• [front end algorithm] 1046. The weight of the last stone, violent solution


    There is a pile of stones, and the weight of each stone is a positive integer. Each round, choose two of the heaviest stones, and then smash them together. Suppose the weight of the stone is x and Y respectively, and x < = y. The possible results of comminution are as follows: If x […]

  • Face recognition based on BP neural network


    1、 Threshold logic unit Threshold logic unit (Tlu), which can input a group of weighted coefficient quantity, sum them, if the sum reaches or exceeds a certain threshold, output a quantity. For example, the inputs are A1, A2,…, an and the weights W1, W2,  …, wn。 Then there is the sum of AI x wi […]

  • Using class weight to improve class imbalance


    AuthorCompile VKSource: analytics vidhya summary Learn how class weight optimization works and how to use sklearn to implement the same method in logistic regression or any other algorithm Learn how to overcome the problem of unbalanced class data by modifying the class weight without using any sampling method introduce The classification problem in machine learning […]

  • Re learning front end CSS (1) introduction to CSS


    This series of articles is mainly about CSS content, including: CSS selector API, CSS weight, layout, sticky layout, BFC and so on. If there is anything wrong with my writing, please give me your advice. If you think there is anything important that I haven’t mentioned, please let me know. Thank you. How to apply […]

  • What’s the difference between @ link and @ import? what’s the diffrence between link and @import ?


    What’s the diffrence between link and @import ? the link belongs to the tags of xhtml, but @import is provided by css the link will loading when the web page is loaded, but css that referenced by @import will wait until the web page is loaded. the @import just can be recognized in ie5 and […]

  • Stata: RA: Regression adjustment, IPW: inverse probability weighting, ipwra, aipw


    Link to the original text:http://tecdat.cn/?p=10148 Today’s topic is the therapeutic effect in Stata. The therapeutic effect estimator estimates the causal relationship between treatment and outcome based on the observed data. We will discuss four therapeutic effect estimators: RA: Regression adjustment IPW: inverse probability weighting Ipwra: inverse probability weighting with regression adjustment Aipw: enhanced inverse probability […]

  • Database transaction back test series 3: multi factor alpha strategy optimal factor weight


    In the second part of this series(Multi factor alpha strategy backtesting)In this paper, we test the four quantitative factors of the U.S. stock market. Here, we’ll use the built-inquadprogFunction to optimize the mean variance of each factor weight to determine the best factor weight. After the script provided in the second part of this series […]

  • Memos for pandas data visualization


    By Rashida nasrin suckyCompile VKSource: towards Data Science We use Python’s pandas library mainly for data operation in data analysis, but we can also use pandas for data visualization. You don’t even need to import the Matplotlib library for this. Pandas itself can use Matplotlib on the back end and visualize it for you. It […]

  • What does neural network deal with


    We often hear that neural networks are used in image recognition or image generation. It is often said that neural network is a technology of big data classification, using the original data for model training, until generating a reliable classifier. The basic structure of this model is a neural network composed of convolution calculation of […]

  • Leetcode 990. Satisfiability of equation | Python


    990. Satisfiability of equation Title Source: leetcode https://leetcode-cn.com/problems/satisfiability-of-equality-equations subject Given an array composed of string equations representing the relationship between variables, the length of each string equation [i] is 4 and takes one of two different forms: “a = = B” or “a! = B”. In this case, a and B are lowercase letters (not […]

  • Regularization in deep learning (1)


    This article starts with the official account number: RAIS, click direct attention. preface This series of articles are reading notes of deep learning, which can be read together with the original book for better effect. In this paper, we talk about regularization in deep learning. Regularization in deep learning Generally speaking, what deep learning needs […]

  • Jpg learning notes 2 (with complete code)


    We have got the data that need to compress RGB from BMP. We need to transform the original data from RGB domain to YCbCr domain, and then down sample the YCbCr data. For students who don’t need to read the article, the source code is given here directly.https://github.com/Cheemion/JPEG_COMPRESS Image reference “compressed image file formats, JPEG, […]