R. . Braskin & Associates " American Express" (The American Express National Travel Forecast), OmniTel. 1030 (525 , 505 ). , , , , . , 25 49 , , , , . (65 ) ( ). 18 34 . , . , , , . , , [23].
(. . 11.2). , , . , , . . -, . , . , . -, , . ( , , , .) , , .
. , , . , , . . , .
|
|
. , . , , 50 , , 125 . , 125 . . SRS . .
(cluster sampling) , (clusters). , SRS, . , . , . , . . 11.3, SRS , (PPS). , ( ) , .