Posts10 Collaborative Filtering (user-based, item-based) notes User-based collaborative filtering We predict unknown rating of a user based on the ratings of other similar users. Given a rating matrix, to predict user u's rating on item p by taking a weighted sum of ratings of other users who rated p (either all other users that rated p or top k similar users who rated p). The weight is similarity between u and the other user u', computed based on cosine si.. 2022. 10. 23. Community detection notes Girvan-Newman This approach defines communities by cutting most-traversed edges (until we form k communities). We identify most-traversed edges by counting how many times an edge is traversed as part of shortest path from a node to another node. If the shortest path from i to j covers an edge (a,b), then edge-betweenness increases by 1 due to that path. BUT if there are q shortest paths from i t.. 2022. 10. 22. Reservoir Sampling and Bloom Filter notes Reservoir Sampling Reservoir sampling is sampling technique from a stream of elements. It makes sure that the probability of an element remaining in a sampling of size s after encountering m elements from the stream is s/m. Reservoir sampling with sample size of 1 ensures that any element from the stream gets picked into the sample with a probability of 1/m (that is, after encountering m element.. 2022. 10. 19. Universal hashing and minhash notes 1. Universal hashing (W2.2) We have numbers from a large set S, which we want to store, query, and remove. Our requirements are: - time complexity of O(1) - space complexity that's less than O(|S|) Deterministic hash functions (maps S -> {0,n-1}, n 2022. 10. 18. Atlassian grad process - 1. CV and Hackerrank This is the first in the series of Atlassian grad process. 0. Motivation Due to a popular demand and interest, I have decided to write some blurbs about what the Atlassian interview process entailed. No, I'm kidding, noone really asked me for this. However, I previously did come across a random post that detailed their interview process that gave me a real insight into what the interviews are ac.. 2022. 8. 3. ENGGEN 403 - about grit and growth mindset Perhaps one phrase that struck me while listening to ENGGEN 403 lecture is that we often make the mistake of thinking about tyranny of now instead of thinking about the power of yet. We are scared by the results we will receive in our recent examinations, rather than thinking about what I want to achieve in the long term and contributing to the society in a meaningful way. We now cannot work wit.. 2022. 7. 22. The NZPMC has finally made it to UoA, UC The NZPMC has perhaps formed a significant portion of my university life. It is the first start-up that I built, and every year it gained success, somehow and miraculously. I thank God for leading my way through, and I reflect back on the small things that led to this stage. I will briefly summarise what we achieved in the past 4 years: 2018, after MATHS 153 (Uni course I took in my last year of.. 2022. 7. 16. Finally landed at Atlassian; what are my tips? It has been a long time since the last post. How have you all been? I am glad to say that a lot of good things have been happening across the board this year so far. The first and foremost is probably that I have gotten a graduate Software Engineering (Backend) offer from Atlassian. Consistency really pays off. Blogging, Grokking the Coding interview, referral from friends of years above me, Des.. 2022. 7. 16. Getting your forked repo up to date with main repo note: origin is your forked repo, upstream is the main repo. Sometimes it suffices to just go into your forked repo on github and press that green button (fetch upstream -> fetch and merge). However, if there's a possible conflict in doing so, github will automatically say that you can't do that. What do you do then? You have some commits pushed to your branch on origin so you don't want to rest.. 2022. 3. 13. Setting up typescript MEN (Mongo DB, Express, Node) 1 What's up? I've started working on SOFTENG 701 group project. It's basicallly a 20 human university project that aims to create a web application (well, it can be anything that uses java/js/python but everyone wants to do MERN). It's worth noting how only tiny proportion of the team are familiar with the stack - that means the more you know, the more you can shine really. If you are second/thi.. 2022. 3. 5. 이전 1 다음
