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What are Bloom filters?

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Re: What are Bloom filters?

#31

Like everyone else, I too wrote a blog post on Bloom Filters - http://prakhar.me/articles/bloom-filters-for-dummies/ .

I preferred yours, but I'm not sure what you had for dinner on your last birthday.

Haha! What is that supposed to mean? :D

Re: What are Bloom filters?

#32
post #13

>To understand Bloom filters, you first have to understand hashing. As pedagogy, I think this is the wrong approach. The author already knows Bloom filters and therefore, it seems like the most logical thing to first talk about is hash functions because that's how it's implemented . Unfortunately, that's not how a person brand new to the concept thinks about it. The first thing to talk about is motivations and scenar…

wow yes, this is an issue with nearly every technical conference talk

In my experience, more specifically with talks about functional programming techniques. I find them completely impenetrable.

Re: What are Bloom filters?

#34

Earlier quoted context omitted.

I preferred yours, but I'm not sure what you had for dinner on your last birthday.

Haha! What is that supposed to mean? :D

You didn't include non-important life details when explaining what a bloom-filter is.

>I sigh. I’m hungry and the main course has just arrived — venison glazed in honey, served with a sweet potato hash.

I learned more about what the author had for dinner on their last birthday than I did about bloom filters in the first paragraphs.

So while they prefer your blog - they aren't sure what you had for dinner on your last birthday...

Re: What are Bloom filters?

#35
post #25
post #13

>To understand Bloom filters, you first have to understand hashing. As pedagogy, I think this is the wrong approach. The author already knows Bloom filters and therefore, it seems like the most logical thing to first talk about is hash functions because that's how it's implemented . Unfortunately, that's not how a person brand new to the concept thinks about it. The first thing to talk about is motivations and scenar…

I'm fine with explaining the motivation first, but I struggle to see how you can explain bloom filters without eventually getting to hashing. Obviously you don't need to explain any actual real-world hash function, but you need to explain the concept of deterministically mapping X bits to Y bits where X > Y, which is essentially what a hash function does.

[deleted]

Re: What are Bloom filters?

#36
post #13

>To understand Bloom filters, you first have to understand hashing. As pedagogy, I think this is the wrong approach. The author already knows Bloom filters and therefore, it seems like the most logical thing to first talk about is hash functions because that's how it's implemented . Unfortunately, that's not how a person brand new to the concept thinks about it. The first thing to talk about is motivations and scenar…

Pedagogy? No, this article is written in that modern style of popular non-fiction which is meant to entertain above all other concerns, including such silly things as pedagogy, clarity, rigor, or sometimes even factual correctness.

This style is characterized by titles like "Catchy Phrase: The surprising tale of a subtitle that actually tells you what the book is about. Or does it?" "Catchy Phrase" tells the story of an single data point, or maybe three, with edge-of-your-seat tension provided by a jumbled chronology. It opens a generation before the main data point was born, then skips to the present day, before jumping into the middle of a tangential story. Then it's back to where we left the origin story of the data point, but this time we're in a different location looking at the second data point. Next comes some speculation about a possible rosy future and maybe a motivating example. Next we end the tangential story, which introduces the third data point, at it's funeral. The tangential story begins. As you read, you can see a complex theme slowly but deftly woven from the timelines of the several stories. It's a pattern that a knitter might call "felt". You can't help but be drawn in. It's so fascinating and intricate that you, like the author, sometimes have trouble distinguishing cause from effect, which adds an alluring air of mystery. The ideas must be Important. Despite the complexity, in the end the conclusions seem simple and obvious. You feel smart. You go to a dinner party and gush about it to your friends. They wake up the next day and, despite one-too-many cocktails, find that they remember the title of "Catchy Phrase". They look it up, and One-Click (tm) later, the life cycle is complete.

You aren't the audience, you're the vector.

Re: What are Bloom filters?

#37

I'm beginning to suspect that if I want to really drive a whack of traffic to my blog, I should write a post about how to implement Bloom filters using monads.

For maximum impact, you'll need to choose your programming language carefully. I would suggest Elm with a sprinkling of Coq, though I think using either K or MUMPS would earn you a lot of kudos in some quarters.

Re: What are Bloom filters?

#38
post #4

Can anyone give some cases of where Bloom filters are used? Has anyone used one in their job?

Yes! We use them to check for weak passwords server-side. (Passwords arrive already hashed, we have a large dataset of known bad passwords that we load when the application starts.)

https://github.com/lavab/api/search?utf8=%E2%9C%93&q=bf

Re: What are Bloom filters?

#39
post #28

Is anybody else irritated with the incredibly tryhard tone in this article? "venison glazed in honey, served with a sweet potato hash"? Seriously??? It's an article about bloom filters for god's sake, not Leveraged Sell Out for the tech industry...

Much like most TED talks, this is in line with the common Medium article theme. The article becomes more about ME ME ME, rather than the subject at hand. It's like some Moses syndrome.

When it comes to technical articles this starts to become extremely annoying to read blogs/papers as if it was written for BuzzFeed.

Re: What are Bloom filters?

#40
post #28

Is anybody else irritated with the incredibly tryhard tone in this article? "venison glazed in honey, served with a sweet potato hash"? Seriously??? It's an article about bloom filters for god's sake, not Leveraged Sell Out for the tech industry...

I couldn't make it through. I was thinking about Bloom filters just earlier today and was actually looking forward to reading about them. I'll try again tomorrow with a different author.
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