Programmer Think

1. Reptile target It is generally believed that Python crawlers are powerful, but Python has some difficulties in solving dynamic loading or landing websites. Compared with some ordinary crawlers, using R language will be more convenient. with https://www.thepaper.cn/ For example, the httr package commonly used in dynamic web pages is mainly ...

It's interesting to do meta analysis recently. Once you master these skills, you don't have to worry about publishing articles in the future. Meta analysis is also one of the very important methods in medicine. This issue analyzes several classic graphics based on existing data, including forest, vulnerability, radial, labe And Q-Q normal. 01 ...

Spatial object data visualization In the process of spatial data processing and analysis, a main feature is to visualize spatial objects and make exquisite maps. This section introduces the method of spatial visualization. Load packages and data Spatial data visualization #example library(maptools) require(rgeos) LN.bou <- readSh ...

catalogue Using random forest to evaluate the transaction price of second-hand cars Random forest principle previously on data sources Data preprocessing Data completion and variable deletion Data outlier handling Establishment and optimization of Stochastic Forest Model Tree selection Selection of independent variables Adjustment ...

catalogue 1, Definition of RFM analysis: II. Assumptions of RFM analysis 3, Steps of RFM analysis 4, RMF analysis example 4.1 data preparation 4.2 calculation of R/F/M 4.3 score and assign R, F and M in groups 4.4 calculate the comprehensive score of RFM 4.5 customer classification Note: personal study notes - who says rookies can ...

Chapter 2 linear regression 2.1 simple linear regression The ISLR2 library contains the Boston dataset, which records medv (median house value) for 506 census districts in Boston. We will use 12 predictive variables, such as rmvar (average number of rooms per household), age (average house age), and lstat (percentage of households with low so ...

0618 15:00 Story: eight green brothers of Slot Machine https://rstudio-education.github.io/hopr/programs.html People who have not experienced Vegas will have a little trouble understanding the story. Like myself. Three different icon combinations will be generated when a machine plays once. If the icon combination meets the winning ...

apply series functions Hello, everyone. I want to be a big dinosaur 🦖 My birthday letter Xiaobai. Praise first and then see. Form a habit. Little friends who haven't paid attention don't get lost. Today, let's talk about the apply series functions in R language preface In R language, apply series functions can apply function operati ...

R language is a mathematical programming language designed for mathematical researchers. It is mainly used for statistical analysis, drawing and data mining. R language is a language for interpretation and operation (different from the compilation and operation of C language). Its execution speed is much slower than C language, which is not con ...

1, Data description agpop data file introduction: the U.S. government conducts a general survey on agriculture every five years and collects relevant data on all farms in 50 states. The data file contains a total of 3041 U.S. county-level farms or farm data equivalent to county-level farms. There are 4 regions / rnum, 50 states / snum, and 304 ...