Model Factors Elementary Middle High
β t β t β t
1 Demographic Gender(M=0)
School Year
Local Community
Economic Status		 -.137

-.096
-.159		    -5.43***

   -3.79***
   -6.30***		  .153
 .129

-.112		     5.91***
    4.98***

   -4.28***		  .188


-.105		    6.85***


  -3.80***
2 Usage Time  .395   16.87***  .326   12.78***  .190     6.96***
3 Friends Number
Quality
-.264
-11.65***		  .057
-.319		     2.43*
-13.72***
-.306
-11.77***
4 Adults Father
Mother
S. Teacher
I. Teacher		 -.107
-.075		    -4.15***
   -3.09**		 -.128



    -4.46***



 -.138


-.084		   -4.36***


  -3.13**