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### ARIMA model identification [duplicate]

Having a bit of difficulty identifying the appropriate ARIMA model by looking at ACF/PACFs. I know that AR(1) models, the ACF has a geometric progression from its highest value at lag 1 and the PACF ...
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### Help Identifying Time Series Model From ACF and PACF graphs [duplicate]

I have a dataset of the popularity of a certain word on the internet, and they are weekly counts from 2010-09-05 to 2015-09-27 and has an upward trend. I'm having a hard time identifying the model ...
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### Time series analysis ACF-PACF [duplicate]

I have run a ITS analysis on my dataset but I am unable to know which ARMA process to use. Please help understand how to select the ARMA process. I'm stuck.
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### Under what circumstances is an MA process or AR process appropriate?

I understand that if a process depends on previous values of itself, then it is an AR process. If it depends on previous errors, then it is an MA process. When would one of either of these two ...
23k views

### How to interpret ACF and PACF plots

I just want to check that I am interpreting the ACF and PACF plots correctly: The data corresponds to the errors generated between the actual data points and the estimates generated using an AR(1) ...
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### ACF and PACF plot analysis

I am new to ARIMA, and I am trying to understand these lag plots. Are the following ACF and PACF suggesting that the lag of my time series is 4? If I am wrong, please help me understand these plots.
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### Can First Differencing Cause Negative Serial Correlation

Ex. series, say stock prices 103 101 102 150 101 102 100 First differenced 2 1 48 -49 1 -2 Notice you could guess a very large negative number following the very large positive in the first ...
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### When to choose which model for time series?

What are the applications of AR and MA model? To put my question exactly, when to use AR model and when to use MA model(for example, like when it is seasonal or when there is a trend, etc). In other ...