postgres time series

1 time series and stochastic processes Random variable sequence Y t:t=0,±1,±2,±3,... is called a stochastic process and is used as a model for observing time series. 2 mean, variance and covariance For the random process Y t:t=0,±1,±2,±3,..., the mean function is defined as follows:Μt =e (Y t), t=0,±1,±2,...That is, μt

From:http://www.cnblogs.com/kemaswill/archive/2013/04/01/2993583.htmlIn the time series, we need to predict the following trend based on the current data of the time series, and the three exponential smoothing (Triple/three Order exponential smoothing,holt-winters) algorithm can predict the

Tags: Layer III ase HTTPS article Zabbix storage thinking dataWThinking about the time series database-csdn.net http://www.csdn.net/article/2015-07-13/2825192Store and process timeseries data ("Time series Databases" chapter III) 1190000002797644 selection criteria for time

First of all, from the point of view of time can be a series of basically divided into 3 categories: 1. Pure random sequence (white noise sequence), this time can stop the analysis, because it is like predicting the next coin which side is as irregular as possible. 2. Stationary non-white noise sequences , whose mean and variance are constants, for such sequences

This learning note is from the "Time series analysis-based on R" written by teacher Wang After the preprocessing of a time series, it is shown that the model has the value of extracting information, then the next model is established to make the prediction. Here are three important models for fitting

DDoS attacks are essentially time-series data, and the data characteristics of t+1 moments are strongly correlated with T-moments, so it is necessary to use HMM or CRF for detection! --and a sentence of the word segmentation algorithm CRF no difference!Note: Traditional DDoS detection is directly based on the IP data sent traffic to identify, through the hardware firewall. Big data scenarios are done for sl

Project questions:When a new user logs on to the mailbox of OWA, it's always time to set the time zone, if it's a test, it doesn't matter.If it is production, you have thousands of people of the enterprise, this certainly is not possible.Workaround:The following workaround is provided by a student that I have not cared about because I do not care about the enterprise it, but this is useful for each student,

interval of those parameters), and the randomness of the individual associated with the specific point of the prediction.For example, a study found that the prediction interval was calculated to include real results 95% of the time only between 71% and 87% of the time to get it (thanks to Hyndman again on his blog easy to get the results). There are many reasons, but the main reason is that uncertainty in

fully dynamic applications through the Web. These applications usually need to be as fast as possible to provide near-real-time components. In this 5-part new series, we will learn how to use reverse Ajax (reverse Ajax) technology to develop event-driven Web applications. In this first article, we need to understand reverse Ajax, polling, streaming, Comet, and long polling ). Learn how to implement differe

value. The default value for the date-time Data Type field column can be set to this "1900-01-01" base date. SQL Server provides a datetime date-time data type that internally uses two 4-byte integers to store the data value. The first 4 bytes stores the number of days before or after the base date (that is, January 1, 1900). The base date is the system reference date. Another 4-byte storage day, expresse

Linux2.6 kernel process scheduling series -- scheduler_tick () function 2. Update the time slice of the real-time process, RT /*** Decrease the time slice counter of the current process and check whether the time slice has been used up. * The operations executed by functions

the basic time slice of the process, which is the time slice length that the system allocates to the process before the process has run out of time. The relationship between the static priority and the base time slice is determined by the following formula:As you can see, the higher the static priority (the smaller th

[Best Practices Series] PHP date, time and time zone Processing API and component processing date and time need to consider a lot of things, such as the date format, time zone, leap year and days of different months, self-processing is too error-prone. we should use the Date

UTC time: System UTC time = RTC time, local time = RTC Time + 8 hoursIn fact, it is possible to set any kind. However, notice that the Windows system defaults to the RTC time as local time