jj12345
Are you talking about more than one experimental design in terms of comparing the exp/control distributions or something else?
Edit: Further clarification - I think I'm unfairly generalizing this to a mix between coroutines and an Observer pattern.
As a sibling comment mentions, it's relatively easy to verify your answer for correctness in some cases. The downside of this is that it becomes difficult to assess whether students are actually learning. One way to mitigate this is to withhold answers and assist with other teaching resources like TAs. This also helps teach the aforementioned 'verification' step.
MOOCs for purely pedagogical reasons are sometimes hard to find in ML, not only for the aforementioned reasons, but creating a MOOC is simply resource intensive. It follows that many of the producers that truly value education are actual universities. Hybrid models like Coursera and Udacity are still trying to figure out how to get out of the red.
All of this to say that I'm still very grateful for content creators who go beyond simple framework tutorials.
- I've found the rigor to be significantly more than most MOOCs, inline with other traditional grad courses I've taken.
- Some classes are hybrid, sharing the term with on-campus students.
- Not having finished the degree, my work as a data scientist has significantly benefited from the coursework. This is not to say that it wouldn't have benefited from other, non-GT coursework.
[1] https://www.safaribooksonline.com/library/view/head-first-py...
When she's discussing Compensations she mentions that the Transaction (T_i) can't have an input dependency on T_i-1. What are some things I should be thinking about when I have hard, ordered dependencies between microservice tasks? For example, microservice 2 (M2) requires output from M1, so the final ordering would be something like: M1 -> M2 -> M1.
Currently, I'm using a high-level, coordinating service to accomplish these long-running async tasks, with each M just sending messages to the top-level coordinator. I'd like to switch to a better pattern though, as I scale out services.
That being said TimeLion has been great for doing some basic exploratory work.
Just thinking out loud here:
The typical case where a low dimensional representation would fail you is if you had dependencies (e.g. bimodal relations) that weren't represented by a datatype or foreign key. Recall that the simulation of data still occurs within each table, so the higher the non-represented inter-table dimensionality is, the supplied distributions can measure it. It's might be that, for the most part, the raw columns (not from child tables) have much more bearing on the merit of the table covariance. This seems natural, due to the semantic nature of RDBMS structures.
It's probably an important caveat that typical RDBMS structures are created to optimize the user's understanding of the data through semantic structure. Since the claim of the paper was only that they could provide a useful abstraction for simulation, I think it's OK to proceed with the assumption that Gaussians can never be fully sufficient in modeling highly dimensional data without help.
There are existing non-parametric models that attempt to do a similar thing for relational data that I think are more promising. One drawback of current solutions like BayesDB is that you're still dealing with the original table structure, which this paper tries to get around. It would be nice to bridge the gap for something like PyMC3 where we find a cute way to flatten the data, like this paper.
[1] Probabilistic Search for Structured Data via Probabilistic Programming and Nonparametric Bayes. https://arxiv.org/pdf/1704.01087.pdf
Peeling back the mystery a bit, what is happening is:
1. From each child table upwards, model each column as a simple distribution (e.g. Gaussian) and covariance matrix.
2. Given those child table distribution parameters, pass them back as row values to their respective parent tables.
What you end up with is a "flattened" version of each parent table that has the information (in an "information theoretic" sense) of all child relations. Sampling from distributions is straight forward. The stats methods are outlined in section 3 of the paper.
Things of note:
- The paper makes heavy use of Copula transformations to normalize data whenever it passes around the distribution parameters.
- It deals with missing values by adding something like a dummy column.
- The key insight is that columns must be represented by parameterized distributions, but they don't have to be Gaussian. The Kolmogrov-Smirnov test is used to choose the "best fit" CDF to model.
To your question about the role of the data scientists: they are using the resulting simulations to solve more complex tasks. The goal of the experiment was to see how well the sample data would perform against Kaggle competitions. So I guess the idea was that if winners were indistinguishable, the simple/hierarchical distributions would be considered robust enough for complex tasks. In the end, I'm sure shipping the underlying is preferable for consumers.
Thanks again!
On the paper, I was hoping you could help me understand a few things: - It seems that the main finding is that any k-CNF form, like Thomas' Boolean Regulatory Network, can be expressed by PAC learning bounds. In section 4 of the abstract [1], you mentioned that "when the dimension increases... the PAC learning algorithm can leverage available prior knowledge...". Are you referring to the time dimension adding more clauses to the k-CNF? - I'm having trouble reconciling the PAC term "h" with "model confidence" in section 5.2. Is this allowed because the PAC learning "delta" (probability) [2] parameter is dropped for the k-CNF adaptation? - In this concrete case, is the learning portion just the mapping the stochastic traces to outputs (i.e. lookups)? I'm missing some understanding on how such a mapping handles stochasticity.
You'll have to forgive me, as I'm still trying to understand the paper. It's incredibly interesting to me, so thanks for writing it!
[1] Abstract - http://mlsb.cc/2017/abstracts/MLSB_2017_paper_11.pdf
[2] PAC Learning - https://en.wikipedia.org/wiki/Probably_approximately_correct...
On a separate note, AIC/BIC are prevalent in linear regression models because they are extremely well-behaved in comparison to some other models. This has generated enormous amounts of field-specific experimental literature. For instance, economists can form expectations for AIC/BIC measurements dependent on the study-type.
Additionally, we already have some decent tools for regularization (albeit model-dependent ones). Counting the nodes of a NN to establish an AIC may not lead to a proper understanding of the free parameters.
This wasn't meant to be an apologists take on why I'm not using AIC/BIC for model selection. If we're talking about "deep learning", then it's definitely a worthwhile goal to examine how to optimize network topologies. The link below mentions using reinforcement learning to learn architecture.
https://research.googleblog.com/2017/05/using-machine-learni...
Just looking for clarification because I feel like I should know this. Trying to couch the problem in terms I'm more familiar with.
I'm still going through Yoshua Bengio's new book on DL, but if anyone is free to comment: what are the justifications for the general architecture? Why use LSTMs with the Glove embeddings?