问题 多项选择题

关于决定系数,下列说法正确的有()。

A.决定系数的取值在0到1之间

B.决定系数越接近于0,说明模型的拟合效果就越好

C.决定系数为1说明回归直线可以解释因变量的所有变化

D.决定系数为0说明回归直线无法解释因变量的变化

E.决定系数的取值大体上说明了回归模型所能解释的因变量变化占因变量总变化的比例

答案

参考答案:A, C, D, E

解析:本题考查决定系数的相关内容。选项B说法有误,决定系数越接近于1,说明模型的拟合效果就越好。

完形填空
完形填空。
     I remember that when I was in my teens,I used to refuse  to  follow the many"dos"and"don'ts"of my
parents.For example,when I planned to sleep with my pet dog, they immediately said ,"   1  "because
they thought it was dangerous.This was just an example of the things I thought my parents were    2  
about.        
     Today,however,I am the father of a boy aged 15,and I find that I too,am pressuring my son with a
lot of    3    that are hard for him.
     The   4    day,I noticed that my son was wearing  giant  pants  that could    5   three teenagers.  No
one should wear them.I commanded  him  to take them off at once . Usually,he 6   me, but this  time
he put his foot down."What's  wrong with giant pants ? 7   classmates  wear them. And I don't think
you have the right to ask me to remove them,  8  you are my father !" said he.I    9   realized that we
are now living in a society with more freedom,and that my son's strong will on wearing giant pants was
just an  10  of the generation gap(代沟) between us.Therefore,   I gave in and now he is still wearing
giant pants.
( )1. A.Stay up    
( )2. A.unreasonable
( )3. A.jobs    
( )4. A.another    
( )5. A.put    
( )6. A.allowed    
( )7. A.All my    
( )8. A.after all  
( )9.     A. possibly    
( )10.   A.instance  
B.Come along  
B.unforgettable
B.rules    
B.other    
B.wear    
B.annoy    
B.My all    
B.only if    
B.suddenly    
B.challenge    
C.No way
C.unbelievable
C.notes  
C.others  
C.stay    
C.argues  
C.All the my
C.even though
C.especially  
C.resolution  
D.No problem    
D.uncomfortable
D.habits        
D.other's      
D.hold          
D.obeys        
D.My all the    
D.as for        
D.extremely    
D.assessment    
单项选择题