问题 多项选择题

为分析某市城镇居民1995年~2003年人均可支配收入和人均消费性支出之间的关系,取得如下统计资料:

某市1995年~2003年有关统计资料

单位:元

并已求得:

请根据以上资料进行计算和分析判断,从备选答案中选出正确答案。

根据资料计算的判定系数R2=0.9973,这表明()。

A.某市城镇居民1995年—2003年人均消费性支出的变化有99.73%是由人均可支配收入决定的

B.在Y的总变差中,有99.73%可以由解释变量X做出解释

C.在Y的总变差中,有0.27%可以由解释变量X做出解释

D.回归方程对样本观测值的拟合程度良好

答案

参考答案:A, B, D

解析:

判定系数是指回归平方和占总体平方和的比例,它是度量拟合程度的一个估计量,反映了因变量Y的偏差中被估计的回归方程所解释的比例。R2=0.9973表明在Y的总变差中,有99.73%可以由解释变量X(或回归方程)做出解释,回归方程对样本观测值的拟合程度良好。也就是说镇居民1995年-2003年人均消费性支出的变化有99.73%是由人均可支配收入决定的。

完形填空
An old friend from the US whom I was looking forward to staying with , telephoned from the airport to tell me that he had arrived . I was still at the    at that time , but I had got everything ready for his arrival . After letting him know where my house was,I told him that I had left the     under the door--mat(门垫).    I was likely to be home rather late , I told him to go into the     and help himself to food and drink .
Two hours later my friend    me from the house . At the moment , he said , he was listening to some of my records after having just had a truly wonderful    . He had found a cooker and     two eggs and had helped himself to some cold chicken from the ice box . Now , he said , he was drinking a glass of orange juice and he hoped I would    him . When I asked him if he had reached the house without difficulty , he answered , “I was not able to find the key ,    luckily the living-room windows just by the apple tree were left open and you know what I could do .”
I listened to all this in    .In front of my living-room there was no apple tree at all .
小题1:
A.1iving—room B.office C.airport D.house
小题2:
A.addressB.telephone number C.key D.traveling plan
小题3:
A.As B.When C.If D.Though
小题4:
A.store B.restaurant C.fridge D.kitchen
小题5:
A.invited B.asked C.answered D.telephoned
小题6:
A.mealB.rest C.time D.picnic
小题7:
A.got B.broke C.fried D.bought
小题8:
A.visit B.join C.thank D.remember
小题9:
A.but B.so C.or D.and
小题10:
A.interest B.angerC.surprise D.Excitement
实验题