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Course number
CIS 421/521 - Artificial Intelligence
CIS 121 (for undergraduates)
CIT 594 (for MCIT students)
A data structure and algorithms course, plus substantial programming experience (for everyone)
Chris Callison-Burch
Discussion Forum
Time and place
In Fall 2021, the course will be in-person and broadcast live via Zoom. You are not obligated to attend in person. Everyone is welcome to watch the videos from home.
All lecture materials will be recorded and uploaded for students wishing to participate remotely. We also have pre-recorded lectures available for review.
The first day of class is Tuesday, August 31, 2021.
The first day of office hours will be Tuesday, September 7, 2021.
The final day of class is Thursday, December 9, 2020.
There are several sections of the class:
  • The Monday/Wednesday section meets from 8:30am-10am Eastern (Zoom link)
  • The Tuesday/Thursday section meets from noon-1:30pm Eastern (Zoom link)
Office hours (1-on-1 on
Mondays 9:15am-11:15am Eastern (Coco Zhao)
Mondays 10am-noon Eastern (Aditya Singh)
Mondays noon-2pm Eastern (Kit Wiggin)
Mondays 5-6pm Eastern (Roque Soto Castaneda)
Mondays 5-7pm Eastern (Brian Wong)
Mondays 8pm-10pm Eastern (Hanbang Wang and Will Bergstein)
Tuesdays 1-3pm Eastern (Artemis Panagopoulou)
Tuesdays 7pm-9pm Eastern (John Wallison)
Tuesdays 9pm-11pm Eastern (Yash Upadhyay)
Wednesdays 10am-12pm Eastern (Xavier Lee)
Wednesdays noon-2pm Eastern (Anna Orosz)
Wednesdays 4pm-6pm Eastern (Ruochun Wang)
Wednesday 9:30pm-11:30pm Eastern (Sherry Shi)
Thursdays 9am-11am Eastern (Yue Yang)
Thursdays 1pm-3pm Eastern (Yuxuan Huang)
Thursdays 5pm-7pm Eastern (Viranchi Patel)
Fridays 9am-11am Eastern (Zhi Zheng)
Fridays noon-2pm Eastern (Lisa Zhao and David Wang and Dinesh Jagai)
Fridays 2pm-4pm Eastern (Amy Guo and Harry Wang)
Fridays 4pm-6pm Eastern (Ruochun Wang and Dinesh Jagai)
Fridays 8pm-10pm Eastern (Enri Kina)
Saturdays 8am-10am Eastern (Helen Jin)
Saturdays 8:30am-10:30am Eastern (Aditya Singh)
Saturdays 2pm-4pm Eastern (Roque Soto Castaneda)
Saturdays 4pm-6pm Eastern (Harsh Goel)
Saturdays 7pm-9pm Eastner (Xingyu Fu)
Sundays 3pm-5pm Eastern (Roque Soto Castaneda)
Sundays 6pm-8pm (Steven Wang)
Sundays 7pm-9pm (Songyu Eve Yan)
Group Office Hours (Recorded)
Fridays 2pm-3pm Eastern (Chris Callison-Burch)
Required: Artificial Intelligence: A Modern Approach (4th edition) by Russel and Norvig. Note that the 4th edition adds substantial new material over the 3rd edition, so you should buy the 4th edition. You can buy the textbook on Amazon or from the UPenn bookstore, where you can rent the digital version for $40.
Supplemental: Speech and Language Processing (3rd ed. draft) by Jurafsky and Martin. This textbook is currently free online while the textbook authors are revising it to write their 3rd edition. We will use it in the last third of the course.
Materials for Extra Credit Assignments
In addition to the normal homework assignments, we will have a series of optional extra credit assignments that use programmable toy R2D2s. These assignments can be done in groups. Each extra credit homework assignment if worth up to about 1% towards your final grade. The total amount of extra credit earned will be divided among each student in a group (so students in a large group get less extra credit than students in smaller groups to refelct the effort done).
You can borrow one of the R2D2 robots from us. It must be returned at the end of the semester in good working order, or you will have to pay $100 to replace it.
  • 70% Homework Assignments
  • 30% Exams and Quizzes
    • 10% for weekly quizzes (equally weighted)
    • 10% for midterm 1
    • 10% for midterm 2
  • Up to 3-5% in Optional Extra Credit
The course is not curved. Your overall score is computed as 0.3 * exam score + 0.7 * homework score. All homeworks are equally weighted. Here is how letter grades are assigned based on your overall score:
Score Grade
≥ 97 A+
93-97 A
90-93 A-
87-90 B+
83-87 B
80-83 B-
75-80 C+
70-75 C
65-70 C-
50-65 D
below 50 F
Differences between 421 and 521
There is roughly one homework assignment per week, aside from weeks with exams. Students enrolled in CIS 421 may skip one HW assignment, or they may discard their lowest scoring HW assignment. You do not get late days back on the homework that you discard. Students enrolled in CIS 521 must complete all HW assignments and cannot discard their lowest scoring assignment.
Collaboration Policy
Quizzes and exams must be completed on your own without help from others. For quizzes or exams that are open notes or allow a “cheatsheet”, you must create the notes yourself and not use anyone else’s notes. Since exams are sometimes administered on different days, you should not discuss the exam with anyone else in the course until after the scores have been released.
Unless otherwise noted, you are not allowed to work in groups on the homework assignments. You can discuss homework problems with others (you must explicitly list who you discussed problems with on each homework submission), but 

all code must be your own independent work. You are not allowed to upload your code to publicly accessible places (like public github repositories), and you are not allowed to access anyone else’s code. If you discover someone else’s code online, please report it to the course staff via a private note on Piazza.
Late Day Policy
Each student has 5 free “late days”. Homeworks can be submitted at most two days late. If you are out of late days, then you will not be able to get credit for subsequent late assignments. One “day” is defined as anytime between 1 second and 24 hours after the homework deadline. The intent of the late day policy it to allow you to take extra time due to unforseen circumstances like illnesses or family emergencies, and for forseeable interruptions like on campus interviewing and religious holidays. You do not need to ask permission to use your late days. No additional late days are granted.