Reputation: 185
I'm trying to forecast a trend using ARIMA. Unfortunately the output I get is far different from the expected one (behaviour for training and testing data is very similiar) and indicates as if the whole training data set was... useless?
df = pd.read_csv('data.csv')
df.index = pd.DatetimeIndex(df.index).to_period('D')
#data from 1/1/2016 to 31/12/2018
train = df.loc[:'2018-12-31']
test = df.loc['2019-01-01':]
model = auto_arima(train, start_p=1, start_q=1,
max_p=3, max_q=3, m=7,
start_P=0, seasonal=True,
d=1, D=1, trace=True,
error_action='ignore',
suppress_warnings=True,
stepwise=True)
model.aic()
model.fit(train)
ffforecast = model.predict(n_periods=len(test))
ffforecast = pd.DataFrame(fforecast,
index=test.index,
columns=['prediction'])
pd.concat([test, fforecast], axis=1).plot()
pyplot.show()
full code: https://pastebin.com/huer62cM
csv: https://filebin.net/rlvm3hrjetlovd64/newbikes6years.csv?t=nt3slw3y
Upvotes: 0
Views: 136
Reputation: 16172
You're using a bad set of parameters for your model. It looks like you copy/pasted an example from a different data set and it's not working for you.
I would suggest something like:
model = auto_arima(train, error_action='ignore', trace=True, suppress_warnings=True,seasonal=True, maxiter=10, m=7)
Based on the output of this, you can go back and refine the parameters once you read up on them and learn what they do.
Upvotes: 1