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Cognitive psychologist / data scientist!

Working on siuba, a data analysis tool for python:

https://github.com/machow/siuba

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Plotnine 29 days ago

Hey! I worked on the plotnine guide (https://plotnine.org/guide/). Always interested to hear what people find hard to understand about plotnine, or what they wish there were more of (e.g. examples, guide pages, api reference docs).

(Both has2k1 and I work for Posit, which supports plotnine work, but authoring its guide was mostly an act of passion for me :)

I have used numpy, but don't understand what it has to do with dataframe apis

Take two examples of dataframe apis, dplyr and ibis. Both can run on a range of SQL backends because dataframe apis are very similar to SQL DML apis.

Moreover, the SQL translation for tools for pivot_longer in R are a good illustration of complex dynamics dataframe apis can support, that you'd use something like dbt to implement in your SQL models. duckdb allows dynamic column selection in unpivot. But in some SQL dialects this is impossible. dataframe apis -> SQL tools (or dbt) enable them in these dialects.

I think it's often a syntax convenience. For example, Polars and Pandas both have DataFrame.pipe(...) methods, that create the same effect. But it's a bit cumbersome to write.

Here's a comparison:

* Method chaining: `df.pipe(f1, a=1, b=2).pipe(f2, c=1)`

* Pipe syntax: `df |> f1(a=1, b=2) |> f2(c=1)`

I think piping and method chaining are a little bit different.

Piping generally chains functions, by passing the result of one call into the next (eg result is first argument to the next).

Method chaining, like in Python, can't do this via syntax. Methods live on an object. Pipes work on any function, not just an object's methods (which can only chain to other object methods, not any function whose eg first argument can take that object).

For example, if you access Polars.DataFrame.style it returns a great_tables.GT object. But in a piping world, we wouldn't have had to add a style property that just calls GT() on the data. With a pipe, people would just be able to pipe their DataFrame to GT().

It's neat to see tablets discussed in the context of modern tools. I recently helped edit an article for Great Tables[1] that discusses the history of tables like this, and recently Hannes mentioned a protocuniform tablet in his duckdb keynote at posit::conf()[2].

There's something really inspiring from realizing how far back tables go.

[1] https://posit-dev.github.io/great-tables/blog/design-philoso...

[2] https://youtu.be/GELhdezYmP0?si=bSISmFjeRpKxfLWq

This is an interesting case, since the pigeon study is about what happens when the underlying process is random.

But if the shape drawing process isn't random, I think the author's experience of feeling unable to articulate the rules AND gravitating to a set of behaviors is a good example of procedural memory (implicit vs explicit).

Explicit rules would probably help speed things up, though!

As someone who did statistics and psychology, I'm very surprised by this take, for a few reasons:

1. Many of the early pioneers in statistics were psychologists.

2. The econ x psych connection is strong (eg econometrics and psychometrics share a lot in common and know of each other)

3. Many of the people I see with math chops trying to do psychology are bad at the philosophy side (eg what is a construct; how do constructs like intelligence get established)

From a more applied angle, a book like "10 steps to complex learning" might be helpful.

I come from a similar cog psych background as the Bjork Lab, so am a big fan of their research, but books like 10 steps come from instructional design, which is a bit more focused on the big picture (designing a whole course vs individual mechanisms).

Hey one of the co-maintainers of Great Tables, along with Rich Iannone, here!

I just wanted to say that Rich is the only software developer I know, who when asked to lay out the philosophy of his package, would give you 5,000 years of history on the display of tables. :)

People questioning the headline are missing the point of the underlying article.

The underlying study is not about just rate of learning, but rate of learning under favorable conditions.

The article describes where the data comes from:

In particular, we model learning using 27 datasets with over 1.3 million student performance observations from 6,946 learners in 12 different courses ranging across math, science, and language learning, across educational levels from late elementary to college, and across educational technologies including intelligent tutoring systems, educational games, and online courses

And the authors argue this is favorable learning conditions because of providing things like immediate feedback on errors, etc..

Lots of room for nuance, but "favorable learning conditions" is key here.

https://www.pnas.org/doi/10.1073/pnas.2221311120

Having had the great pleasure of refactoring a few python libraries, I've had to encouraged people to switch away from inheritance.

You often get a ton of methods / attributes on the child class, which gets hard to keep tabs on. You have to be careful not to use the same names for things. (The worst is that someone uses this broken encapsulation and relies on things across parent classes via the child).

I get that inheritance can go okay for simple cases, but have seen enough chaotic uses of it that I'd just encourage people to write the boilerplate for forwarding methods.

It seems like this is a lot of the strategy behind pitching things as epics. If tweaks interact to produce considerable satisfaction / delight, then bundling them together keeps focus on what big thing happens when they're all completed..!

The issue is that sometimes a function can take a type that is an optional dependency, so you don't want to import it unless you are type checking.

(And some types are defined in the typeshed so only exist to be imported during type checking; eg the type checker lib itself is a dependency in this case)

Doctests in R 4 years ago

One interesting thing about R examples is their outputs tend to be bigger. I think this is in direct contrast to python docstrings, where outputs are very concise--because you manually include the output for doctest.

I wonder if a challenge for doctests in R is they often have to test larger, more realistic outputs?

For example, in dplyr's mutate doc, one example is this:

  starwars %>%
   select(name, mass) %>%
   mutate(
     mass2 = mass * 2,
     mass2_squared = mass2 * mass2
   )
This example's output is a dataframe with 4 columns and will display first 5 rows.

On the other hand in siuba (a port of dplyr to python), I often have to truncate the example output, because it's hard coded in the docstring:

  (cars 
    >> mutate(
      cyl2 = _.cyl * 2, 
      cyl4 = _.cyl2 * 2
    )
    >> head(2)
  )
     cyl   mpg   hp  cyl2  cyl4
  0    6  21.0  110    12   24
  1    6  21.0  110    12   24

It's nice you can see the full example in the docstring in python, but also very handy seeing complex examples on R doc pages:

https://dplyr.tidyverse.org/reference/mutate.html#ref-exampl...

As a person learning cantonese, pycantonese and cantonese.sheik.co.uk were so helpful!

The trickiest thing to explain to people is that Cantonese is a diaglossika. It's spoken, but to write you would use mandarin. So there aren't a ton of giant written language corpuses to train on.

AFAICT that's why tools like this often use simple heuristics to do word segmentation. I remember going down a deep rabbit hole, before finally just packaging a small tool to do cantonese word segmentation using the A* algorithm:

https://github.com/machow/cantocut

FWIW extreme groups (e.g. using upper and lower quartiles) is well understood in its inflation of effect size (there are even formulas to correct this, given an extreme groups design).

It's definitely related to ecological fallacy in the sense that both underestimate relative error and inflate effect sizes.

I used numpy a lot for my PhD research, and think you're right, in the sense that things could have been much more numpy array centric (just like how in R the dataframe is a tiny structure around arrays).

There are a lot of problems you encounter when using arrays for data analysis, like some of their funky behavior with strings [0], but it seems like extending arrays, or building new types of numpy arrays would have been better than new data structures like the pandas Series.

(pandas folks thought a lot about these problems so I could be very wrong).

[0] https://mchow.com/posts/pandas-has-a-hard-job/

Author of the post and siuba here. I'm pretty interested in exploring supporting polars as a backend, and if it works well supporting versions of the SQL backends that translate to SQL based on the polars method API :).

(I haven't really used it, but it looks promising)

Author here. My concern in the article isn't that you can't do groupby fast, but that the approach above is not composable.

* If f() converts grouped data to something ungrouped, then you can't use a similar function f2(f(group))

* If f() returns a grouped object, then you can't do basic operations like f(grouped) + 1, because DataFrameGroupBy, SeriesGroupBy do not define basic operators like addition. Let alone operations against other grouped data.

A lot of this is worked out in siuba now, and this doc explains a bit more:

https://siuba.readthedocs.io/en/latest/developer/pandas-grou...

I've been working on using github projects beta for the past couple months. I'm super excited for it, but right now it's hard to use because because it lacks basic features.

Things projects have that beta projects don't:

* No easy way to automatically add issues from a repo to your project. You have to add them one by one, or use the graphql API, which lacks batch operations.

* No issue preview on the board.

Basic feature missing from sheet view:

* You can't sort issues along the dimensions available in a repo's issue tab (e.g. newest, oldest, recently updated).

I thought I must have been missing something, until I realized that github's public roadmap repo itself uses a bot to add issues [0]. There's an issue there listing out the parity items [1], which will be super handy!

[0] https://github.com/orgs/github/projects/4247/views/1

[1] https://github.com/github/roadmap/issues/287