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Norm Matloff 一啲都唔明 Profile
Norm Matloff 一啲都唔明

@matloff

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CS (frmr Stat) em. prof. Awarded #rstats author, 2016. New book: Art of ML. Teach., pub. service awards. Frmr Ed-in-Chief, R Journ. 1st-gen college. Views mine.

SF Bay Area
Joined June 2011
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@matloff
Norm Matloff 一啲都唔明
12 days
@stephsvox @UCLA This is so extreme that one's first impulse is to wonder if it is fake. But yes, all indications (see yesterday's video) are that, sadly, this is the real thing. Again, as a Jewish LA native and UCLA alumnus, I am absolutely amazed both at the students and the administration.…
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@matloff
Norm Matloff 一啲都唔明
2 months
@thestustustudio In which Skadden LLP wakes up to find there are much better candidates at non-Ivy schools. Yet another sad silver lining to the tragedy of the last 4 months.
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@matloff
Norm Matloff 一啲都唔明
1 month
@bethanyshondark @RutgersU "We don't want 2-state! We want '48!" They want the return of the British Mandate? :-)
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@matloff
Norm Matloff 一啲都唔明
4 months
@IraStoll Who is the other co-chair? A mirror image? Either way, seems to me that extremists should have no place on such a task force.
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@matloff
Norm Matloff 一啲都唔明
1 month
@sfmcguire79 She seems to be an amazing woman,
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@matloff
Norm Matloff 一啲都唔明
5 months
#rstats Here I will first introduce the concept of quantile regression (QR), a powerful technique that is rarely taught in stat courses. I’ll give an example from the quantreg package, and then will show how qeML can be used to do model-free QR estimation. 1/
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@matloff
Norm Matloff 一啲都唔明
1 year
Hey, everyone, I'm retiring! I've written a bit on my life history, and my thoughts on education etc.,
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@matloff
Norm Matloff 一啲都唔明
2 years
@DrewPavlou E-mail has a paper trail, from start to finish. Had this been checked, the police would have seen it did not originate with you. Conversely, you could use it now to bring a charge against the embassy of filing a false police report.
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@matloff
Norm Matloff 一啲都唔明
12 days
@MikaelaSkyeSays @stephsvox @UCLA "Just"? I'm sure a whole bunch of laws are being violated.
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@matloff
Norm Matloff 一啲都唔明
5 years
#rstats Yesterday I stated that @MattDowle is one of the most important people in the history of R. Regardless of whether you use #rdatatable or not, it's important that you understand why. 1/n
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@matloff
Norm Matloff 一啲都唔明
6 years
@tcarpenter216 The best advice I ever got on writing (actually from a nonacademic): Write a draft; put it aside for couple days; come back then, read it again, and be horrified :-) ; rewrite. Repeat cycle.
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@matloff
Norm Matloff 一啲都唔明
5 years
#rstats I've been meaning for a while to write a point-by-point analysis of the R vs. Python debate. Here it is:
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@matloff
Norm Matloff 一啲都唔明
3 years
@ZaidJilani Once again we see an ideological school board totally out of touch with the people they supposedly serve.
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@matloff
Norm Matloff 一啲都唔明
2 months
@Hebro_Steele @Stanford @joboaler What she advocates amounts to establishing Jim Crow in California schools. The Data Science course she supports in lieu of Algebra II is populated mainly with Black and Latino students.
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@matloff
Norm Matloff 一啲都唔明
2 years
@minilek @Stanford "As a courtesy, this is to let you know I've called the police on you"?
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@matloff
Norm Matloff 一啲都唔明
1 month
@thegautamkamath Good, but in the vast majority of cases, the kids will be "advised" by their engineer parents or other adults, even researchers in the field.
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@matloff
Norm Matloff 一啲都唔明
8 months
@DrJBhattacharya Even Teddy Roosevelt's "bully pulput" was out in the open, as was JFK's pressuring of the steel makers. To compare those with the feds' clandestine pressuring of the social media firms is absurd.
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@matloff
Norm Matloff 一啲都唔明
5 years
#rstats It's been great that so many people have commented on my "R vs. Python" essay, . I've made various improvements, and will continue to do so as more comments come in and/or I have some new points to add. 1/2
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@matloff
Norm Matloff 一啲都唔明
6 months
I've set up the Web page for my new book, The Art of Machine Learning, . There are resources there, e.g. code, and an explanation of the book's philosophy.
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@matloff
Norm Matloff 一啲都唔明
4 months
@thisischaniece The explanation, even if true, doesn't quite work. They kept insisting they had a "right" not to be filmed.
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@matloff
Norm Matloff 一啲都唔明
3 months
@ryxcommar If it is true, I believe one of the reasons may be that employers have figured out that their existing staff can quickly learn DS through self study, no need for specialists.
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@matloff
Norm Matloff 一啲都唔明
3 years
@ProfJanelleWong Highly misleading claim. Look at the data, which show that the perpetrators are DISPROPORTIONATELY black. Note too that media coverage tends to focus on the violent crimes, as they should. A white teenage who speaks an epithet is hurtful, yes, but not like physical assault. 1/
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@matloff
Norm Matloff 一啲都唔明
3 years
@realchrisrufo Virtually everyone in China, even in the hinterlands, knows that Americans elected a Black president, and now a Black vice president. Most know who Steph Curry and Lebron James are, etc. This video should create a bit of cognitive dissonance, I'd say.
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@matloff
Norm Matloff 一啲都唔明
1 year
@michelletandler "Male with machete is back." What a quote! Friday's WSJ said a downtown office bldg. previously worth $700 now is expected to sell for $60 million. But no one seems to be able to connect the dots.
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@matloff
Norm Matloff 一啲都唔明
9 months
@johnmyleswhite The salient advantage of academia is tenure. When those grad students and post docs go for interviews at a company, they should note what proportion of the workers there are in their 40s or 50s. If it's small, they should ask where THEY will be in their 40s and 50s.
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@matloff
Norm Matloff 一啲都唔明
9 months
@realchrisrufo Really did laugh out loud on this one. Not just white, mind you, but Nordic!
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@matloff
Norm Matloff 一啲都唔明
4 years
@yudapearl I believe the main point of the paper was that stat people assume the data come from a population, while for ML people, the data are the data, period. The ML people, thus less constrained, were happy to tackle hard applications that the stat people wouldn't touch. 1/
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@matloff
Norm Matloff 一啲都唔明
1 year
I've completed a planned update of my fastStat introduction to statistics, and inspired by a Twitter thread today, have added a short section on data privacy.
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@matloff
Norm Matloff 一啲都唔明
2 years
@f2harrell has come out with a radically new R tutorial, rflow The name is short for "R workflow," but I call it "R in a box," everything one needs to begin serious usage of R, starting from 0 background. 1/
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@matloff
Norm Matloff 一啲都唔明
18 days
This is fascinating. I would have thought he'd put down the "mongrel" nature of English (German + French) as "inelegant." But no, to him it's a feature, not a bug. And he likes the prepositions! Good for him--I've always liked to mull break up, break down, break in, break out and…
@bfcarlson
Benjamin Carlson
19 days
In 1977, Jorge Luis Borges, one of the most influential 20th c. Spanish-language writers, told William F. Buckley (whose first language was Spanish) his reasons for feeling, age 78, that English was 'far finer' than his native tongue. Right or wrong, I love his savor for language
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@matloff
Norm Matloff 一啲都唔明
4 years
#rstats I think R beginners should get a good grounding in base-R, whether they go on from there to Tidy, data.table or neither, I fear that many are being taught only the fancy stuff, rendering them helpless on simple, commonplace tasks. For example:
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@matloff
Norm Matloff 一啲都唔明
1 year
@KatyaSedgwick The victim died in trying to fight back for the goods robbed from her. If she felt so strongly about social inequity, wouldn't she have just let them take the goods?
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@matloff
Norm Matloff 一啲都唔明
3 years
@KTVU Ironic -- the sign on the door says "Curbside Pickup Here." Indeed.
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@matloff
Norm Matloff 一啲都唔明
4 months
@kareem_carr Is his wife president of a university? If not, then what is your point? Very disappointed to see you say this.
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@matloff
Norm Matloff 一啲都唔明
8 months
#rstats , on the importance of using a debugging tool: This is a lifelong major issue with me, and I actually wrote a book on it some years ago. If you write R code of more than a few lines, don't use print() as your debugging device! 1/
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@matloff
Norm Matloff 一啲都唔明
4 years
@BethanyAllenEbr Yep, "huge" is an understatement. Sadly, all of this news is being drowned out in the US by the impeaching hearings.
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@matloff
Norm Matloff 一啲都唔明
8 months
Each year around this time, I update , my advice to undergrad students in Computer Science, Data Science and Statistics, esp. first-year students. ("What no one else will tell you")
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@matloff
Norm Matloff 一啲都唔明
1 year
@marktenenholtz Very true in the 8th grade. :-)
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@matloff
Norm Matloff 一啲都唔明
3 years
#Statistics #math #rstats Please read this if you are a California professor in a STEM field. 1/
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@matloff
Norm Matloff 一啲都唔明
5 years
@tslumley At that same session, they reveal the secret that normal distributions don't exist in the real world.
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@matloff
Norm Matloff 一啲都唔明
5 years
@groundwalkergmb @hardsci @deaneckles But that is exactly @hardsci 's point, Gabe. The fact that the GRE doesn't matter much among those who are admitted to grad school doesn't mean that the GRE is irrelevant as one of the factors in admission.
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@matloff
Norm Matloff 一啲都唔明
3 years
@PhDemetri To me, all the really important properties of the linear model are distribution-free. One doesn't need conditional distributions or matrix algebra to teach it either. Writing something like mean weight = a + b height + c age is good enough. 1/
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@matloff
Norm Matloff 一啲都唔明
2 years
The exchange I had the other day with 2 tidyverse supporters here inspired me to collect some data re usage of base-R vs. Tidy in major R packages. I've just posted it to my stat/R blog,
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@matloff
Norm Matloff 一啲都唔明
2 months
@EconTalker The key, usually not considered, is as you say, "They've promised to do this again and again." I would add that their technological sophistication and boldness is apparently much keener than in the past. 31K Palestinian deaths is horrific, but Hamas now seems to have the means to…
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@matloff
Norm Matloff 一啲都唔明
5 years
#rstats for YOU: Ever encountered an R error message like "Couldn't create memory segment of size 3.2G"? Also, more subtly, ever had some code run slowly in spite of little apparent reason? And ever wonder why data.table is so blindingly fast? This post will be on MEMORY. 1/n
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@matloff
Norm Matloff 一啲都唔明
5 years
#rstats Recently a young relative mentioned that the campus R course she hoped to attend was full. What online alternatives did she have? So, I decided to start one of my own! Designed for complete beginners. Have 5 lessons so far.
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@matloff
Norm Matloff 一啲都唔明
4 years
The late Leo Breiman is usually credited with inventing random forests, but actually the idea was proposed earlier by Tin Kam Ho, who called it "random decision forests." Sadly, she is seldom mentioned in lists of top stat/machine learning people, despite her major contribution.
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@matloff
Norm Matloff 一啲都唔明
6 months
@ProfDBernstein The epidemic of imprecise thinking on the Left affects vocabulary, in this incorrect use of the word "doxxing" by the university.
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@matloff
Norm Matloff 一啲都唔明
5 years
#rstats for YOU: Did you know that R's Principle Components Analysis workhorse, prcomp(), is paired with a predict() function? In this post, I'll explain why that is useful. If you don't know PCA or need review, I'll fill you in. 1/n
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@matloff
Norm Matloff 一啲都唔明
3 years
@EricRWeinstein Are we supposed to infer that Obama is no longer welcome at the White House?
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@matloff
Norm Matloff 一啲都唔明
5 years
In each course I teach, I assign a term project, in groups of 3-4. The topic this quarter was to choose a CRAN package and improve its speed by converting parts to C/C++. Several were really excellent; I've chosen this one to display (with permission),
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@matloff
Norm Matloff 一啲都唔明
5 years
@thepointwithlx Cantonese IS Chinese, and is what most HKers prefer. But most HKers can understand Mandarin today. On the other hand, there is so much resentment against inland China that many will not respond to Mandarin. Those from inland should ask themselves why.
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@matloff
Norm Matloff 一啲都唔明
30 days
@ronawang And amwf's are the out-of-state plates, rare. :-)
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@matloff
Norm Matloff 一啲都唔明
2 months
I've been writing about this for many years. The industry has always claimed a "shortage" of software engineers, claiming the solution is to get K-12 schools to improve instruction in STEM--at the same time the industry is laying off older engineers who excelled in STEM in…
@cameron_pfiffer
Cameron 'Quadron' Pfiffer
2 months
My dad has run into this many times. He built two supercomputers (ASCII red + blue), has code in the Linux kernel, built a novel operating system, is a top GPU person, etc. and has been turned down by Nvidia/Google when he had offers for them many years ago
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@matloff
Norm Matloff 一啲都唔明
3 years
@michelletandler @sfchronicle @ShellenbergerMD @nytimes @WSJ It was reviewed in The Economist, Review as titled "A cautionary tale from the streets of San Francisco: A new book shows how well-meaning urban policies have backfired."
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@matloff
Norm Matloff 一啲都唔明
2 years
@StanleyRoberts Sadly, the attacks ARE disproportionately by Blacks. Real (i.e. not just for show) dialog is needed between the two communities.
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@matloff
Norm Matloff 一啲都唔明
3 years
@dabeard @JiayangFan She was the first writer in the mainstream press to expose abuse of the H-1B work visa, long before bipartisan recognition of the problems. See this article quoting @EricRWeinstein
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@matloff
Norm Matloff 一啲都唔明
4 years
@seanjtaylor @karlrohe @daniela_witten I wrote up some points here, , somewhat iconoclastic.
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@matloff
Norm Matloff 一啲都唔明
3 years
@alexandrosM This long thread is not for everyone. But since Malone's name is coming up increasingly often, esp. in political circles, the thread is worth a read.
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@matloff
Norm Matloff 一啲都唔明
5 years
@EricRWeinstein Some years ago, some grad students sued UC, claiming they were workers. Then someone from my campus administration ordered faculty to disagree. Yes, you read this right. Of course, we just ignored them.
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@matloff
Norm Matloff 一啲都唔明
2 years
@Coqui6190 @noahlet @beatrizurdag I still think fondly of my first visit to Hong Kong. Though it was a personal trip, I dropped by the University of HK Stat Dept., no advance notice at all. The dept. chair took me to lunch, and invited me to give a talk. The CUHK saw it, and then invited me too.
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@matloff
Norm Matloff 一啲都唔明
4 years
#rstats I have written some comments on an excellent paper by Brad Efron. Topics include statistics, machine learning, R and Python,
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@matloff
Norm Matloff 一啲都唔明
6 months
@rastokke @FightFuzzyMath Any creative mathematician has automaticity with math facts. It forms a vital base for the creative work. Can't be creative if you have to constantly be distracted by having to look up 3 x 8.
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@matloff
Norm Matloff 一啲都唔明
3 months
@kareem_carr Actually, the claim is accurate and relevant, and your explanation confirms it. If inequities are to be addressed, the root causes must be identified. E.g. if, given a good level of education, hiring is fair, then this identifies the problem as education, not hiring. Then one…
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@matloff
Norm Matloff 一啲都唔明
3 years
Even China, one of the most ideological countries in the world, does not insert ideology into math classes. That should tell us something. 9/
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@matloff
Norm Matloff 一啲都唔明
2 months
@JakeVigdor It cites evidence found by the universities themselves. IMO this is an excellent piece, with an important subtheme that there was a major Bandwagon Effect underlying the original decision to drop the test.
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@matloff
Norm Matloff 一啲都唔明
1 year
@yuanyi_z "We should teach them statistics" has become the standard dog whistle for "We should water math curriculum down." REAL stat would be great, even vital, but it requires familiarity with functions, slopes of lines etc.--which the "reformers" want to omit from curricula.
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@matloff
Norm Matloff 一啲都唔明
3 years
@PhDemetri Students come away thinking normally distr. epsilon is crucial. It isn't. For large n we have approximate normality of beta hat anyway, while for small n the "exact" methods make an assumption that is never true in real life. Students deserve better than what we are giving them.
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@matloff
Norm Matloff 一啲都唔明
1 month
@Twolfrecovery What stands out in my mind was her dismissing crimes such as car break-ins by saying, "Look, nobody got hurt." On the contrary, it is quite traumatic, especially to kids, to find someone has smashed one's car windows and stolen things.
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@matloff
Norm Matloff 一啲都唔明
5 years
@MaartenvSmeden When we released , which argues that neural networks are actually old-fashioned polynomial regression, quite a controversy ensued. The ML people were defensive (to the point of even criticizing the fonts in our paper), but the stat people were happy. :-)
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@matloff
Norm Matloff 一啲都唔明
5 years
#rstats for YOU: As R surged in popularity the last few years, the skeptics developed some slogans, one of which is "Yes, R is fine for informal usage on small tasks, but it's not suitable for production," referring to large jobs run on a regular basis, say every hour. 1/n
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@matloff
Norm Matloff 一啲都唔明
2 months
@dannoyes "Judge Richard Kramer: 'Of course, I'm frustrated [about rampant, largely unpunished crime in SF]. Why do you think I'm living in Napa now? I lived in San Francisco forever.'"
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@matloff
Norm Matloff 一啲都唔明
1 year
@alisonmartino A bit misleading. The mountains in the background are several thousand feet high.
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@matloff
Norm Matloff 一啲都唔明
1 year
For the last couple of years, many of us have been concerned with the proposal to allow Data Science as an alternative to Algebra 2 in CA high schools. Many STEM academics and professionals have signed petitions against the plan. 1/
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@matloff
Norm Matloff 一啲都唔明
3 years
@MaartenvSmeden Linear models run our lives, pretty well if done carefully. If one adds polynomial terms, say up to degrees 2 or 3, one can often compete well with ML algorithms, while still using lm().
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@matloff
Norm Matloff 一啲都唔明
4 years
@melissakchan A more charitable view: The Chinese term for "democracy" can easily be taken as "people-ism," covering at least the "for the people" in Lincoln's famous line. I'd say most Chinese view their gov. in that light (in principle), so it's not just indoctrination.
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@matloff
Norm Matloff 一啲都唔明
2 years
@daniela_witten Ironically, I'm currently reading mathematician Shing-Tung Yau's autobiography, and half the book seems to be about his enemies. I know a couple of the people mentioned as non-enemies (as do you :-) ), rather startling reading.
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@matloff
Norm Matloff 一啲都唔明
3 years
@pnjaban This is the NINTH Circuit, you say? What happened to them?
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@matloff
Norm Matloff 一啲都唔明
1 year
I've just completed fastStat, , a quick intro to statistics for those who've had a calculus-based probability course. Many such people later need to do stat, and this will give them quick access. Modeled after my R tutorial, 1/
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@matloff
Norm Matloff 一啲都唔明
5 years
The recent article , which compared Python and R, contained a very misleading statement. In explaining that, I can make this post a mini-tutorial about parallel computation. 1/n
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@matloff
Norm Matloff 一啲都唔明
3 years
My biggest concern, though, is the proposal's methods of instruction. Teachers would de-emphasize getting the right answer, and would not require students to show their work. Emphasize would be placed on collaborative group work, rather than individual efforts. 6/
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@matloff
Norm Matloff 一啲都唔明
1 month
Jo Boaler speaks out re the charges brought against her . She says "all research used for the [California Math]Framework was thoroughly vetted by an independent party," and that "most of their accusations demonstrating a lack of understanding of…
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@matloff
Norm Matloff 一啲都唔明
13 days
@deb_fillman Excerpt: "I grew up on Obama. Democratic household. I went to his inauguration...[Before my high school teacher told me later on] I had no idea he [Obama] was a terrorist." Mind boggling statement! Well, she's making up for lost time now, I guess. :-( Yes, an Ivy League student.
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@matloff
Norm Matloff 一啲都唔明
5 months
Recently I speculated that Dr. Gay's years of unethically copying research material could be due to her lack of understanding that material. Here prominent stat prof Andrew Gelman says this too, more forcefully. 1/
@StatModeling
Andrew Gelman et al.
5 months
Plagiarism means never having to say you’re clueless.
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@matloff
Norm Matloff 一啲都唔明
5 years
@isaacstonefish Not the first time that Brookings' "pay for play" policy on their so-called "research" has been exposed..
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@matloff
Norm Matloff 一啲都唔明
2 months
@realchrisrufo I continue to believe that the "grievance industry" people view a PhD as simply a "union card" needed to practice their trade. It's not the classical pursuit of intellectual inquiry. Thus "shortcuts" are not surprising, though still disappointing.
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@matloff
Norm Matloff 一啲都唔明
3 months
#rstats Torch for R is now in the qeML package. I’ve added a new function, qeNeuralTorch, to the qeML package, as an alternative to the package’s qeNeural. It is experimental as this point, but usable and I urge everyone to try it out. In this post, I will (a) state why I felt…
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@matloff
Norm Matloff 一啲都唔明
9 months
@StanleyRoberts @FosterCityPD @MrBadlyTV While there are legitimate concerns re "driving while black," stopping a car with blacked-out license plates is legal and highly justifued.
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@matloff
Norm Matloff 一啲都唔明
2 years
@joboaler Prof. Boaler, none of the entries in your table addresses the very grave issues I describe in Your comments would be greatly appreciated.
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@matloff
Norm Matloff 一啲都唔明
2 months
@stephaniemlee "...Youcubed, a Stanford research center that she co-founded to provide free teaching resources": YouCubed is a "revenue generator" for Stanford. They do have some free materials, but they charge fees, e.g. $995 per person for a summer workshop for teachers…
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@matloff
Norm Matloff 一啲都唔明
2 years
@DGTam86 In almost any city in the world, there are lots of McDonalds.
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@matloff
Norm Matloff 一啲都唔明
3 months
@lpachter :-) Once at a conference I got to a session early, and sat in the front row. Rather large lecture hall. I saw a janitor enter the room, dressed rather shabbily. Then I noticed that the janitor was walking toward me, getting closer and closer rather than veering off. Then he sat…
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@matloff
Norm Matloff 一啲都唔明
2 months
@Pal_action It's an interesting question, whether victors in war have "rights." Questionable, I guess. But the entire history of the Middle East is riddled with victors exerting such "rights." The "owners" of Palestine before the British, the Ottomans, did so, for instance. For that matter,…
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@matloff
Norm Matloff 一啲都唔明
3 years
I urge CA STEM professors to sign a letter that will be delivered to Gov. Newsom, regardless of where you are on the political spectrum. Only an organized effort can have an impact. 10/10
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