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Opiniones y comentarios de aprendices correspondientes a Data Wrangling, Analysis and AB Testing with SQL por parte de Universidad de California, Davis

502 calificaciones
185 reseña

Acerca del Curso

This course allows you to apply the SQL skills taught in “SQL for Data Science” to four increasingly complex and authentic data science inquiry case studies. We'll learn how to convert timestamps of all types to common formats and perform date/time calculations. We'll select and perform the optimal JOIN for a data science inquiry and clean data within an analysis dataset by deduping, running quality checks, backfilling, and handling nulls. We'll learn how to segment and analyze data per segment using windowing functions and use case statements to execute conditional logic to address a data science inquiry. We'll also describe how to convert a query into a scheduled job and how to insert data into a date partition. Finally, given a predictive analysis need, we'll engineer a feature from raw data using the tools and skills we've built over the course. The real-world application of these skills will give you the framework for performing the analysis of an AB test....

Principales reseñas

22 de sep. de 2020

A good course for learning and apply sql to conduct analysis on ab testing results. Would be better if the instructor could provide more info about how to design and apply AB Testing on the customers

29 de jul. de 2019

The instructor is very smart and her syllabus is very easy to follow. The real life examples are great and helps put ideas in perspective! I would definitely recommend this course and already have!

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126 - 150 de 188 revisiones para Data Wrangling, Analysis and AB Testing with SQL

por Jill z

9 de sep. de 2021

I don't think it's a good course.

To be honest, the content is very good. However the relation of different datasets is very very very ambiguous , it's difficult to finish the case study.

por PT R

23 de jun. de 2020

The practice examples are not written well- it is hard to understand what is actually being asked. This was also true for the final peer-reviewed example.

por Ben

23 de ago. de 2020

The content is good, i appreciate that linking SQL with some data science subject such as AB test. that's the main reason for me taking this course.

por QianHe

12 de jun. de 2020

It seemed a bit disjointed. The instructor seemed nervous. Some of the solutions to the exercises seemed overly complicated.

por Iván A A

28 de jun. de 2020

The project's instructions are not clear.

por Azka A

10 de may. de 2020

The lectures could be more detailed.

por Sachin G

15 de jun. de 2020

No good course

por Lea P

2 de may. de 2021

I definitely learned a lot during this course. I gave a 2 star rating because there are a number of issues/loss of time while taking this course

1 Practice sessions:

- Questions are often unclear, not guiding you to what you actually need to get to.

- Answers as given as a video. It's good to get a couple explanation about some steps, but often the code shown is incorrect, and the teacher spends minutes trying to correct it. Also, THE ANSWER SCRIPT IS NOT GIVEN. So you have to waste your time copying every line to test out their script! Very inefficient

- You have to add a comment to the practice exercise to move on to the next step. All these responses (thousands of them, random word/comment to move on) will show up in the forum discussion when you try to find an answer to some of your questions . The coursera search engine is pretty inefficient. So combined with these tens of thousands of unuseful comments, it's impossible to find the answer to any question.

- I looks like the instructors are not very active. I encountered a lot of posts in the forum that had no answers. And given the low number of people currently doing this course, it's unlikely that you'll get an answer to your posts.

2. Final assignment:

- Low traffic on course: There's no peer assignment to review. And no one to review yours.

- Exam questions are often unclear. So the least would be to clearly state what you'll be graded on, rather than finding this out when you submit your assignment

- Often refers to a script made sometime during the course. Very hard to find which script they are actually talking about, so you have to go on a scavenger hunt every time. That's also the case in practice questions

Kat, thanks for the course. I'm sure you put a lot of efforts in creating this course and content, but in order to turn this into a great course, you need to have people test it and use the feedback to improve it.

It's a shame that the instructors to this course will probably never read these comments, so this course will stay as a draft course forever. I don't know much about UC Davis, but with a course like this, I'm unlikely to recommend a UC Davis Course or a UC Davis degree to anyone.

por Rita N

24 de ago. de 2020

This course is not nearly as good (or even "good") as the first course of this specialization. Concepts are taught too vaguely and the material is scattered in an order which doesn't make sense. It would have been helpful to know from the _beginning_ the tricks for coding in Mode, such as selecting multiple lines to comment out...instead, those tips were placed in the middle of the entire course as an aside. I wasted so much time looking up how to multi-line comment-out (couldn't find an answer) and ended up doing it the long way until that point of the course...when she could have mentioned it _from the very beginning_!

The idea of do-it-yourself exercises and answers-video was nice, but the instructor was not helpful during these videos. She mumbled a lot through her actions, so it was like a puzzle trying to figure out the rationale and intention behind her decisions. Lots of vague language...I get that sometimes things can be vague because this course can't cover every scenario, but I could find better explanations elsewhere online.

I spent more time looking up outside resources for things like pivot tables and windowing functions (not taught in the previous course) than learning it on Coursera. I'm left feeling like I spent money to teach myself these things, and could have saved the money I spent on this course.

All-in-all, I couldn't finish the course. I spent about 16 hours trying to perform the 5 steps to complete the final project for A/B testing the given dataset, and I wasn't even able to recreate the table she wanted to start the thing off.

This feels so bad. I hardly ever give up on something, but because there's no instructor feedback and almost no feedback from other students, there's just no way I can get through this. What a disappointing experience.

por Derek E

9 de mar. de 2021

Most of the negative reviews for this course are accurate in my opinion. After reading the reviews, I decided to give the course a try anyway and I'm pretty disappointed that I invested as mush time in it as I did. The hands on exercises from the first week were beneficial and helped reinforce the learning from the first course in the specialization. Beyond that, I would say that the course seemed to lack an effective plan aimed at developing students SQL skills. It was apparent that the instructor is both knowledgeable and competent in SQL, however that knowledge and competency didn't translate into the ability to transfer knowledge to others via the course content.

I would of liked to have seen the presentations structured like those from the first course of the specialization. It would have been beneficial to have ER diagrams for the databases used in the hands on exercises. I can't say that the coding videos were much help, as there was little to no explanation as to what the instructor was doing and found myself struggling to stay awake while watching them. By the third week of the course, it seemed apparent that the specialization lacked an overall plan and the courses were created on an individual basis, rather than by a team working together to execute a well thought-out learning plan.

I wish I could give this course a better rating, but beyond the hands-on exercises from the first week, I wouldn't recommend the time investment to anyone, even those interested in pursuing the specialization.

por Daniel J

23 de sep. de 2020

While I appreciate the numerous practice exercises in this course, the experience overall was incredibly frustrating.

On the one hand, it's hard to check my practice queries against the instructor's recommendations when the solutions videos contain so many mistakes and so much typing. The instructions themselves were often confusing, and I wouldn't realize until watching the video that I had completely misunderstood large portions of the assignment. Because each query builds on the previous one, this meant going back and redoing the entire exercise.

On the other hand, I found several mistakes in the quizzes and support materials. It was easy enough to figure out what the answer was supposed to be, but this was still annoying for a paid course.

Most frustrating of all was the final project, however. The assignment itself was good, but having to submit it as a Mode report was incredibly confusing--it wasn't at all clear how I was supposed to show my work, and it would have been much easier to submit a text file with my code instead. After all, the peer reviewing students have access to the same databases and can quickly run my code to make sure it checks out.

Perhaps I'm being a bit harsh, since I've taught data cleaning for Stata and therefore probably have higher standards than most students. But I can only imagine how lost most students are in this course, since it's only the second level in the SQL certificate, and I imagine most do not have a technical/coding background.

por Alexander P

15 de abr. de 2021

Kat is a charming teacher. I think she really has a passion for it and that comes across. But the course itself is extremely poorly structured. I found myself not caring about the data (oh no!) very quickly in. I think in an effort to teach how vague questions about data can be (a good lesson...) the course became very vague and scattered itself.

Exercises are unclear and I found myself unable to complete them or even know what was being asked. The online applet through Mode worked OK, but was frustrating to learn and with no ER diagram for the databases we were supposed to use, it was a bit overwhelming. The minute you start typing, it comes up with suggestions for a million connected databases or functions, and you don't know what belongs to the course and what is default etc etc. It's a very frustrating experience.

The PDFs for the coursework are underdefined, they don't always reflect the state of the database as you find it, and the solutions videos themselves are badly edited - there was one video where I sat through minutes of Kat solving a bug on her computer trying to get a graph displayed (nothing to do with the course!) before she gave up, ended the video, and moved us on to part two, where it picked up after she'd fixed the bug.

Course needs to be much tighter to be useful.

por Brent S

21 de jun. de 2021

This course has a lot of important things to teach and mostly accomplishes those goals. However, the structure of the course leaves much to be desired, it expects you to know SQL skills that weren't taught in the first course of the series, and, most importantly, doesn't respect your time. For instance, the course has you reference code from screenshots for problems rather than text of the code (you can't copy and paste from a screenshot). Additionally, the final test expects for you to reference code from the lectures or already have advanced SQL knowledge so I ended up having to rapidly resume/pause the videos while the lecturer was scrolling just to get the starter code to work with (it also didn't tell you what table to reference for the test scenario).

Kat seems like an incredibly intelligent and kind person that would be great to learn from outside of this course as she has a wealth of knowledge, but there are just some basic fundamentals to a course's structure that this lacks that make this course much harder than it really needed to be. I learned a lot about what you can do with SQL and am better off for it, but there are just some basic things that can be done from a quality assurance standpoint that NEED to be done before this course is recommendable.

por Alexander H H

26 de may. de 2021

This course was an absolute mess. I am not sure that I learned a single useful thing throughout the time that I spent on it. The quizzes usually included questions that were poorly worded in a way that prompted incorrect responses. Even when that wasn't a problem, questions that asked which video covered a specific question occurred. These questions are lazy, unhelpful, and a terrible way to try to teach understanding of a concept. The videos were also not great, and frequently barely skimmed the surface of concepts that seem important. Even the final project included at least one problem that was worded in a way that made absolutely no sense, and seemingly asked for impossible to produce code. An unintended concept that I did learn while taking this class is to use Google to help you imporve your code, because 5 minutes on Google was more helpful than an hour of trying to decipher this nonsense.

If you need this class for the SQL for Data Science specialization, just try to get through it. If you actually hope to learn anything, skip this course. You can teach yourself everything it covers considerably better than they do.

por Moritz P

23 de ene. de 2021

I just want to take the time again to critique this course. I found the first in the series (SQL for Data Science) way better than this one. Make no mistake, it was really insightful and helpful. However, the practice of forcing people to comment before being able to watch the next videos just leads to a lot of non-sense in the discussion forums, disturbing all others who really want to discuss. Additionally, this course was way less engaging than the first one and made considerably less fun practicing. Especially, when tasks in the PDF are only described in broken sentences and when in the actual solution videos SQL code is copy-pasted so quickly that there is no way to catch-up. Yes, one could pause. However, this really disturbs a progressive learning atmosphere and destroys the joy of coding, at least for me.

por Maor L

15 de mar. de 2021

Good Riddance! On the positive side, the course covered very important aspects of SQL and forced me to learn by myself several methods in SQL. However, the course structure was very bad, and I won't be surprised if many students have left the specialization at this point, not because of its difficulty, but because of the contents. Here are some of the main problems of this course - the instructor isn't correlated with the presentations, the Mode tasks are poorly drafted and there isn't a clear guide how to use this platform (which is essential to the final project), many questions in the tests are very ambiguous. Basically I would recommend US Davis to restructure this course in a way which will be in the same high level of the first course by Sadie, and in a way it won't be so frustrating to learn it.

por Tim S

20 de jun. de 2020

The use of mode made the experience for this course a bit clunky; also the final assignment could have been outlined more in line with the rubric. A model to emulate is the use of SQL lite in the first course. To add I was hoping that there would be a way to programmatically determine A/B testing vs. using an external tool; perhaps the third week assignment would be to code up a SQL significance calculator then in the forth week use that model to the data. These are the reasons why I give this course 2 stars. This of course might be very difficult given that SQL is not a functional language (I personally haven't tried this). The instruction, exercises and the design really make me stop and learn key concepts and the professor's recorded demos were excellent.

por Rifqi R

24 de nov. de 2020

honestly, this course feels like navigating through a foreign city without any knowledge of the landmark.

class is confusing. more query statements introduced without any proper introduction to the query made this class is lacking sense of continuation from the previous ones.

the training/examples are not streamlined with Coursera's built in quiz feature. using app.mode is a new thing and the intro to the app isn't well explained.

training instructions are confusing and the solutions aren't helping, for example, we need to find what's wrong in a query, while we're confused and trying to find the solutions in the solutions videos, why not throw in graphs into the mix and make us more confused..

por Daniel O

16 de may. de 2021

This was the second course in the Learn SQL Basics for Data Science. It felt like big steps were skipped in between. What was even more frustrating was that the instructor said multiple times that material should have been covered in previous courses and/or to search Google if the learner was unfamiliar with any topic. I’m certain some areas were not covered and telling students to search Google is just lazy. I also felt that the instructor did an excellent job of showing her knowledge on the material but failed to properly explain what she was doing or why.

por Jacob R

10 de oct. de 2021

T​his was good SQL practice but overall the course quality was poor. Instructions were at times unclear and unpractical (e.g. expecting students type dozens of lines of starter code instead of letting them copy-paste them). The video lectures were useless as they tended to be more about data science as a whole. Kat Glaeser is simply a poor instructor, with many glaring editing and speech mistakes in her lectures. I'm disappointed I paid for this course while there are hundreds of higher quality and free exercises and videos elsewhere on the internet.

por José M V D

3 de mar. de 2021

This was a very disjointed course and unfortunately the worst Coursera course that I have made so far.

The teacher was good, it seems that she knows a lot about the SQL concepts explained in the course, but I don't think the concepts are well explained. You can learn something from the exercises, but only once you see the solution. Before seeing the solution, it is often hard to understand what you have to do.

To sum up, I would not pay again for this course, and I would not have finished it, if it wasn't needed to get the certification.

por Luke F

12 de jun. de 2020

The lecturer is clearly friendly and passionate. However, as other reviewers have noted, this course introduces more complex areas of SQL with no explanation. The videos before the assignments provide little insight into how to do them afterwards and instead I found myself skipping them and then just watching cluelessly as the solutions were quickly banged out. I appreciate the efforts of the instructor but I feel this course needs to be a) refined and b) simplified for those of us coming off the first data science course.

por Ka W S

9 de abr. de 2021

If you come from the last course of this series, i would say stop this course. They expect you to know many things you didn't learn in the first course, and the teaching style is not helpful. I will not continue this certificate due to the quality of this course. Some of the answer they give out are wrong and the explanation is not good. I will change to a different certificate. I wonder why this course has so many bad reviews, so I know it.

por Annamaria N R L S

29 de may. de 2020

Interesting Course. had more opportunities to practice, but would recommend that the incoming student have more practice and experience before starting. Still rather disorganized and some parts (i.e. explinations and subject videos0 in need of review by creator (i.e. gaps in explanations, vague directions and instruction, etc.). Am grateful for extra practice.