title: 'DataFrame' object has no attribute 'market_value' ​
body: <p>I am trying to plot the ACF of the datasets but getting an error saying &quot; AttributeError: 'DataFrame' object has no attribute 'market_value' .&quot;</p>
  <pre><code>import pandas as pd
  import numpy as np
  import matplotlib.pyplot as plt
  import statsmodels.graphics.tsaplots as sgt
  from statsmodels.tsa.arima_model import ARMA
  from scipy.stats.distributions import chi2
  import seaborn as sns 
  sns.set()
  
  df_comp = pd.read_csv(&quot;Index2018.csv&quot;)
  df_comp.date = pd.to_datetime(df_comp.date,dayfirst = True) 
  df_comp.set_index(&quot;date&quot;,inplace = True)
  df_comp['market value'] = df_comp.ftse
  
  size = int(len(df_comp)*0.8)
  df, df_test = df_comp.iloc[:size],df_comp.iloc[size:]
  sgt.plot_acf(df.market_value, zero = False, lags = 40) 
  plt.title(&quot;PACF&quot;, size = 24)
  plt.show()
  </code></pre>