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scottedwards

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into statistics, machine learning, python, search engine marketing(SEM), SQL, data warehousing, OLAP, ETL, datamining

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I feel your pain. I was lucky enough to be around to enjoy the days when the ONLY place online where people were discussing serious topics (and non-serious ones!) was USENET (and maybe The Well). Google Groups just started to throw a web interface on USENET.

Sadly, once big money entered the Web in the late 90's, every Portal popping up felt like they had to include discussions/message boards into their features.

Yahoo Groups was big in the day and is now essentially dead. Same with Facebook, etc.

Now everything is very fragmented. There are some really great discussions happening out there (metafilter.net is a good example) but they are hard to find.

Reddit might be the closest thing to a groups/USENET replacement that we have.

I'd love to hear about anything else out there that may save civil discourse, but I have my doubts it exists (or will). (although web3 may save us yet - nostr is pretty interesting)

After all, what does it mean when 90% of people spend their time on Instagram and Tiktok?

Thanks, this was exactly the kind of finding i was asking for. So, at least at this stage of life, sounds like majority of your cohort is still employed. I wonder if that will hold up ten years from now.

I guess what I'm really worried about is that many are somehow "forced" into retirement or low paying jobs (ala Walmart greeter). This would seem really unfair, given that on the surface, this kind of age discrimination shouldn't happen. At least the military is up front about how this works with it's "Up or Out" policy.

Thanks for your comments guys, but if this is true, why don't I see more workers in their 40s, 50s, and 60s around? (and I'm not specifically speaking of devs, although the effect seems more drastic there).

And I don't work at a startup - this is the 2nd large company (>20k employees) I've worked at, and in both cases, I would say that the percentage of workers over 50 is less than 10% - and most are managers or senior folks.

My question is simple - where the heck did all these people go? I don't think the mortality rate is that high ;-) and I doubt many people can afford to retire that early.

Have to agree. And it's very inexpensive because Yaser refused to give-in to academic publishers, who would've charged the typical $70-80, and self-published so he could offer it for less than half the cost.

Not only is the book great, but his lectures are PHENOMENAL. He breaks concepts down in such a careful, accessible way. Its a bit late to join the online course, but you can see all the lectures on YouTube (work.caltech.edu/telecourse.html) or iTunesU (I prefer the latter, using the app on iOS - awesome b/c you can bookmark and record notes at those marks - otherwise I notice these video types of courses are way less useful - no way to review - wish Coursera/Udacity/EdX had that feature.)

Yaser is an awesome guy btw - he's very active on the forum (see the link from the above caltech site - on right hand side). He is very gracious with his time - I'm not a CalTech student, and yet he has answered all my questions and even helped me find a tutor for the course that was a previous student at CalTech (I live in Pasadena). He truly cares - and that comes off in the lectures as well. Enjoy!

Thanks, @gtani, great resource. Yeah didn't mean to imply that ML techniques are free of ANY assumptions, just that several of the popular ones like logistic regression don't have distributional assumptions. (actually, I really want to understand the VC Inequality at some point, as it seems to allow us to make conclusions about out of sample error rates without depending on distributional assumptions)

Great suggestion. I've been amazed to find out that many coders and amateur "data scientists" don't realize that testing the assumptions is an important part of conducting statistical analyses. Part of this may be due to the recent emphasis on machine learning techniques, which tend to be assumption-free (often just assuming independence of cases in the sample).

Great effort, and I certainly hope more coders will get into statistics (most I know are only interested in machine learning). However, I think your definition of 1.3 "Confidence Interval around the Mean" could be improved. You state:

"A confidence interval reflects the set of statistical hypotheses that won't be rejected at a given significance level. So the confidence interval around the mean reflects all possible values of the mean that can't be rejected by the data."

That seems a bit vague and perhaps confusing. Might I suggest something more like this:

"The confidence interval specifies a range (+/- a multiple of the above standard error [SE]) around our estimate of the mean (x-bar) such that: if we repeated our sampling process an infinite number of times (i.e. with the same sample size and forming a new x-bar and SE each time [and therefore, a new confidence interval]), Confidence_Level% of those intervals would contain the population (true) mean."

In addition, I think in this case, at least, there are no assumptions about the data to worry about, given a sufficiently moderate sample size due to the Central Limit Theorem (I'm confident about that in the case of the mean (x-bar), but I'll leave it up to others to correct me if I'm wrong about this applying to the standard error (SE)).