title: Python Error :'numpy.float64' object is not callable
body: <p>I have written a code in python to generate a sequence of ARIMA model's and determine their AIC values to compare them.The code is as below,</p>
  
  <pre><code>p=0
  q=0
  d=0
  
  for p in range(5):
      for d in range(1):
          for q in range(4):
              arima_mod=sm.tsa.ARIMA(df,(p,d,q)).fit()
              print(arima_mod.params)
              print arima_mod.aic()
  </code></pre>
  
  <p>I am getting a error message as below,</p>
  
  <pre><code>TypeError                                 Traceback (most recent call last)
  &lt;ipython-input-60-b662b0c42796&gt; in &lt;module&gt;()
        8             arima_mod=sm.tsa.ARIMA(df,(p,d,q)).fit()
        9             print(arima_mod.params)
  ---&gt; 10             print arima_mod.aic()
          global arima_mod.aic = 1262.2449736558815
       11 
  
  **TypeError: 'numpy.float64' object is not callable**
  </code></pre>