In Data 140 you will be learning probability based on your knowledge of math. Your work will consist mostly of math, with some computing to enhance your understanding of the math and also to point to interesting mathematical avenues to explore.

The programming prerequisite is Data 8, nothing more. The code will not be long or complicated. But you’ll have to figure out what to code and what its logic should be, based on the math.

**The key to success in Data 140 is logical clarity and math.** Students who have greater mathematical fluency have an easier time. They can focus more on the probabilistic concepts because the math and hence the course takes them less time.

Students don’t always know what faculty mean by terms like “mathematical maturity” or “math fluency”. I’ve tried to explain what I mean by math fluency in Data 140 and Stat 134, the upper division probability courses that I have taught, here. You’ll see that it’s less about the set of results that you know and more about how you understand what you do know and how you approach math.

**You don’t need math beyond what’s listed in the requirements. But you do need to be confident with all those requirements so you can use them at speed and follow the textbook.** Or you should be prepared to spend time learning math while you learn the probability. Many students do the latter but it’s very hard work.

If you’re worried that you don’t have the necessary fluency, the Math Prerequisites page includes the math needed for different parts of the course, some concise reference materials, and some exercises for you to try.

Student experience is unsurprising – if you take the page seriously and study the prereqs before the sections in which they are needed, it will be easier for you to pick up the new probabilistic concepts and do your assignments.

For many students, Data 140 is their first time doing math at the upper division level. There’s a learning curve that can be quite steep at the start, especially because the course involves both math and computing. The staff and student tips below will help.

Each term, the official course evaluation form ends with the question, “What advice would you give to another student who is considering taking this course?” I always post typical answers from the previous semester so that the advice reaches the right people.

I normally show the entire set on the first day of class, but in this unusual semester I won’t take the time for that. So let’s start with the complete set of responses that recommend against taking the class. The last one is thoughtful about the diversity of students’ math backgrounds.

- “Don’t.”
- “You will be destroyed.”
- “If you are not in the US, do NOT take this class until you can ensure you may attend live sessions.”
- “Do not take this class unless you are in a good timezone.”
- “If you have a decent mathematical background I think it will be a rewarding experience. Would 100% recommend. But with that said, if you don’t, perhaps be mindful about what you’re taking on.”

Now for a selection of all the rest. The response rate was about 56%, without added incentives for submitting evaluations.

This one is long but it summarizes the vast majority of student opinion.

- “To quote a review I read for CS61B that applies here as well: “once the bleeding stops, you’ll realize you learned something.” The course demands a lot of time and consistent effort on the part of the student and moves at an aggressive pace, but it is incredibly well–organized with plenty of resources to help students succeed. The textbook and lectures were highly effective in conveying the concepts, and discussions covered very relevant material and served as bridges between seeing the material in lecture and applying it to the homework. Office hours were an indispensable resource as well. It was a very painful class, but that pain is directly proportional to how consequential the material is to Data Science and how much the student gets out of it. It is well worth the investment, but only if you put the work in.”

For more details, here are some other voices all telling it like it is. Staff and former students will confirm that they’re similar to responses in past semesters.

- “Stay on top of coursework, cramming at the last second is impossible. Go to discussions, exam questions are very similar. Do all the chapter exercises, exam questions are very similar to those.”
- “STAY ON TOP OF THE MATERIAL!”
- “It’s probably impossible to do well in this class if you don’t stay up to date on the material – just go to lecture on time and do most of the recommended exercises, and all will be fine.”
- “Read. The. Textbook. Make sure to stay up to date with the course content or it’ll start becoming incredibly difficult to catch up, and even get started on upcoming assignments.”
- “In most classes, the professor will have ‘recommended reading’ in the textbook and you will probably ignore them. There’s no need to do that in this class because the textbook is actually incredible and will tell you everything you need to know if you read it carefully.”
- “Attend lectures, even if the textbook provides everything you need to know content–wise!”
- “Go to lecture and discussion and OH!! Do the practice problems, they’re a big reason why I did decently on exams.”
- “Attempt problem sets on your own before collaborating with others.”
- “Go to office hours and keep asking questions if you aren’t sure about something! ALSO, GET A FRIEND. This class was incredibly tough (a lot more difficult than I expected) … but after I found a friend to work with/struggle with, I felt A LOT better about how I was doing in the course.”
- “Take a lighter course load. Ask yourself if you’re ready to put in the many hours and discipline this course requires … This course is really cool, and when I understood a concept, it was one of my favorite feelings. However, it is hard, and it requires a lot of time and focus and energy.”
- “This course requires grit. If you’re feeling ambitious, go for it. Focus on learning and understanding the material, not on getting an A. If you’re really passionate about learning, grades will follow.”
- “You get from this course what you put in … This class should definitely be your top priority for the semester. That being said, if you put in the required work, it will be worth your effort!”
- “Take it. And if you do, don’t be a lazy linguini. Put in the work and you’ll get results promise.”
- “Prepare for hard work and frustration, but in the end, you will see how much you’ve improved.”
- “I am taking this course as a senior and I just want to say that I am so happy that I did. Most of my other classes are challenging but prob140 is one of the few ones that I felt like my intellectual capacity got expanded.”
- “Stay confident!”
- “Don’t underestimate the course, and don’t underestimate yourself.”

If you think this might not be for you this semester, the About page lists other upper division probability classes you can take. They’re all terrific. Be aware though that none of them is an easy ride. For example, student recommendations about Stat 134 often include tips to join the adjunct class at the Student Learning Center, which in effect is advice to spend more time on practice.

Students who want to take 140 after strengthening their math beyond the prerequisites often ask what math class they should take as preparation. Almost invariably my answer is that they should take any math class numbered in the 50s or higher. All math classes make you better at doing math.

I think it’s better to prepare by taking more math instead of lower division probability as in Stat 88. Math skills will have more general applicability and will help more with the second half of 140.