model.conf_int()
>>
array([[-26.12390808,   3.75824557],
       [  2.10177067,   4.76517923],
       [ -4.15562353,  -1.75984506],
       [  0.81415711,   3.20029178],
       [  2.15244579,   4.42718347],
       [ -3.49724847,  -0.3241592 ]])