CS109: Probability for Computer Scientists
Fall 2022
Monday, Wednesday, Friday 3:00pm - 4:20pm in-person in NVIDIA Auditorium

Week 9 TODO

Finish your Challenge
Start PSet 6

Teaching Team

Professor: Chris Piech

Awesome TAs: cs109 @ cs.stanford.edu

Schedule Week 8
Date Lecture Outside Class
Mon, Nov 28th Logistic Regression PSet 6 out
Wed, Nov 30th Deep Learning
Fri, Dec 2nd Ethics
Pset 6: Machine Learning
2022112815 by the Teaching Team

Problem Set #6 has been released and is due next Wednesday (Dec 7th). In this pset, implement two core machine learning algorithms and apply them to real world datasets. Hope you enjoy.

Pset 5: Uncertainty Theory
2022111115 by the Teaching Team

Problem Set #5 has been released! Explore the beauty of the central limit, and more. It isn't due for 19 days, but that is because we don't expect you to have to work over Thanksgiving. Get started early so that you have no work over break!

CS109 Challenge!
2022110715 by the Teaching Team

One of the joys of probability+programming is the ability to make something totally of your own creation. In CS109 this quarter we are hosting a Challenge where you can make anything you like using the concepts and tools we learn in class. See the Challenge handout for more details.

Proof of CLT
2022110715 by the Teaching Team

The CLT says that if $Y$$Y$ is the sum of $n$$n$ iid random variables (which all have expectation $\mu$$\mu$ and variance ${\sigma }^{2}$$\sigma^2$) then:

$Y\sim N\left(n\mu ,n{\sigma }^{2}\right)$$Y \sim N(n\mu, n\sigma^2)$

The proof is beyond the scope of the class. A friendly CS109 student from a few quarters ago (Sophia Furfine) made a video of the proof in case you are curious!

Pset 4: Probabilistic Models
2022110215 by the Teaching Team

Problem Set #4 has been released! Explore Biometric Keystrokes, WebMd, Thompson Sampling and more.

Midterm Next Week
2022102414

Our midterm is coming up (next Tues and Wed). Want to know where the midterm is? Want to find practice problems? Want to know what is covered? Find all your answers and more on the: midterm page. The best way to study is to practice! 🎯

Chose your midterm time!
2022102113

The midterm is coming up. Because of the number of midterms on that same day we are going to offer two sittings of the CS109 midterm. Tuesday (Nov 1) at 7p and Wednesday (Nov 2) at 8p. We need a head count to make sure we have enough seats for both. All students should fill out the form here: Midterm Time Form (with the exception of SCPD students who use proctors)

Pset 3: Random Variables
2022101713 by the Teaching Team

Problem Set #3 has been released! It uses real probability density functions from the IPCC Climate Change report, create algorithmic art, and analyze a bloom filter (a probabilistic datastructure). Warning: the "extra long extension" for this pset goes until the night before the midterm, which is only 3.5 days.

Pset 2: Core Probability
Updated 2022101113 by the Teaching Team

Problem Set #2 was released last Friday and is due next Monday, Oct 17 at 2:15pm Pacific. Submissions are automatic via the PsetApp. Build a foundation of core probability theory.

Errata: an old version of this post mentioned Gradescope, which we no longer need

Sign up for section

Section is a core part of CS109. Sign up for section by filling out this form:
https://forms.gle/RDkKrXsjSs4DwRhD7
It is also a chance for you to tell us about yourself!

For more info on section, visit the Section part of the course syllabus. We are going to find the best weekly time for everyone. Section signups will close on Sunday, Oct 2nd at noon Pacific. Preferences are not first come first serve.

First Day of Class!

Welcome to CS109! We are looking forward to a fun quarter. Class starts Monday, Sept 26th at 3:00pm PT. We are looking forward to a great quarter 🌱.

What is CS109?

The Syllabus page has details on course logistics.
The Schedule page has a list of all topics that we will cover in CS109.

CS109A ACE
2022092610 by Julia

CS109A, also known as CS109 ACE, is a 1-unit supplementary section designed to build a stronger foundation in computer science. CS109A is a Computer Science department program based on one of the School of Engineering’s Equity and Inclusion Initiatives. Students participating in ACE will attend an additional weekly section and participate in exam review sessions and individual tutoring. We limit enrollment to enable small classes that allow students to have one-on-one interactions with the CA. If you are interested in joining the ACE section, please use this form: online application. If you have any questions about ACE, feel free to reach out to Julia Kadie (CS109A ACE CA) at jkadie@stanford.edu.

RESOURCES

Discussion
Course Reader
Syllabus
Schedule
Recordings
Office Hours

Key Dates

Midterm: Nov 1st, 7p
Final: Dec 13th, 8:30a
Last lecture: Dec 7th

Course Values

Everyone is welcome. Intellectual joy. Be kind. Be humane. Social connection. Learn by doing. Thrill of building. Adapt to new contexts. Especially in a hard time 🦠.

CS109: Probability for Comp. Science
Fall 2022, MWF 3:00pm - 4:20pm, Nvidia Aud.

Week 9 TODO

Finish your Challenge
Start PSet 6

Teaching Team

Professor: Chris Piech

RESOURCES

Key Dates

Midterm: Nov 1st, 7p
Final: Dec 13th, 8:30a
Last lecture: Dec 7th

Announcements

Schedule Week 8
Date Lecture Outside Class
Mon, Nov 28th Logistic Regression PSet 6 out
Wed, Nov 30th Deep Learning
Fri, Dec 2nd Ethics
Pset 6: Machine Learning
2022112815 by the Teaching Team

Problem Set #6 has been released and is due next Wednesday (Dec 7th). In this pset, implement two core machine learning algorithms and apply them to real world datasets. Hope you enjoy.

Pset 5: Uncertainty Theory
2022111115 by the Teaching Team

Problem Set #5 has been released! Explore the beauty of the central limit, and more. It isn't due for 19 days, but that is because we don't expect you to have to work over Thanksgiving. Get started early so that you have no work over break!

CS109 Challenge!
2022110715 by the Teaching Team

One of the joys of probability+programming is the ability to make something totally of your own creation. In CS109 this quarter we are hosting a Challenge where you can make anything you like using the concepts and tools we learn in class. See the Challenge handout for more details.

Proof of CLT
2022110715 by the Teaching Team

The CLT says that if $Y$$Y$ is the sum of $n$$n$ iid random variables (which all have expectation $\mu$$\mu$ and variance ${\sigma }^{2}$$\sigma^2$) then:

$Y\sim N\left(n\mu ,n{\sigma }^{2}\right)$$Y \sim N(n\mu, n\sigma^2)$

The proof is beyond the scope of the class. A friendly CS109 student from a few quarters ago (Sophia Furfine) made a video of the proof in case you are curious!

Pset 4: Probabilistic Models
2022110215 by the Teaching Team

Problem Set #4 has been released! Explore Biometric Keystrokes, WebMd, Thompson Sampling and more.

Midterm Next Week
2022102414

Our midterm is coming up (next Tues and Wed). Want to know where the midterm is? Want to find practice problems? Want to know what is covered? Find all your answers and more on the: midterm page. The best way to study is to practice! 🎯

Chose your midterm time!
2022102113

The midterm is coming up. Because of the number of midterms on that same day we are going to offer two sittings of the CS109 midterm. Tuesday (Nov 1) at 7p and Wednesday (Nov 2) at 8p. We need a head count to make sure we have enough seats for both. All students should fill out the form here: Midterm Time Form (with the exception of SCPD students who use proctors)

Pset 3: Random Variables
2022101713 by the Teaching Team

Problem Set #3 has been released! It uses real probability density functions from the IPCC Climate Change report, create algorithmic art, and analyze a bloom filter (a probabilistic datastructure). Warning: the "extra long extension" for this pset goes until the night before the midterm, which is only 3.5 days.

Pset 2: Core Probability
Updated 2022101113 by the Teaching Team

Problem Set #2 was released last Friday and is due next Monday, Oct 17 at 2:15pm Pacific. Submissions are automatic via the PsetApp. Build a foundation of core probability theory.

Errata: an old version of this post mentioned Gradescope, which we no longer need

Sign up for section

Section is a core part of CS109. Sign up for section by filling out this form:
https://forms.gle/RDkKrXsjSs4DwRhD7
It is also a chance for you to tell us about yourself!

For more info on section, visit the Section part of the course syllabus. We are going to find the best weekly time for everyone. Section signups will close on Sunday, Oct 2nd at noon Pacific. Preferences are not first come first serve.

First Day of Class!

Welcome to CS109! We are looking forward to a fun quarter. Class starts Monday, Sept 26th at 3:00pm PT. We are looking forward to a great quarter 🌱.

What is CS109?

The Syllabus page has details on course logistics.
The Schedule page has a list of all topics that we will cover in CS109.

CS109A ACE
2022092610 by Julia

CS109A, also known as CS109 ACE, is a 1-unit supplementary section designed to build a stronger foundation in computer science. CS109A is a Computer Science department program based on one of the School of Engineering’s Equity and Inclusion Initiatives. Students participating in ACE will attend an additional weekly section and participate in exam review sessions and individual tutoring. We limit enrollment to enable small classes that allow students to have one-on-one interactions with the CA. If you are interested in joining the ACE section, please use this form: online application. If you have any questions about ACE, feel free to reach out to Julia Kadie (CS109A ACE CA) at jkadie@stanford.edu.

Course Values

Everyone is welcome. Intellectual joy. Be kind. Be humane. Social connection. Learn by doing. Thrill of building. Adapt to new contexts. Especially in a hard time 🦠.