from the dean or a doctor’s note. No make-ups are possible for the final exam.

Grading: The final course grade will be determined according to the maximum of the two following computations:

The lowest homework scores will be dropped to accommodate illness and other unforeseen circumstances. Late homework will not be accepted.

Collaboration and Academic Integrity: I encourage you to work together on homework! For written homework, you must write your solutions alone and understand what you write. When submitting your homework, you should cite any sources you used (in print, online, or human) other than the textbook and myself.

Students with disabilities: In order to receive disability-related academic accommodations, students must first be registered with Student Disability Services (SDS). More information on the SDS registration process is available here. Registered students must present an accommodation letter to the instructor before exam or other accommodations can be provided. Students who have, or think they may have, a disability are invited to contact SDS for a confidential discussion.



Getting Help

Peer Tutoring: UChicago offers peer tutoring via the Core Tutoring Program. See more information here.

Contact me: Please come to office hours or email me or one of the TAs for help if you are having difficulty with the material.