DATA400 | PlanetTerp

Information	Review
Jonathan Fernandes DATA400 Expecting an A Anonymous 05/30/2025	If you do the work, you should be able to get an A. I initially struggled, but once I found the rhythm of the course, it became much easier. He provides sample questions for the exams - which are based of homework and the examples he covers in class. While he will not provide a solution manual for these problems, if you keep up with the work, it is not hard to find the answers in his notes. Also his exams are not the practice exam with numbers changed, so be careful about that. He expects you to work through all of the content covered in lectures! I did not find the final exam particularly hard, as most of it was based off what was done in lectures and discussion ... but this could just be me. I did study a lot for it though. All in all, I found this to be a useful class, and if you have the chance you should take it with Fernandes. You might have to work some, but you will learn a lot!
Jonathan Fernandes DATA400 Expecting an A Anonymous 05/21/2025	On the whole I would recommend this class. It is a hard class, and he expects you to work on the content. People say Stat400 is an easy A, but it was not the case for me. I did have to put a lot of effort, and the class is generally well supported - with him going over concepts and examples during lecture, and TAs working on homework problems. Somehow he has really cool TAs who go out of their way to help you! He has in-person quizzes during discussion - which I did not particularly like, but he allowed for students to take make-ups within a week if they missed any. Just because of this I would take one star off, but then the 1-star review below me (from 05/20/2025) is flat out lying to the point that I am wondering if this person was somehow going to a different lecture all all semester long - so will give 5 stars!
Jonathan Fernandes DATA400 Expecting an A Anonymous 05/21/2025	As someone who struggles with math and statistics, this course truly helped me appreciate both the mathematical background and the practical intuition for many of the concepts that were thought ... while I found most of his lectures very engaging, I particularly liked the way he explained bayes theorem. The lecture on covariance and linear relationship was fun too ... if you connect with his style and humor, the lectures are pretty nice and worth going to. His exams, especially the final is admittedly hard ... but he covers all the content and solves many of the problems during lecture and discussion (he has some of the most amazing TAs!!!). If you go to lectures and redo the examples from there, and the discussion, you should have no problem with the exams. Also, he adjusts the grades at the end of the semester and allowed for one homework resubmission, so as long as you are consistent with your work, you will be good! He also records all his lectures, and live streams his notes ... which was very helpful for me.
Sana Jahedi DATA400 Expecting a B+ Anonymous 05/08/2025	Never in my college experience have I come across a group of people who don't know that they don't know, take no responsibility, and then shit talk the instructor like they know better how to teach the class. If you ever want to know experimental evidence of the Dunning Kruger Effect, take Stat400. Of course, Prof. Jahedi has their shortcomings like any other human would, however, trying to blame and cyber bully her over here when you could talk to her in person and get the feedback you need, even if it means you need to work on your study habits (mind you, the semester is yet to be over!) is the very reason why the educational system in the US is focussed on customer service than actual learning!
Sana Jahedi DATA400 Expecting a B Anonymous 05/06/2025	The reviews here are the reason why we don't deserve good things - downright cyber bullying!!! She is not that bad, and does genuinely put effort in her teaching. While the class is hard, many will come in expecting to get an A with minimal effort sometimes taking with over 15credits of coursework. It is not an easy class! Using PlanetTerp to harass an instructor, only decreases the credibility of this website! I sometimes worry about the dumbass impression about UMD students that these reviews convey to those outside of UMD (some reviews here downright complaining that this was not an easy A they hoped for, lol) , and god forbid my prospective job interviewers.
Sana Jahedi DATA400 Expecting an A+ Anonymous 05/05/2025	took sana's data400/stat400 class in fall 2024. it was probably my class' fault that the class is so bad now; people would constantly abuse the extremely generous grading and retake system to the point she had to take it away (including straight up leaving after putting their name down during group quizzes), people would gossip and talk in class at regular talking volumes while paying zero attention to sana to the point where she got fed up and sometimes asked students themselves to come up and explain topics for extra credit, and people would openly brag about how they didn't know the content and just memorized the practice exams WHILE IN CLASS/IN FRONT OF HER to the point where she just gave up and put the easiest problems from the problem pool on the final. all of that might be completely justified: why not get the most out of the retake system before its gone? if the lecture wasn't helping you, why not just ask a friend what was going on during class? if the best way to get an A was to memorize, why not just do that? but i think people went about it in such a disrespectful way that fall 2024 was genuinely an awful experience for sana very early on in her lecturing career and probably the reason she is so spiteful/'mean' this semester.
Sana Jahedi DATA400 Expecting a D+ Anonymous 05/04/2025	I took STAT400 with Sana Jahedi, assuming it would be fair based on PlanetTerp. I was so wrong - despite Sana's smug lecture on how everything is "fair" and it was "all our fault." Let’s start with the facts: Sana is clearly knowledgeable (I'd hope considering she has had a lot of education), but she teaches like she’s trying to keep the secrets of probability secret. Her lectures often feel like you're walking into the middle of a conversation that started without you — and also maybe in another language. Concepts that could be explained with a simple example are instead buried under abstract generalizations and chalk dust. Office hours? Yes, they exist. Will they help? Debatable. Exam prep? There are no practice materials, and the exams themselves love throwing in curveballs and notation you've never seen before — like a pop quiz on a different course. Honestly, I’m just glad Sana’s PlanetTerp rating is now just as low as her exam averages. Balance has been restored to the statistical universe.
Sana Jahedi DATA400 Expecting an A- Anonymous 05/04/2025	his class has been a mental marathon with no water stations. Sana’s lectures feel more like TED Talks than actual lessons—lots of abstract musings and philosophical tangents, but very little in the way of concrete, step-by-step instruction. The notes are a cryptic mix of bullet points and vague definitions, and we’re expected to reverse-engineer the logic behind them on our own. She says the exams are “straightforward” but then throws curveballs that feel like grad-level trick questions. You know it’s bad when the homework feels hard and the exams feel worse. And don’t bother asking for clarification—she rarely entertains follow-ups, and when she does, the answer usually makes things more confusing. There’s no review session, no sample questions, no guidance. If you do poorly, the response is always, “Well, I thought it was fair.” There’s no acknowledgement of any disconnect, just this unshakable insistence that we’re all just not trying hard enough. Honestly, I’ve never felt more gaslit by a class.
Sana Jahedi DATA400 Expecting a C- Anonymous 05/03/2025	Her lecture problems, quizzes, and homework vary in difficulty, but the exams are significantly harder than any other assessment. The material covered in lectures does not align well with the content or difficulty of the exams or any other graded assignments, making it extremely difficult to prepare. She does not provide practice problems for the midterms, and despite low exam scores, she takes no accountability—refusing to offer a curve and instead placing the blame on students. This class has had a severe negative impact on my GPA. I regret not choosing a different professor, as her final semester of teaching felt intentionally harsh.
Sana Jahedi DATA400 Expecting a B+ Anonymous 05/02/2025	Hi Sana. I know you read these. So let me just say: respectfully, this class is statistical warfare. Every time you said “This one’s not too bad,” I knew pain was coming. You’d write 4 lines of gibberish on the board like that meant anything to anyone in the room. It wasn’t obvious. I did every homework. I went to every lecture. I still felt like I was guessing on the exams like it was a personality quiz: Please consider updating your exams so they resemble what you actually teach. Or at least warn us that the exam would actually be the end of us. Anyway, keep a look out for my therapy bill in the mail. Sincerely, A Survivor.
Sana Jahedi DATA400 Expecting a B Anonymous 05/02/2025	The quizzes lull you into a false sense of security. Then the exams come in like a jump scare. Stat400 with Jahedi is a rite of passage. Like parallel parking or assembling a fan from Amazon — painful, but you grow from it.
Sana Jahedi DATA400 Expecting an F Anonymous 05/02/2025	I really wanted to enjoy STAT 400 after reading great reviews of Professor Sana, but this class has been a struggle. In lecture she often speaks without a microphone, and I find myself straining to hear the key ideas. Instead of walking us through examples, she’ll share personal stories or life advice—great in small doses, but it leaves us scrambling when it’s time to learn the material. When she does dive into statistics, it’s at lightning speed. I’ve lost track of how many times I’ve raised my hand only to see the lecture move on without checking if we understood. Early on she promised that a strong Quiz 2 score would replace our Quiz 1 grade, but that rule was quietly withdrawn later in the term. That kind of last-minute change really shook my confidence. I also wish we had more concrete practice. There’s no sample midterm or review sheet, so it’s tough to judge pacing or question style when the actual exam time arrives. Some homework questions feel vague or unlike anything we covered in class, and when I post on Piazza, I get the participation credit—but the real answers often don’t come until much later, if at all. I know every instructor has a different style, and I appreciate that Professor Sana wants to connect on a personal level. But for me, the balance has tipped too far away from clear, step-by-step teaching. If you learn best with guided examples, regular check-ins on understanding, and plenty of practice materials, you might find this section of STAT 400 frustrating.
Sana Jahedi DATA400 Expecting a B- Anonymous 05/02/2025	For the Spring semester, Sana decided to change up how she ran STAT400 class. Do not trust the reviews from before Spring 2025 because the class has fundamentally changed. The gap in difficulty between different parts of this course is jarring. The content in the homeworks and discussions are sometimes out of the lecture's scope, yet Sana expects her students to be able to extrapolate concepts from the lecture and apply them to harder questions (questions that we've never seen before). She's expecting her students to solve problems on her exams (problems that also barely show up in lectures/discussions/homeworks) as she intended and with a specific line of intuition. Unfortunately, most students taking this class don't have that kind of intuition, and at the very least, there should have been more practice problems and explanation. Instead, the two exams we've taken so far feel far more difficult than the quizzes we get. I don't recommend taking this professor, especially if you need to fulfill your major requirements. The professor asks alot for people who aren't aspiring staticians.
Sana Jahedi DATA400 Expecting a B Anonymous 04/29/2025	Just horrible. Last semester she great according to reviews due to her very student friendly polices. Yeah none of those exist anymore. She essentially gives 0 study material. You're supposed to use your discussion worksheets and homework as your study material. She is rude, mean and condescending. She acts like students are just there to waste her time. This past exam was possibly the worst exam I have taken at UMD and I would not be shocked if the average is sub 60. In class she essentially blamed all of us for not studying enough and said that it was our fault. So if you take her you are dealing with someone that has 0 accountability. Her lectures are completely a mess and make 0 sense most of the time. I guess she has decent slides that will kinda help you understand the material, but that does not help you at all on the exams. Do not be fooled by past reviews, take anybody else! I could keep going on and on but I think you get the point. Save your GPA and take anybody else
Sana Jahedi DATA400 Expecting a D+ Anonymous 04/25/2025	I genuinely didn’t know a person could be this bad at teaching and still be employed. Her lectures are incoherent, her attitude is trash, and her exams are rage-inducing. The only consistent thing about this class was the suffering.
Sana Jahedi DATA400 Expecting a D+ Anonymous 04/25/2025	If I could rate her zero stars, I would. Actually, negative stars. This class takes away knowledge. I came in knowing some things, and now I know less. A void has opened where my brain used to be. Thanks, Sana.
Sana Jahedi DATA400 Expecting a D Anonymous 04/25/2025	This class made me reconsider my entire major, my career path, and whether humanity deserves education. I walked in optimistic. I walked out emotionally bankrupt. She doesn’t teach — she torments. Save yourself.
Sana Jahedi DATA400 Expecting a B Anonymous 04/25/2025	Nothing prepares you for this class — not the lectures, not the practice problems, not even divine intervention. She gives you study material, then tests you on something completely different and acts like you should’ve known better.
Sana Jahedi DATA400 Expecting an A- Anonymous 04/25/2025	This professor is a disgrace to education. I have never encountered someone so unqualified, unhelpful, and outright cruel in a position of power. The midterms were a complete joke — not even remotely related to the practice problems or lectures. It’s like she went out of her way to make the test as confusing and convoluted as possible, just to flex her ego while watching students fail. She does not care. Not about teaching, not about students, not about anything but hearing herself talk. Every interaction feels like you're being talked down to by someone who thinks empathy is a weakness. Asking questions? You're treated like an idiot. Asking for clarity? You're met with attitude and passive aggression. This isn’t just a bad class — it’s emotional whiplash. She’s condescending, detached, and deeply unpleasant. I genuinely believe she gets satisfaction from watching students suffer. This was not just frustrating — it was demoralizing. Her attitude is toxic, and her incompetence is astounding. If you value your time, sanity, or basic dignity, do not take this class. I wouldn’t wish this experience on my worst enemy.
Sana Jahedi DATA400 Expecting a C- Anonymous 04/25/2025	I don’t even know where to begin because this class was an absolute nightmare. The midterms were completely disconnected from the practice problems — as in, studying felt like a waste of time because nothing prepared you for the sheer randomness and cruelty of the exams. It honestly felt like she enjoyed watching students struggle. And don’t expect an ounce of understanding or humanity. This professor is cold, condescending, and completely checked out. She doesn’t care if you’re confused, doesn’t care if the whole class is struggling — she just keeps going like it’s your fault for not being able to read her mind. I’ve never felt so disrespected or demoralized in an academic setting. She has no business teaching, let alone interacting with students. It’s not just bad teaching — it’s actively harmful. This class drained my motivation and made me question why I even try. If I could give negative stars, I would. Run.
Sana Jahedi DATA400 Expecting a C Anonymous 04/25/2025	This professor is hands down one of the worst teaching experiences I’ve ever had. The midterms were completely disconnected from the practice material, almost like they were designed to trip you up rather than test your understanding. It’s infuriating to prepare based on what we’re told to study, only to be blindsided by questions that feel intentionally misleading or cruel. What makes it worse is the complete lack of empathy or support. Asking for help or clarification feels like an inconvenience to her. It’s honestly shocking how little regard she has for her students — academically and personally. She’s not just a bad teacher, she’s a deeply unpleasant human being to deal with. I wouldn’t wish this class on anyone. Avoid it if you value your GPA or your sanity.
Sana Jahedi DATA400 Expecting a B Anonymous 04/24/2025	can't teach. hws are harder. quizzes are not in groups anymore. does not provide a review guide for exams anymore bc students did too well -> exams are harder literally looked at her reviews and and said fuck u guys and made the class harder than it needs to be. generational fall off.
Sana Jahedi DATA400 Expecting an A Anonymous 12/30/2024	Highly incompetent and cannot speak English. She tries to cover her incompetence by being "sweet". Guess what? we are here to learn from someone who knows what they are doing. We do not come to have a "sweet" instructor who struggles in English and struggles in the material at hand.
Sana Jahedi DATA400 Expecting an A Anonymous 12/21/2024	She has no clue about data or stats. Not sure who gave her this course. folks go learn with someone else.
Sana Jahedi DATA400 Expecting an A Anonymous 12/16/2024	Sana is a very fair professor. Things to note: - Discussion had mostly group quizzes - When we don't have quizzes, there are ungraded worksheets, a great way to practice and ask questions from TAs if you need help. - Every discussion problem and homeworks have detailed solution that Sana spend time to provide. - We had only about 6 quizzes and 7 HW. - Everything thing that is graded or provided is fair and on level. (Homeworks and Exams). - Lectures are easy to follow. For those with ipads, she posts pre filled notes so taking notes are easier.
Jenna Zomback DATA400 Expecting an A Anonymous 12/14/2024	Zomback is the best math teacher I’ve ever had.
Sana Jahedi DATA400 Expecting an A Anonymous 12/14/2024	Shes very understanding and as long as u do the study guide youll do just fine on exams highly recommend her
Sana Jahedi DATA400 Expecting an A- Anonymous 12/11/2024	Her teaching in lecture wasn't my favorite, but she is very generous grader and offers very easy extra credit if you need it. She posts good notes and is great at explaining things in office hours. She also is very understanding and flexible if you ask her about anything.
Sana Jahedi DATA400 Expecting an A+ Anonymous 12/11/2024	Midterms went over EXACTLY what we learned in class, review practice problems, and discussion (also gives ANSWERS!! to all of them as well, so just remember how to do those and then you're good for the midterms). Posts notes after class and has a piazza for questions (she answers pretty quickly imo)
Sana Jahedi DATA400 Expecting an A+ Anonymous 12/08/2024	Very understanding teacher, exams are just like the study guide. An A is basically guaranteed as long as you go to class.
Sana Jahedi DATA400 Expecting an A- Anonymous 12/05/2024	exams exactly like practice tests not too hard. Very easy grader and super nice teacher.
Sana Jahedi DATA400 Expecting an A+ Anonymous 11/15/2024	She is one of the nicest professors and understands you. Offers help, her exams are just like the practice so if you get the hang of that you should be fine. She is also very sweet. quizzes and labs (which are like group quizzes) every week, you have about 7 of these a semester are super fair but attendance is mandatory in disscussions. 2 midterm exams 15% of your grade each. definately recommend her for stat 400.
Sana Jahedi DATA400 Expecting an A+ Anonymous 11/12/2024	She is one of the best stat teachers. She is super lenient, lectures well, gives fair quizzes, and there are a lot of team quizzes. 10/10 would recommend if you need to take this class.
Sana Jahedi DATA400 Expecting an A+ Anonymous 10/26/2024	Definitely one of the nicest professors I've ever had, especially if you meet her in office hours. She teaches the material really well, down to earth and always willing to follow on with you or meet you privately if you need help. Her exams are mostly easy and her work doesn't destroy you mentally because she gets that you have other classes and whatnot. Would definitely take her for this class.
Sana Jahedi DATA400 Expecting an A Anonymous 10/22/2024	She is the goat. Her practice exams is exactly like the exam. She's understanding and nice. Best prof I've had in MATH department, heavily recommend.
Sana Jahedi DATA400 Anonymous 09/27/2024	really good thumbs up emoji (I'm not writing a paragraph)
Fushuai Jiang DATA400 Expecting a C- Anonymous 07/16/2024	Do not take his class trust me. If this review saves one person it was worth it.
Jonathan Fernandes DATA400 Expecting an A Anonymous 05/21/2024	He is very nice and generous, but his curriculum and notes could be structured better.
Fushuai Jiang DATA400 Expecting an A+ Anonymous 05/16/2024	Dr. Jiang is not a good professor. He doesn't communicate with the TAs, all of his lecture content is directly out of the textbook (and he uses his own preferred textbook instead of the STAT400 standard book), and he answers questions in a usually confusing and occasionally condescending way. He's a nice guy and will help in office hours if you go, but he intentionally teaches this class at a very high difficulty compared to the other STAT400 teachers. Average on the first exam was ~55%. If you don't know a lot about proofs you will definitely struggle in the first half of the class, but even if you know proofs well its still very difficult. Exams are weighted: 20%, 20%, 40%, so pretty much they are the only important grades. This class would only get one star if not for the absolutely massive curve. Most people did really poorly on the exams so the curve was huge, so you might end up with a passing grade even though you didn't do well on the exam. Be prepared to put in a ton of time studying outside of class if you want to understand the content and do well on exams.
Jonathan Fernandes DATA400 Expecting an A Anonymous 05/01/2024	The class is so free– he gives 90% of the test material in the study guides for the test. Has a tendency to overexplain. Homeworks are challenging but help to prepare you for the test. Quizzes are bullshit but they're online and you have multiple attempts. Also, this guy does not respond to emails
Fushuai Jiang DATA400 Anonymous 03/03/2024	He writes notes, not that legibly, in notability, and fails to really explain any proof, and instead writes it word for word from the text book. There were times when people had questions, and he stated that "it was outside the scope of the course". His review problems for the test are not close at all to actual problems present on the test and instead are random proofs and questions he's taken over all his lecture. TA's are nice and are the only way to get through the course, but most of the time they have no idea what he's doing. You are allowed a cheat sheet on exams, but it only helps if you happened to copy the right proof down, or else good luck figuring it out intellectually on exams when you likely won't. Overall, take any other professor for STAT400, because they are all way better in terms of grade distribution and teaching ability. If you were forced to take Professor Jiang, then I wish you the best of luck, you'll need it.
Dmitry Dolgopyat DATA400 Expecting an A Anonymous 12/25/2023	Lectures are very difficult to understand, focuses too much on the underlying theory leaving you really confused on what he's trying to explain. 9 times out of 10, after self studying I realize that the content is actually not that hard, he's just not very good at explaining. Most people skip the lectures and do fine. His tests, quizzes, and homework are actually pretty reasonable and he is pretty generous about how they are graded. You can pass this class if you work hard, but I can definitely say there's easier professors to take.
Dmitry Dolgopyat DATA400 Expecting a B- Anonymous 12/19/2023	Clearly a very smart person and knows a lot about the subject. However, he is not meant to be a professor. I was lost in all of his lectures. Office hours were very difficult to figure out. His answer keys for reviews had a lot of errors and were hard to follow and understand. Not sure I really learned anything from this class. The fact that quizzes (30%) are worth more than exams (20%) is what got me a B-.
Jonathan Fernandes DATA400 Expecting a B+ Anonymous 12/18/2023	The first half of the semester really deceived me. Homework was doable, and the first exam was genuinely copy and paste the sample exam, even though we did not have access to a calculator. But then things suddenly shifted once the second exam came around. For the first exam, he went over the entire sample exam in class and discussion, for the second one, he only went over a few in class and the rest were just in the air. Mind you, these questions are a lot harder and it's tough to conceptualize without seeing an example of it. I had to go on a scavenger hunt to find answers, some were in lecture notes and others were found in homework answers. I even had to scan through answers from PREVIOUS YEARS to find close answers. The worst part is the second exam was not simply a copy and paste from the sample. Now here comes finals, he posts a sample exam with 36 QUESTIONS!!! and does the same thing he did for the second exam. He expects us to find answers & examples through his lecture notes and homework and all over. Overall a very frustrating exam experience. Knowing that his exams are derived from his samples (he even tells us this), it is all the more important to have some sort of answer sheet explaining some of these questions. The questions are typically one of a kind and were only mentioned once or twice on homework or lecture so often times students don't have a full grasp on how to apply their knowledge to such problems. He is overrated simply because he curves, but do not expect this class to be easy (don't let people fool you like they fooled me) TAKE MESTIYAGE, HE ALLOWS A CHEAT SHEET AND CALCULATOR!!!
Dmitry Dolgopyat DATA400 Expecting an A Anonymous 12/15/2023	I cannot say enough positive things about Mr. Dolgopyat. From the moment I stepped into the classroom, I knew I was in for an amazing semester. His passion for statistics was infectious and made me excited to learn. One thing that sets this teacher apart is their ability to make complex concepts easy to understand. They have a way of breaking down difficult material into manageable pieces, and their explanations are always clear and concise. His use of real-world examples and hands-on activities made the course material come to life and solidified my understanding of the subject.
Dmitry Dolgopyat DATA400 Expecting a C- Anonymous 11/22/2023	I just want to make something very clear first: Dmitry is clearly a brilliant man and knows what he's talking about... He's just not a very good lecturer. If you're going to take this class, I hope to you're comfortable with reading chapters out of a textbook to teach yourself, because that's all your semester will consist of. I stopped going to his lectures because I realized that teaching myself the material from the textbook was genuinely a more productive use of my time. Dmitry's midterm study material (practice exams) are a 50/50 when it comes to how similar they are to the actual exams (first midterm -- actual exam was easier than practice; second midterm -- actual exam was on par with practice in my opinion), so it's stressful to try and figure out whether it's over for you or not, while doing the practice exams. I'm the type of person to find the positive in every terrible situation, so I'll try to do the same here. You get weekly homework assigned to you on Webassign, and honestly, I'm always able to knock those out within around 1.5 to 2 hours, and the problems are straightforward enough such that you're able to read the textbook and (mostly) know what to do. Not only that, if you genuinely and honestly do well on the homework assignments, the weekly quizzes are easy, since they're pulled straight from the homework (albeit with different numbers). Yeah, that's it... Whoever you are reading this, if you're like me and took this class due to lack of openings in other sections, I wish you the best, and I believe in you :) If you're reading this and you have other options for professors, please please please take them instead.
Dmitry Dolgopyat DATA400 Expecting a B- Anonymous 11/08/2023	He can't teach for the life of anyone. His sample problems, solutions, and everything else he has ever laid his hands upon are unreliable. Better to drop the course than have this teacher. Run far away. Not worth it. Will screw up your GPA. Doesn't curve.
Mestiyage Gunatilleka DATA400 Expecting an A+ Anonymous 07/26/2023	Great professor

Jonathan Fernandes
DATA400

Expecting an A
Anonymous
05/30/2025

If you do the work, you should be able to get an A. I initially struggled, but once I found the rhythm of the course, it became much easier. He provides sample questions for the exams - which are based of homework and the examples he covers in class. While he will not provide a solution manual for these problems, if you keep up with the work, it is not hard to find the answers in his notes. Also his exams are not the practice exam with numbers changed, so be careful about that. He expects you to work through all of the content covered in lectures! I did not find the final exam particularly hard, as most of it was based off what was done in lectures and discussion ... but this could just be me. I did study a lot for it though. All in all, I found this to be a useful class, and if you have the chance you should take it with Fernandes. You might have to work some, but you will learn a lot!

Jonathan Fernandes
DATA400

Expecting an A
Anonymous
05/21/2025

On the whole I would recommend this class. It is a hard class, and he expects you to work on the content. People say Stat400 is an easy A, but it was not the case for me. I did have to put a lot of effort, and the class is generally well supported - with him going over concepts and examples during lecture, and TAs working on homework problems. Somehow he has really cool TAs who go out of their way to help you! He has in-person quizzes during discussion - which I did not particularly like, but he allowed for students to take make-ups within a week if they missed any. Just because of this I would take one star off, but then the 1-star review below me (from 05/20/2025) is flat out lying to the point that I am wondering if this person was somehow going to a different lecture all all semester long - so will give 5 stars!

Jonathan Fernandes
DATA400

Expecting an A
Anonymous
05/21/2025

As someone who struggles with math and statistics, this course truly helped me appreciate both the mathematical background and the practical intuition for many of the concepts that were thought ... while I found most of his lectures very engaging, I particularly liked the way he explained bayes theorem. The lecture on covariance and linear relationship was fun too ... if you connect with his style and humor, the lectures are pretty nice and worth going to. His exams, especially the final is admittedly hard ... but he covers all the content and solves many of the problems during lecture and discussion (he has some of the most amazing TAs!!!). If you go to lectures and redo the examples from there, and the discussion, you should have no problem with the exams. Also, he adjusts the grades at the end of the semester and allowed for one homework resubmission, so as long as you are consistent with your work, you will be good! He also records all his lectures, and live streams his notes ... which was very helpful for me.

Sana Jahedi
DATA400

Expecting a B+
Anonymous
05/08/2025

Never in my college experience have I come across a group of people who don't know that they don't know, take no responsibility, and then shit talk the instructor like they know better how to teach the class. If you ever want to know experimental evidence of the Dunning Kruger Effect, take Stat400. Of course, Prof. Jahedi has their shortcomings like any other human would, however, trying to blame and cyber bully her over here when you could talk to her in person and get the feedback you need, even if it means you need to work on your study habits (mind you, the semester is yet to be over!) is the very reason why the educational system in the US is focussed on customer service than actual learning!

Sana Jahedi
DATA400

Expecting a B
Anonymous
05/06/2025

The reviews here are the reason why we don't deserve good things - downright cyber bullying!!! She is not that bad, and does genuinely put effort in her teaching. While the class is hard, many will come in expecting to get an A with minimal effort sometimes taking with over 15credits of coursework. It is not an easy class! Using PlanetTerp to harass an instructor, only decreases the credibility of this website! I sometimes worry about the dumbass impression about UMD students that these reviews convey to those outside of UMD (some reviews here downright complaining that this was not an easy A they hoped for, lol) , and god forbid my prospective job interviewers.

Sana Jahedi
DATA400

Expecting an A+
Anonymous
05/05/2025

took sana's data400/stat400 class in fall 2024. it was probably my class' fault that the class is so bad now; people would constantly abuse the extremely generous grading and retake system to the point she had to take it away (including straight up leaving after putting their name down during group quizzes), people would gossip and talk in class at regular talking volumes while paying zero attention to sana to the point where she got fed up and sometimes asked students themselves to come up and explain topics for extra credit, and people would openly brag about how they didn't know the content and just memorized the practice exams WHILE IN CLASS/IN FRONT OF HER to the point where she just gave up and put the easiest problems from the problem pool on the final. all of that might be completely justified: why not get the most out of the retake system before its gone? if the lecture wasn't helping you, why not just ask a friend what was going on during class? if the best way to get an A was to memorize, why not just do that? but i think people went about it in such a disrespectful way that fall 2024 was genuinely an awful experience for sana very early on in her lecturing career and probably the reason she is so spiteful/'mean' this semester.

Sana Jahedi
DATA400

Expecting a D+
Anonymous
05/04/2025

I took STAT400 with Sana Jahedi, assuming it would be fair based on PlanetTerp. I was so wrong - despite Sana's smug lecture on how everything is "fair" and it was "all our fault." Let’s start with the facts: Sana is clearly knowledgeable (I'd hope considering she has had a lot of education), but she teaches like she’s trying to keep the secrets of probability secret. Her lectures often feel like you're walking into the middle of a conversation that started without you — and also maybe in another language. Concepts that could be explained with a simple example are instead buried under abstract generalizations and chalk dust. Office hours? Yes, they exist. Will they help? Debatable. Exam prep? There are no practice materials, and the exams themselves love throwing in curveballs and notation you've never seen before — like a pop quiz on a different course. Honestly, I’m just glad Sana’s PlanetTerp rating is now just as low as her exam averages. Balance has been restored to the statistical universe.

Sana Jahedi
DATA400

Expecting an A-
Anonymous
05/04/2025

his class has been a mental marathon with no water stations. Sana’s lectures feel more like TED Talks than actual lessons—lots of abstract musings and philosophical tangents, but very little in the way of concrete, step-by-step instruction. The notes are a cryptic mix of bullet points and vague definitions, and we’re expected to reverse-engineer the logic behind them on our own. She says the exams are “straightforward” but then throws curveballs that feel like grad-level trick questions. You know it’s bad when the homework feels hard and the exams feel worse. And don’t bother asking for clarification—she rarely entertains follow-ups, and when she does, the answer usually makes things more confusing. There’s no review session, no sample questions, no guidance. If you do poorly, the response is always, “Well, I thought it was fair.” There’s no acknowledgement of any disconnect, just this unshakable insistence that we’re all just not trying hard enough. Honestly, I’ve never felt more gaslit by a class.

Sana Jahedi
DATA400

Expecting a C-
Anonymous
05/03/2025

Her lecture problems, quizzes, and homework vary in difficulty, but the exams are significantly harder than any other assessment. The material covered in lectures does not align well with the content or difficulty of the exams or any other graded assignments, making it extremely difficult to prepare. She does not provide practice problems for the midterms, and despite low exam scores, she takes no accountability—refusing to offer a curve and instead placing the blame on students. This class has had a severe negative impact on my GPA. I regret not choosing a different professor, as her final semester of teaching felt intentionally harsh.

Sana Jahedi
DATA400

Expecting a B+
Anonymous
05/02/2025

Hi Sana. I know you read these. So let me just say: respectfully, this class is statistical warfare. Every time you said “This one’s not too bad,” I knew pain was coming. You’d write 4 lines of gibberish on the board like that meant anything to anyone in the room. It wasn’t obvious. I did every homework. I went to every lecture. I still felt like I was guessing on the exams like it was a personality quiz: Please consider updating your exams so they resemble what you actually teach. Or at least warn us that the exam would actually be the end of us. Anyway, keep a look out for my therapy bill in the mail. Sincerely, A Survivor.

Sana Jahedi
DATA400

Expecting a B
Anonymous
05/02/2025

The quizzes lull you into a false sense of security. Then the exams come in like a jump scare. Stat400 with Jahedi is a rite of passage. Like parallel parking or assembling a fan from Amazon — painful, but you grow from it.

Sana Jahedi
DATA400

Expecting an F
Anonymous
05/02/2025

I really wanted to enjoy STAT 400 after reading great reviews of Professor Sana, but this class has been a struggle. In lecture she often speaks without a microphone, and I find myself straining to hear the key ideas. Instead of walking us through examples, she’ll share personal stories or life advice—great in small doses, but it leaves us scrambling when it’s time to learn the material. When she does dive into statistics, it’s at lightning speed. I’ve lost track of how many times I’ve raised my hand only to see the lecture move on without checking if we understood. Early on she promised that a strong Quiz 2 score would replace our Quiz 1 grade, but that rule was quietly withdrawn later in the term. That kind of last-minute change really shook my confidence. I also wish we had more concrete practice. There’s no sample midterm or review sheet, so it’s tough to judge pacing or question style when the actual exam time arrives. Some homework questions feel vague or unlike anything we covered in class, and when I post on Piazza, I get the participation credit—but the real answers often don’t come until much later, if at all. I know every instructor has a different style, and I appreciate that Professor Sana wants to connect on a personal level. But for me, the balance has tipped too far away from clear, step-by-step teaching. If you learn best with guided examples, regular check-ins on understanding, and plenty of practice materials, you might find this section of STAT 400 frustrating.

Sana Jahedi
DATA400

Expecting a B-
Anonymous
05/02/2025

For the Spring semester, Sana decided to change up how she ran STAT400 class. Do not trust the reviews from before Spring 2025 because the class has fundamentally changed. The gap in difficulty between different parts of this course is jarring. The content in the homeworks and discussions are sometimes out of the lecture's scope, yet Sana expects her students to be able to extrapolate concepts from the lecture and apply them to harder questions (questions that we've never seen before). She's expecting her students to solve problems on her exams (problems that also barely show up in lectures/discussions/homeworks) as she intended and with a specific line of intuition. Unfortunately, most students taking this class don't have that kind of intuition, and at the very least, there should have been more practice problems and explanation. Instead, the two exams we've taken so far feel far more difficult than the quizzes we get. I don't recommend taking this professor, especially if you need to fulfill your major requirements. The professor asks alot for people who aren't aspiring staticians.

Sana Jahedi
DATA400

Expecting a B
Anonymous
04/29/2025

Just horrible. Last semester she great according to reviews due to her very student friendly polices. Yeah none of those exist anymore. She essentially gives 0 study material. You're supposed to use your discussion worksheets and homework as your study material. She is rude, mean and condescending. She acts like students are just there to waste her time. This past exam was possibly the worst exam I have taken at UMD and I would not be shocked if the average is sub 60. In class she essentially blamed all of us for not studying enough and said that it was our fault. So if you take her you are dealing with someone that has 0 accountability. Her lectures are completely a mess and make 0 sense most of the time. I guess she has decent slides that will kinda help you understand the material, but that does not help you at all on the exams. Do not be fooled by past reviews, take anybody else! I could keep going on and on but I think you get the point. Save your GPA and take anybody else

Sana Jahedi
DATA400

Expecting a D+
Anonymous
04/25/2025

I genuinely didn’t know a person could be this bad at teaching and still be employed. Her lectures are incoherent, her attitude is trash, and her exams are rage-inducing. The only consistent thing about this class was the suffering.

Sana Jahedi
DATA400

Expecting a D+
Anonymous
04/25/2025

If I could rate her zero stars, I would. Actually, negative stars. This class takes away knowledge. I came in knowing some things, and now I know less. A void has opened where my brain used to be. Thanks, Sana.

Sana Jahedi
DATA400

Expecting a D
Anonymous
04/25/2025

This class made me reconsider my entire major, my career path, and whether humanity deserves education. I walked in optimistic. I walked out emotionally bankrupt. She doesn’t teach — she torments. Save yourself.

Sana Jahedi
DATA400

Expecting a B
Anonymous
04/25/2025

Nothing prepares you for this class — not the lectures, not the practice problems, not even divine intervention. She gives you study material, then tests you on something completely different and acts like you should’ve known better.

Sana Jahedi
DATA400

Expecting an A-
Anonymous
04/25/2025

This professor is a disgrace to education. I have never encountered someone so unqualified, unhelpful, and outright cruel in a position of power. The midterms were a complete joke — not even remotely related to the practice problems or lectures. It’s like she went out of her way to make the test as confusing and convoluted as possible, just to flex her ego while watching students fail. She does not care. Not about teaching, not about students, not about anything but hearing herself talk. Every interaction feels like you're being talked down to by someone who thinks empathy is a weakness. Asking questions? You're treated like an idiot. Asking for clarity? You're met with attitude and passive aggression. This isn’t just a bad class — it’s emotional whiplash. She’s condescending, detached, and deeply unpleasant. I genuinely believe she gets satisfaction from watching students suffer. This was not just frustrating — it was demoralizing. Her attitude is toxic, and her incompetence is astounding. If you value your time, sanity, or basic dignity, do not take this class. I wouldn’t wish this experience on my worst enemy.

Sana Jahedi
DATA400

Expecting a C-
Anonymous
04/25/2025

I don’t even know where to begin because this class was an absolute nightmare. The midterms were completely disconnected from the practice problems — as in, studying felt like a waste of time because nothing prepared you for the sheer randomness and cruelty of the exams. It honestly felt like she enjoyed watching students struggle. And don’t expect an ounce of understanding or humanity. This professor is cold, condescending, and completely checked out. She doesn’t care if you’re confused, doesn’t care if the whole class is struggling — she just keeps going like it’s your fault for not being able to read her mind. I’ve never felt so disrespected or demoralized in an academic setting. She has no business teaching, let alone interacting with students. It’s not just bad teaching — it’s actively harmful. This class drained my motivation and made me question why I even try. If I could give negative stars, I would. Run.

Sana Jahedi
DATA400

Expecting a C
Anonymous
04/25/2025

This professor is hands down one of the worst teaching experiences I’ve ever had. The midterms were completely disconnected from the practice material, almost like they were designed to trip you up rather than test your understanding. It’s infuriating to prepare based on what we’re told to study, only to be blindsided by questions that feel intentionally misleading or cruel. What makes it worse is the complete lack of empathy or support. Asking for help or clarification feels like an inconvenience to her. It’s honestly shocking how little regard she has for her students — academically and personally. She’s not just a bad teacher, she’s a deeply unpleasant human being to deal with. I wouldn’t wish this class on anyone. Avoid it if you value your GPA or your sanity.

Sana Jahedi
DATA400

Expecting a B
Anonymous
04/24/2025

can't teach. hws are harder. quizzes are not in groups anymore. does not provide a review guide for exams anymore bc students did too well -> exams are harder literally looked at her reviews and and said fuck u guys and made the class harder than it needs to be. generational fall off.

Sana Jahedi
DATA400

Expecting an A
Anonymous
12/30/2024

Highly incompetent and cannot speak English. She tries to cover her incompetence by being "sweet". Guess what? we are here to learn from someone who knows what they are doing. We do not come to have a "sweet" instructor who struggles in English and struggles in the material at hand.

Sana Jahedi
DATA400

Expecting an A
Anonymous
12/21/2024

She has no clue about data or stats. Not sure who gave her this course. folks go learn with someone else.

Sana Jahedi
DATA400

Expecting an A
Anonymous
12/16/2024

Sana is a very fair professor. Things to note: - Discussion had mostly group quizzes - When we don't have quizzes, there are ungraded worksheets, a great way to practice and ask questions from TAs if you need help. - Every discussion problem and homeworks have detailed solution that Sana spend time to provide. - We had only about 6 quizzes and 7 HW. - Everything thing that is graded or provided is fair and on level. (Homeworks and Exams). - Lectures are easy to follow. For those with ipads, she posts pre filled notes so taking notes are easier.

Jenna Zomback
DATA400

Expecting an A
Anonymous
12/14/2024

Zomback is the best math teacher I’ve ever had.

Sana Jahedi
DATA400

Expecting an A
Anonymous
12/14/2024

Shes very understanding and as long as u do the study guide youll do just fine on exams highly recommend her

Sana Jahedi
DATA400

Expecting an A-
Anonymous
12/11/2024

Her teaching in lecture wasn't my favorite, but she is very generous grader and offers very easy extra credit if you need it. She posts good notes and is great at explaining things in office hours. She also is very understanding and flexible if you ask her about anything.

Sana Jahedi
DATA400

Expecting an A+
Anonymous
12/11/2024

Midterms went over EXACTLY what we learned in class, review practice problems, and discussion (also gives ANSWERS!! to all of them as well, so just remember how to do those and then you're good for the midterms). Posts notes after class and has a piazza for questions (she answers pretty quickly imo)

Sana Jahedi
DATA400

Expecting an A+
Anonymous
12/08/2024

Very understanding teacher, exams are just like the study guide. An A is basically guaranteed as long as you go to class.

Sana Jahedi
DATA400

Expecting an A-
Anonymous
12/05/2024

exams exactly like practice tests not too hard. Very easy grader and super nice teacher.

Sana Jahedi
DATA400

Expecting an A+
Anonymous
11/15/2024

She is one of the nicest professors and understands you. Offers help, her exams are just like the practice so if you get the hang of that you should be fine. She is also very sweet. quizzes and labs (which are like group quizzes) every week, you have about 7 of these a semester are super fair but attendance is mandatory in disscussions. 2 midterm exams 15% of your grade each. definately recommend her for stat 400.

Sana Jahedi
DATA400

Expecting an A+
Anonymous
11/12/2024

She is one of the best stat teachers. She is super lenient, lectures well, gives fair quizzes, and there are a lot of team quizzes. 10/10 would recommend if you need to take this class.

Sana Jahedi
DATA400

Expecting an A+
Anonymous
10/26/2024

Definitely one of the nicest professors I've ever had, especially if you meet her in office hours. She teaches the material really well, down to earth and always willing to follow on with you or meet you privately if you need help. Her exams are mostly easy and her work doesn't destroy you mentally because she gets that you have other classes and whatnot. Would definitely take her for this class.

Sana Jahedi
DATA400

Expecting an A
Anonymous
10/22/2024

She is the goat. Her practice exams is exactly like the exam. She's understanding and nice. Best prof I've had in MATH department, heavily recommend.

Sana Jahedi
DATA400

Anonymous
09/27/2024

really good thumbs up emoji (I'm not writing a paragraph)

Fushuai Jiang
DATA400

Expecting a C-
Anonymous
07/16/2024

Do not take his class trust me. If this review saves one person it was worth it.

Jonathan Fernandes
DATA400

Expecting an A
Anonymous
05/21/2024

He is very nice and generous, but his curriculum and notes could be structured better.

Fushuai Jiang
DATA400

Expecting an A+
Anonymous
05/16/2024

Dr. Jiang is not a good professor. He doesn't communicate with the TAs, all of his lecture content is directly out of the textbook (and he uses his own preferred textbook instead of the STAT400 standard book), and he answers questions in a usually confusing and occasionally condescending way. He's a nice guy and will help in office hours if you go, but he intentionally teaches this class at a very high difficulty compared to the other STAT400 teachers. Average on the first exam was ~55%. If you don't know a lot about proofs you will definitely struggle in the first half of the class, but even if you know proofs well its still very difficult. Exams are weighted: 20%, 20%, 40%, so pretty much they are the only important grades. This class would only get one star if not for the absolutely massive curve. Most people did really poorly on the exams so the curve was huge, so you might end up with a passing grade even though you didn't do well on the exam. Be prepared to put in a ton of time studying outside of class if you want to understand the content and do well on exams.

Jonathan Fernandes
DATA400

Expecting an A
Anonymous
05/01/2024

The class is so free– he gives 90% of the test material in the study guides for the test. Has a tendency to overexplain. Homeworks are challenging but help to prepare you for the test. Quizzes are bullshit but they're online and you have multiple attempts. Also, this guy does not respond to emails

Fushuai Jiang
DATA400

Anonymous
03/03/2024

He writes notes, not that legibly, in notability, and fails to really explain any proof, and instead writes it word for word from the text book. There were times when people had questions, and he stated that "it was outside the scope of the course". His review problems for the test are not close at all to actual problems present on the test and instead are random proofs and questions he's taken over all his lecture. TA's are nice and are the only way to get through the course, but most of the time they have no idea what he's doing. You are allowed a cheat sheet on exams, but it only helps if you happened to copy the right proof down, or else good luck figuring it out intellectually on exams when you likely won't. Overall, take any other professor for STAT400, because they are all way better in terms of grade distribution and teaching ability. If you were forced to take Professor Jiang, then I wish you the best of luck, you'll need it.

Dmitry Dolgopyat
DATA400

Expecting an A
Anonymous
12/25/2023

Lectures are very difficult to understand, focuses too much on the underlying theory leaving you really confused on what he's trying to explain. 9 times out of 10, after self studying I realize that the content is actually not that hard, he's just not very good at explaining. Most people skip the lectures and do fine. His tests, quizzes, and homework are actually pretty reasonable and he is pretty generous about how they are graded. You can pass this class if you work hard, but I can definitely say there's easier professors to take.

Dmitry Dolgopyat
DATA400

Expecting a B-
Anonymous
12/19/2023

Clearly a very smart person and knows a lot about the subject. However, he is not meant to be a professor. I was lost in all of his lectures. Office hours were very difficult to figure out. His answer keys for reviews had a lot of errors and were hard to follow and understand. Not sure I really learned anything from this class. The fact that quizzes (30%) are worth more than exams (20%) is what got me a B-.

Jonathan Fernandes
DATA400

Expecting a B+
Anonymous
12/18/2023

The first half of the semester really deceived me. Homework was doable, and the first exam was genuinely copy and paste the sample exam, even though we did not have access to a calculator. But then things suddenly shifted once the second exam came around. For the first exam, he went over the entire sample exam in class and discussion, for the second one, he only went over a few in class and the rest were just in the air. Mind you, these questions are a lot harder and it's tough to conceptualize without seeing an example of it. I had to go on a scavenger hunt to find answers, some were in lecture notes and others were found in homework answers. I even had to scan through answers from PREVIOUS YEARS to find close answers. The worst part is the second exam was not simply a copy and paste from the sample. Now here comes finals, he posts a sample exam with 36 QUESTIONS!!! and does the same thing he did for the second exam. He expects us to find answers & examples through his lecture notes and homework and all over. Overall a very frustrating exam experience. Knowing that his exams are derived from his samples (he even tells us this), it is all the more important to have some sort of answer sheet explaining some of these questions. The questions are typically one of a kind and were only mentioned once or twice on homework or lecture so often times students don't have a full grasp on how to apply their knowledge to such problems. He is overrated simply because he curves, but do not expect this class to be easy (don't let people fool you like they fooled me) TAKE MESTIYAGE, HE ALLOWS A CHEAT SHEET AND CALCULATOR!!!

Dmitry Dolgopyat
DATA400

Expecting an A
Anonymous
12/15/2023

I cannot say enough positive things about Mr. Dolgopyat. From the moment I stepped into the classroom, I knew I was in for an amazing semester. His passion for statistics was infectious and made me excited to learn. One thing that sets this teacher apart is their ability to make complex concepts easy to understand. They have a way of breaking down difficult material into manageable pieces, and their explanations are always clear and concise. His use of real-world examples and hands-on activities made the course material come to life and solidified my understanding of the subject.

Dmitry Dolgopyat
DATA400

Expecting a C-
Anonymous
11/22/2023

I just want to make something very clear first: Dmitry is clearly a brilliant man and knows what he's talking about... He's just not a very good lecturer. If you're going to take this class, I hope to you're comfortable with reading chapters out of a textbook to teach yourself, because that's all your semester will consist of. I stopped going to his lectures because I realized that teaching myself the material from the textbook was genuinely a more productive use of my time. Dmitry's midterm study material (practice exams) are a 50/50 when it comes to how similar they are to the actual exams (first midterm -- actual exam was easier than practice; second midterm -- actual exam was on par with practice in my opinion), so it's stressful to try and figure out whether it's over for you or not, while doing the practice exams. I'm the type of person to find the positive in every terrible situation, so I'll try to do the same here. You get weekly homework assigned to you on Webassign, and honestly, I'm always able to knock those out within around 1.5 to 2 hours, and the problems are straightforward enough such that you're able to read the textbook and (mostly) know what to do. Not only that, if you genuinely and honestly do well on the homework assignments, the weekly quizzes are easy, since they're pulled straight from the homework (albeit with different numbers). Yeah, that's it... Whoever you are reading this, if you're like me and took this class due to lack of openings in other sections, I wish you the best, and I believe in you :) If you're reading this and you have other options for professors, please please please take them instead.

Dmitry Dolgopyat
DATA400

Expecting a B-
Anonymous
11/08/2023

He can't teach for the life of anyone. His sample problems, solutions, and everything else he has ever laid his hands upon are unreliable. Better to drop the course than have this teacher. Run far away. Not worth it. Will screw up your GPA. Doesn't curve.

Mestiyage Gunatilleka
DATA400

Expecting an A+
Anonymous
07/26/2023

Great professor

Reviews for DATA400