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Refers to the AutoRegressive Integrated Moving Average model used in time series modeling both for data description and for forecasting. This model generalizes the ARMA model by including a term for differencing, which is useful for removing trends and handling some types of non-stationarity.
2
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3
answers
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ARIMA model with flat forecasts
=-385.31
AIC=774.62 AICc=775.19 BIC=776.98
& I get flat forecasts.I have tried using drift but that only helps when forecasting for 2016 & flattens 2017 onward. … Is there something that can be done to overcome this.I have also tried the similar exercise in SAS using proc UCM & that seems to generate forecasts better than the auto.arima.
Can someone help out? …
2
votes
1
answer
1k
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Flat forecast of trended time series data in R
I assumed i will get a forecast where there is an upward trend as there is trend historically along with some variations but what i got is flat forecast. … <- forecast(model,12)
plot(forecasts)
If i go with the seasonal plot of both historical data along with 2019 forecast these is how it looks
The series seems to be forecastable and therefore shouldn't …
0
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0
answers
2k
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Why is my AUTO ARIMA giving flat forecast
I have a AUTO ARIMA fitted on weekly. It gives a forecast as flat line as seen below
I tried adding seasonality and stuff, but still the forecast is a flat line. …
0
votes
1
answer
2k
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Flat Forecast from ARIMA and SARIMA [duplicate]
ARIMA/SARIMA models are able to follow the variation in training data. But it generates nearly flat prediction for the test period. … fit.test <- model_arima %>% forecast(h=length(ts_test))
I am unable to understand what can be the reason for flat predictions from ARIMA/SARIMA models and how can I fix it? …
1
vote
1
answer
4k
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Why am I getting flat time series forecasts from most of the techniques?
models: Holt Winters smoothing, TBATS Smoothing, ARIMA, and AR Neural Nets with the following functions in R, using the "forecast" package: HoltWinters, tbats, auto.arima, nnetar
I forecasted 36 periods … The following results:
My question is why does the HoltWinters seem to be the only meaningful forecast. I have enough data that getting flat lines for all the other forecasts seems odd. …
1
vote
1
answer
970
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SAS: Flat line forecast ARIMA model?
I'm trying to forecast a large dataset using ARIMA (The data does not have seasonality), I ended up getting an ARIMA(2,1,2) model where the log of volume was taken due to increase in variance over … model ;
proc arima data=intel_stock;
identify var= logvolume(1);
estimate p = 2 q = 2 ;
forecast lead=60 interval=month id=Date out=forecast;
run;
* Merge forecast and volume into the same dataset and …
2
votes
1
answer
5k
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Getting flat prediction with ARIMA model in Python
I am using an arima model to forecast sales of a given product in python, using statsmodels.tsa.arima.model.ARIMA Sales are daily, with a history of 2019 until today. … The model is adjusting correctly to the past, however when performing the forecast, it returns a flat line, as in the image shown. …
6
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Accepted
Choosing Between Intercept-Only and AR-NN Models: Justified to not use the model with the lo...
Of course, it is unintuitive that a flat, non-varying, forecasts "explains variation" better than a variable NN forecast. … It is extremely common for flat historical mean forecasts to outperform more complex ones, whether ARIMA or ML-based: Is it unusual for the MEAN to outperform ARIMA? …
2
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auto.arima is showing same forecasted values in R studio
Thus, a flat forecast is exactly what an ARIMA(0,1,0) model does. … Fitting an exponential smoothing model, incidentally, also yields a flat forecast:
plot(forecast(ets(Russia_ShareofGDP_TS),h=16))
Now, I often argue that a flat forecast my well be the best forecast there …
1
vote
1
answer
400
views
How to decide p P q Q of ARIMA through ACF and PACF?
(Preface)
My problem is that when I do the time series forecast with auto.arima(), it gives me a ARIMA(1,1,1) model which generate a flat forecast line as the below figure. … (forecast next quater)
model = auto.arima(data_ts)
autoplot(forecast(model,13))
However, I assign D = 1 in auto.arima() function according to suggestion from ARIMA forecast straight line? …
5
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0
answers
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Constant in arima model whether to include or exclude?
I have a very basic question on including constant in Arima models. I'll illustrate this by an example. … Arima
with drift or SES with drift.
When I do not include a constant, I get a flat forecast which is reasonable for the series at hand. …
2
votes
1
answer
234
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ARIMA Modeling on specific time series
ARIMA(1,0,0) with non-zero mean : 98.46206
ARIMA(0,0,1) with non-zero mean : 98.42101
ARIMA(0,0,0) with zero mean : 104.5138
ARIMA(1,0,1) with non-zero mean : 100.3878
there is ARIMA(0,0,1) the … best second model,
but when using at forecasting, White Noise will give a flat forecasting (because its definition is not suitable for forecasting as i known so far), so is it a good way to implement …
0
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ARIMA model with flat forecasts
How do you expect to get anything but a flat forecast? … more data would be better, especially if you want to train this ARIMA model. …
2
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4
answers
1k
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ARIMA forecasting life expectancy
The ARIMA(1,1,2) is the best model with the lowest AICc. I'm in trouble with the point forecast where the straight line is flat. … library(forecast)
AA<-Alberta$Male
AA1<-ts(AA,start=1921,end=2009,frequency=1)
A2<-diff(AA1,1)
fit1<-arima(A2, order=c(1,1,0))
fit2 <-arima(A2, order=c(1,1,1))
fit3<-arima(A2, order=c(1,1,2))
fit4<-arima …
2
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ARIMA Forecast , Future prediction growth coming in constant with same growth rate
Your question is extremely similar to many questions about "flat forecasts" from ARIMA models. Please take a look through those earlier threads. … In your case, the ARIMA forecast converges quickly to the linear trend.
Note also that ARIMA - and any other method as well - attempts to separate the signal from the noise. …