title: Python 3 statsmodels Logit ValueError: On entry to DLASCL parameter number 5 had an illegal value
body: <p>Working  through a logistic regression example and encountering some difficulties when approaching the statsmodels portion. I have difficulties in the past with Python 3 and pandas dataframes where the df returns an iterator not a list. I have tried adjusting the same with 'logit' however still receiving a ValueError</p>
  
  <pre><code>import numpy as np
  import pandas as pd
  import os
  import statsmodels.api as sm
  import pylab as pl
  
  df = pd.read_csv('admissions.csv')
  df.head(n=5)
  
  df.columns = ['admit', 'gre', 'gpa', 'prestige']
  dummy_ranks = pd.get_dummies(df['prestige'], prefix='prestige')
  cols_to_keep = ['admit', 'gre', 'gpa']
  data = df[cols_to_keep].join(dummy_ranks.ix[:, 'prestige_2':])
  data['intercept'] = 1.0
  train_cols = data.columns[1:]
  
  
  logit = sm.Logit(data['admit'], data[train_cols])
  
  result = logit.fit()
  </code></pre>
  
  <p>ValueError: On entry to DLASCL parameter number 5 had an illegal value</p>