• ## Why does Pi appear in the equation of the normal distribution?

Time：2022-8-10

This article will explain how the bell curve is formed, and why π appears in the formula for a curve that seems to have nothing to do with it. While flipping through an old statistics textbook recently I came across a familiar equation for the normal distribution: Anyone who has taken a statistics course in […]

• ## R language nonlinear regression NLS exploratory analysis of river periodic flow data and rating curve, flow prediction visualization

Time：2022-7-13

Original link:http://tecdat.cn/?p=24761  This document formulates the rating curve and flow prediction of the river through some exploratory data analysis. The purpose is to create and update the rating curve using (1) the instantaneous flow measured during the periodic deployment of the bottom installation unit and (2) the instantaneous depth measurement from the water level data […]

• ## Summary of some indicators for evaluating and selecting the best learning model

Time：2022-7-5

When evaluating the model, although accuracy is an important indicator for model evaluation and application model adjustment in the training stage, it is not the best indicator for model evaluation. We can use several evaluation indicators to evaluate our model. Because the data we use to build most models is unbalanced, and the model may […]

• ## How to merge multiple survival analysis curve pictures

Time：2022-6-23

survminerPackagedggsurvplot()The function can draw a good-looking survival analysis curve, and can also use the faceted method to draw multiple groups of pictures (for the tutorial, please refer to my previous advice to the student letter assistant“Lingyun 34” multiple overall survival plots (2), thoughggsurvplot()The syntax of is based on ggplot2 (in fact, it should be ggpubr), […]

• ## Android custom view (12) – draw a real-time electrocardiograph

Time：2022-6-23

summary This time I will talk about the drawing of ECG, which is also used in the project. ECG is inherited from view. To sum up, it mainly includes the following contents:Real time display of ambulatory ECG data, ECG waveform left-right sliding, inertial sliding and waveform x-axis and y-axis double finger sliding and scaling.Let’s take […]

• ## Whether qPCR is effective or not, these six elements should be known ~

Time：2022-6-14

Real time fluorescent quantitative PCR: add fluorescent groups (probes or dyes) to the PCR reaction system, use the accumulation of fluorescent signals to monitor the whole PCR reaction process in real time, and finally conduct absolute or relative quantitative analysis on the initial template through CQ or CT value and standard curve. The effect of […]

• ## ROC curve

Time：2022-6-5

brief introduction Receiver operating characteristic curve (ROC curve for short) is a visual tool to compare the two classification models. effect 1. the ability to identify categories when any limit value can be easily found out 2. select the best diagnostic limit value. The closer the ROC curve is to the upper left corner, the […]

• ## R language | Cox model calibration curve drawing

Time：2022-5-30

Transferred from personal wechatGongzong No. [Yi Xue statistics]Statistical learning notes for:Drawing calibration curve of Cox model with R language Research background This is the second article about Cox model. The last article shared how to use lasso regression to screen variables and draw nomograms of the screened variables. This chapter shared how to draw calibration […]

• ## Objc implementation sharing of sccatwaitinghud

Time：2022-5-15

The original is published inAnimatious animation open source group Welcome tomicro-blogandgithubPay attention to us introduce This idea actually comes from a group of GIF pictures forwarded by @ draw slag program ape mmoaay on Weibo and sent by Aite meWhen I see the diagram, I first roughly distinguish the structure and hierarchy of the diagramWhen […]

• ## Understanding Schnorr Signature Algorithm

Time：2022-4-12

In the previous chapter, we talked about that the aggregate signature used in wisdomchain is the signature aggregation of their respective keys generated by all parties using Schnorr Signature. Today, let’s learn about the past and present life of Schnorr Signature Algorithm. Schnorr Signature Algorithm was first proposed by German Cryptologist Claus Schnorr in 2008. […]

• ## [QT] custom component_ Dynamic curve

Time：2022-4-4

Component collection Warehouse characteristic Y-axis range, label format and number of ticks can be set X-axis time span, time format and number of ticks can be set It can display any number of curves, set the corresponding curve color and whether the numerical points are displayed Curve update interval can be set Optionally hide curves […]

• ## In order to let her learn to draw – stay up late and realize a drawing board with canvas

Time：2022-4-2

preface Hello everyone, I’m fly. Canvas is really a powerful thing. I can’t extricate myself from indulging in this every day. I can play games and deal with pictures. I’ll share an article later. Canvas realizes two pictures to find different functions. Does it sound very interesting and a bit like a gameLooking for your […]