Two big things!

We published Quiz 3 grades, and we just now shared the Quiz 3 solution right here! We're very close to publishing final grades to Axess, and we'll likely do so this coming weekend.

More importantly, we want to share with you the names of the three students who submitted CS109 Challenge projects that were so stellar that Chris and Jerry decided to certify all three as Grand Prize winners. In no particular order, the Grand Prize Winners are:

• [video][written report] Emily Jin studied the effects of the COVID pandemic on education! [Note: I know the video link is dead, and I've reached out to Emily to see if it can be fixed.]
• [video][written report] Jaden Clark implemented Kalman filtering to improve a robotic race car's ability to estimate its distance away from a collection of obstacles!
• [video][written report][website] Miles McCain leveraged CS109 material to build CAPTCHAs that foil humans but not robots. Future CS109 problem set question!

The Center for Teaching and Learning is seeking applications from students interested interested in part-time work as a CS109 tutor during the 2021-2022 school year. If you're eager to gain some teaching experience and you'd like to be considered, email Jerry directly and he'll let Alex Ayers—she runs the tutoring program— that you're interested so she can reach out.

The last quiz is live. You have until Friday, March 19th at 11:59pm AOE (4:59am on Saturday pacific time). AGAIN 🌱 WE 🌱 HOPE 🌱 YOU 🌱 HAVE 🌱 A 🌱 GOOD 🌱 TIME 🌱 AND 🌱 LEARN 🌱 A 🌱 LOT 🌱 ALONG 🌱 THE 🌱 WAY!!! YOU 🚀 WILL 🚀 DO 🚀 GREAT! Best of luck!

Former CS109 student Kevin Ji was in touch about an opportunity that might be of interest to those jazzed by CS109 material. Here's what he said:

Problem Set #6 has been released and is due next Wednesday (March 17th). There is no late submissions for this last pset since it is the end of the quarter. This March 17th deadline is simultaneously the on-time-with-bonus deadline and a hard deadline as well. In this pset, implement two core machine learning algorithms and apply them to real world datasets. Hope you enjoy.

An earlier announcement mentioned that WiCS is holding a few open-to-all study sessions this quarter, and the last two of them are being held over the course of the next week. The first of the two is this Wednesday, March 10^th at 5:00pm, and the second is a week from today, on Sunday, March 14^th, also at 5:00pm. You're more than welcome to attend either or both sessions, but the March 14^th session is being advertized more specifically to CS109 students. The Nooks link for both sessions is right here.

Everyone! All quizzes have been fully graded as of about ten minutes ago, so you should be able to see your quiz over on Gradescope. The median grade was an 85 (amazing!), the mean was just above 81, and the standard deviation was an 11.3. We were particularly impressed with all of the clean and creative answers to Question 4, which was a very, very difficult problem!

Great work, everyone!

The second quiz is live. You have until Saturday Feb 27th at 2:30p to complete it. WE 🌱 HOPE 🌱 YOU 🌱 HAVE 🌱 A 🌱 GOOD 🌱 TIME 🌱 AND 🌱 LEARN 🌱 A 🌱 LOT 🌱 ALONG 🌱 THE 🌱 WAY!!! YOU 🚀 WILL 🚀 DO 🚀 GREAT! Best of luck!

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

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!

Problem Set #5 has been released! Explore Biometric Keystrokes, Ethics, Fairness, Titanic Probabilities and more.

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.

Problem Set #4 has been released! Explore Biometric Keystrokes, Ethics, Fairness, Titanic Probabilities and more.

This just in from CS109 graduate, Hannah Zhang: Stanford Women in Computer Science (WiCS) is holding a study night for CS 109 and a few other CS classes on Wednesday, February 10 at 5PM PST. All genders are invited!! We’ll be providing you all with a casual space to study with your peers and raffling off a few gift cards :) The Nooks link for today's session is right here.

In an earlier email, Hannah mentioned they're be future study sessions on February 21, March 10, and March 14, and that the February 21 and March 14 dates are specifically set up to host CS109 students and students from a few other classes. (But you're welcome to join any and all of them!)

The first quiz is out. Use this link to download the questions: quiz1. You can also find in under the quizzes drop down menu! You have until Friday at 1pm (Pacific Time) to submit it. As Jerry said this morning 👏YOU👏 ARE👏 GOING👏 TO👏 BE👏 AWESOME👏!!!!!! Best of luck!

Problem Set #3 has been released! It uses real probability density functions from the IPCC Climate Change report, has you predict elections and analyze a bloom filter (a probabilistic datastructure).

Problem Set #2 was released last Friday and is due next Monday, Feb 1 at 1:00pm Pacific. Submission will be via Gradescope. Build a foundation of core probability theory.

Alex Ayers runs the peer-tutoring program at the Center for Teaching and Learning, and he emailed Chris and Jerry a few minutes ago and mentioned that peet tutoring available for CS109 and other introductory CS courses (CS103, CS106B, CS107, and CS110 are likely the be of interest to many of you). Alex wrote: "Want to meet with an experienced peer to discuss course concepts, think through a problem set, or prepare for an upcoming exam? CTL offers appointment tutoring for CS 109, in addition to tutoring for a number of other courses. For more information and to schedule an appointment, visit our tutoring appointments and drop-in schedule page. We also have a variety of remote learning resources and academic coaching available to assist with all of your learning needs! "

Today is the first day of sections! You should have received an email yesterday with your section time and the name of the TA who will be leading section. You can find the zoom link for your section on the staff section and office hour page (find your TA in the list and look for a link titled "section zoom"). If you didn't receive an email, please contact Tim (tgianit@). Section is an key component of your learning — wahoo.

You can find section materials in the "Section" tab. Here is the link for Section 1. We will post solutions after section!

Reminder that today, Jan 18th, is MLK day so there will be no classes or office hours

Here is a video of the last public speech MLK gave. The date was April 3, 1968 and he was assassinated the day after. Civil rights for all people, regardless of their ethnicity, is a cause that is still being fought for around the world.

If you haven't recently seen the I Have a Dream Speech, that is worth watching for its beautiful narrative and its influence on history. In 1967 MLK gave a speech at Stanford where he directly addressed students and faculty.

A fellow CS109 student, Jennifer John, emailed us to identify a mentorship program that matches freshmen and sophomores interested in CS with upperclassmen BSCS majors. Applications are currently open, and Jennifer asked that I post the descriptions of ideal mentor and mentee candidates.

• Mentees
• Are you interested in pursuing computer science at Stanford, but have questions about choosing classes, starting research, or balancing CS with other interests? An experienced upperclassman could help you kick-start your CS journey! The CS Undergraduate Council is excited to announce that applications are now open for the Winter Quarter Mentorship Program. As a mentee, you'll get to meet with an older CS student 1:1 several times during the quarter to chat about absolutely any questions you have about CS at Stanford. You'll also join a supportive community and attend helpful events. Applications are due January 27, and spots are limited, so apply now! Note that you must be a frosh or sophomore to apply. Please reach out to Jennifer John with any questions.

• Mentors
• Want to give back to the undergraduate CS community by mentoring an underclassman? The CS Undergraduate Council is excited to announce that applications are now open for the Winter Quarter Mentorship Program. As a mentor, you'll meet with a frosh or sophomore who's interested in CS several times during the quarter to share your experiences navigating the major. You'll develop leadership skills and volunteer experience and contribute to making CS at Stanford more inclusive. Applications are due January 27. Note that you must be a sophomore, junior, senior, or coterm to apply. Please reach out to Jennifer John with any questions.

Section is a core part of CS109. Sign up for section by filling out this form:
https://forms.gle/NPp1wyGUt86dzrKT6
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 Saturday, Jan 16 at 11:59pm Pacific. Preferences are not first come first serve. If you are living in a different timezone, we wrote a Stanford timezone conversion tool to convert Stanford Time listings to your home timezone.

The first of three Python help sessions will be held this Friday, Jan 15 3:30pm Pacific Time. These times are on the CS109 calendar and you can join the session at the zoom link on the calendar (to be posted closer to the date). Please make sure you have installed or attempted to install Python per this website guide to Python. During the session we will be covering Python language basics, important Python libraries, and get you set up to start Problem Set #1. There will be a Q&A and debugging setup session at the end. The meeting will also be recorded and posted on Canvas after the fact for those who cannot make it live. Looking forward to seeing you all there!

Problem Set #1 has been released! It is due next Friday, Jan 22 at 1:00pm Pacific. Submission will be via Gradescope with entry code P5W3BR. Office hours will start today, and the office hours calendar will have times and Zoom links.

You are encouraged to write up your problem sets using LaTeX. Templates for each Problem Set are located on their respective webpage. See this installation guide and intro to LaTeX. Though you may install LaTeX, it is often much easier to use an online LaTeX editor. A great option is: overleaf.com. In pset 1 you will be doing some pretty advanced counting

CS109A, also known as CS109 ACE, is a new, 1-unit supplementary section designed to build a stronger foundation in computer science. Students participating in ACE will attend an additional weekly section and participate in exam review sessions and individual tutoring. During week 1, section will take place on Thursday 10am-11:20am Pacific on Zoom, synchronously.

CS109A ACE is a Computer Science department program based on one of the School of Engineering’s Equity and Inclusion Initiatives. We especially want to provide an opportunity for students who come from educationally disadvantaged backgrounds or for anyone who feels they might need additional support in order to succeed. 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. We will accept applications through January 15th. Students who apply by January 13th will be welcome to attend section the first week and will receive a Zoom link for section via email during Week 1. If you have any questions about ACE, feel free to reach out to Georgia Sampaio (CS109A ACE CA) at gsamp@stanford.edu.

The very first CS109 Winter 2021 lecture is at 1pm today, Monday Jan 11th. Come 10 mins early if you would like. You can find the zoom link here (you will need to sign in though webauth): lecture zoom

Welcome to CS109! We are looking forward to a fun quarter. Class starts Monday, Jan 11th at 1:00pm PT Online. Section enrollment details will be released on the first day of class; you do not need to enroll via Axess. We are looking forward to a great quarter 🌱.