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I cannot continue reading after this following “declaration”… Author should take a look at the Wikipedia page for TF-IDF. > As someone who has a Ph.D. in Human
by ekzhu 5y ago
I cannot continue reading after this following “declaration”… Author should take a look at the Wikipedia page for TF-IDF.
> As someone who has a Ph.D. in Human-computer Interaction ;-), I feel like I am entitled to define a condition of "good" in relevance here. I hereby declare that:
>> A good top-K algorithm should rank a document containing more user query terms higher than a document containing less number of user query terms.
> This makes perfect sense. Right?
Also, “most search engines” don’t use vector space model as the only way to rank result, for example, page rank.
Edit: in some search scenarios finding the documents with the most query terms make sense, but Lucene can also rank using this metric. Still, applaud the author's effort in digging into research literature. Search relevance is very hard and standard off the shelf metrics like TF-IDF and page rank are often not enough. Good search usually requires deep understanding of the specific subject domain and hand-tuning tons of signals, many of which aren't even strictly based on search terms (e.g., previously purchased products on a store's website, geographic location, trending results).
- rory_isAdonk 5y agoYeah beyond the cringe of thinking a Ph.D really means anything, its just highlights the pure lack of Lucene knowledge.
- speedgoose 5y agoA Ph.D means a lot for many people. It's years of work to make the science progress a tiny little bit on a topic you enjoy (supposedly). I think it's a lot harder and meaningful than writing scalable and reliable code as a team in a software company, just to give one example to compare with.
- tgv 5y agoBut a phd in HCI has very little relevance to information retrieval or computational linguistics.
- johncearls 5y agoExactly this. I have a PHD in CS and am a world class expert in multi-omic data integration and analysis. I'm happy to throw my weight around in that area, but I'd never point to my PhD to pontificate on Neural nets or systems or queuing theory or 99 percent of CS. If getting a PhD doesn't teach you how much you don't know and how hard it is to develop real expertise in any area, I think you wasted your PhD. Note, my PhD isn't on the value of PhDs so take it as you will.
- huahaiy 5y agoI think I am pretty qualified to make my declaration, since it is about user experience. I also do know a lot about IR, because I taught Information Retrieval class for 3 years when I was teaching in university, I read research papers, and I just come up with a new search algorithm. It's just that some people cannot accept that there are people who can cross fields with ease, make contributions quickly, and move on to the next field that pit their interests. Yes, I am one of those people. In addition to HCI, I also published in the following areas: VR, DB, NLP, IR and Psychology. Sorry to hurt your feelings, but it is what it is. Accept it and move on.
- tgv 5y agoThat's not a new search algorithm. It's about the second one people have come up with. First version: all documents containing all search terms. Second version: counting frequency in document. Since you taught IR for three years, I'm surprised there's no mention of other relevant heuristics, or measuring against benchmarks.
- huahaiy 5y agoAgain, you miss the novelty of the algorithm due to your smugness. I have updated the article to point out explicitly where the novelty is at. You completely ignored that. In fact, I believe you didn't even read that far before your jumping out to write this dismissal. I wrote a blog post for lay people to read. I am under no obligation to do an extensive literature review, I only need to mention the essentials. You just cannot seem to swallow the fact that someone who does not have a Ph.D in IR or computational linguistics can come in to contribute quickly then move on to something else. It hurts your feelings deeply, does it? Heed my advice, just get over it, don't take your degree or your specialization too seriously. It does not matter.
- marcellus23 5y agoWell it’s certainly more meaningful to the person who has one.
- Cthulhu_ 5y agoWell yeah, but it shouldn't make you smug. A Ph.D, while not the beginning, is definitely not the end, and the people we look up to as Really Smart never sat on their laurels and quit learning, never considered themselves above others.
- juancb 5y agoIt's fascinating seeing what hacker news thinks is smug. There are plenty of actually smug comments that go without being called out but for some reason this guy does. The PhD flex in jest by the blog post's author is a bit awkward but I don't know that I would characterize it as smug. Any insight into why the author is perceived as smug would be appreciated.
- taeric 5y agoAgreed. The wink right after it, I would have thought, dulled any smugness. I could see calling it audacious. But, our industry advances on audacity.
- huahaiy 5y agoRight, I thought that the wink is enough, and I have also paid enough homage to Lucene. What's wrong with people? I think a lot of them are probably just university students who have nothing better to do than to troll on Internet.
- huahaiy 5y agoLet me offer my arguably biased insight: racism. I am obviously a Chinese. In the eyes of racists, Chinese Americans are supposed to be timid and does not make any noises, but I do make noises, so I am perceived as a smug today because I said I am a Ph.D, something else next time I said something else. It's not complicated.
- throwaway744678 5y agoWow, I was with you until this. I, for one, never even suspected your origin or nationality reading the blog post. OK, re-reading it, there are a few hints (a Chinese proverb, your nickname, etc.). But nothing "obvious". Probably not the explanation we are looking for here.
- Cavallium 5y agoI also suggest you to look at his "benchmarks" code
- huahaiy 5y agoThe benchmark is fine. Your so-called "fundamental" flaws are just superficial things, such as using a different time measure, using a different benchmark library, passing in a thread pool, and so on. These are immaterial to relative comparison, unless proven otherwise. I have repeated asked you to send the code that does things properly in your mind, and you refused to do so. So you are just trolling. Please stop hinder the progress of the industry through pointless trolling. Makes some positive contributions instead, and I have pointed out repeatedly how to make a positive contribution in this case. Please do. You are a university student, I am a seasoned computer scientist, past researcher and professor, I am busying running a startup. This will be the last time I will say this to you: please consider contributing something positive to the world.
- softwaredoug 5y agoAs author of Relevant Search and contriburor of AI powered search I endorse this :) Relevance is really subjective, domain specific, requires intense amount of measurement and testing and many different ranking signals. Lucene is a toolbox for crafting many of these signals.
- softwaredoug 5y agoOn second read-thru, I think the author is maybe(?) describing assumptions behind WAND and relevance algos that benefit from it? Maybe not some overarching statement about relevance per-se? But it's mixed in with statements about relevance / what Lucene does that are mostly incorrect... For example, he says > However, as you can see, this vector space model does not explicitly require a higher ranking document to contain more query terms than a lower ranking one. Well the way you get a higher similarity in a vector-space model is matching more terms. The caveat being that IDF and field length makes you also consider a term's specificity. So if you search for 'luke skywalker' you care more about the 'skywalker' match than the 'luke' match. But a match on BOTH 'luke skywalker' would score higher (field lengths being constant)
- huahaiy 5y agoThere's no guarantee in pure vector space model that it is the case. Your understanding is way off. This is a caveat that Lucene prominently put on their Web page. https://lucene.apache.org/core/3_5_0/scoring.html https://lucene.apache.org/core/3_5_0/scoring.html "Lucene scoring is the heart of why we all love Lucene. It is blazingly fast and it hides almost all of the complexity from the user. In a nutshell, it works. At least, that is, until it doesn't work, or doesn't work as one would expect it to work. Then we are left digging into Lucene internals or asking for help on java-user@lucene.apache.org to figure out why a document with five of our query terms scores lower than a different document with only one of the query terms." See? Lucene people know about it but they just do not think it is a problem. But I do. T-Wand, though also uses vector space model, makes sure it is the case.
- softwaredoug 5y ago
- huahaiy 5y agoIt's your loss then. It is actually smug, to suggest the author, in this case, me, a computer scientist and a past professor who taught Information Retrieval class for more than 3 years, and who just came up with a new search algorithm, to "take a look at Wikipedia page for TF-IDF". In case you have not read the article due to your smugness, my search algorithm also uses TF-IDF and vector space model. Please do not dis-understand what is going on here: I am running a startup, and I am also old enough to not care about publications as much as people who are younger or in academia. That's why I chose to reveal this in a blog post instead of hiding it until after my paper is published. Understood?
- antocv 5y agoHaters gonna hate, dont mind them. Your work is truly amazing, I learned a lot and you opened a whole new world of datalog as an aside.
- huahaiy 5y agoThank you. I am glad that you learned something from the article. I wrote the article for people like you, who are seeking knowledge and self improvement.