某公司在某条商业街分别开有两家业务上有关联的零售商店，这两家商店的日纯利润变化情况如下表所示：附：线性回归方程 y^=b^x+a^ 中， b^==∑i=1nxiyi−nx¯y¯∑i=1nxi2−nx¯_刷题宝

题干

某公司在某条商业街分别开有两家业务上有关联的零售商店，这两家商店的日纯利润变化情况如下表所示：

附：线性回归方程 y^=b^x+a^ 中， b^==

∑

i

=

1

n

x

i

y

i

−

n

x

¯

y

¯

∑

i

=

1

n

x

i

2

−

n

x

¯

2

∑

i

=

1

n

(

x

i

−

x

¯

)

(

y

i

−

y

¯

)

∑

i

=

1

n

(

x

i

−

x

¯

)

2

， a^=y¯−b^x .

参考数据： ∑i=15(xi−x¯)(yi−y¯)=0.691 ， ∑i=15(xi−x¯)2=0.5 .

上一题下一题 0.0难度选择题更新时间:2013-05-27 02:06:33

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