(discriminatory power) . . , , - . - .
, - . : , , .
.
(r )- j- ; (p1)j , j- 27% ; (0) i. , j- 27% .
r , [-1;1]. 1,00 r , j - e , . .
r , , j- .
r = -1 , , . , r = 0 r < 0 .
r 42 , 100 , . 5.25.
, 6,8, 15,17,31,35 37 . r 4, 20 29
5.25. r 42
| ||||
1 | 67,0 | 48,0 | 87,0 | 0,39 |
2 | 72,0 | 48,0 | 94,0 | 0,45 |
3 | 75,0 | 55,0 | 90,0 | 0,35 |
4 | 25,0 | 16,0 | 32,0 | 0,16 |
5 | 21,0 | 6,5 | 32,0 | 0,26 |
6 | 94,0 | 90,0 | 97,0 | 0,065 |
7 | 82,0 | 74,0 | 94,0 | 0,19 |
8 | 27,0 | 26,0 | 29,0 | 0,032 |
9 | 73,0 | 58,0 | 94,0 | 0,35 |
10 | 66,0 | 55,0 | 87,0 | 0,32 |
11 | 64,0 | 42,0 | 97,0 | 0,55 |
12 | 61,0 | 45,0 | 74,0 | 0,29 |
13 | 34,0 | 9,7 | 42,0 | 0,32 |
14 | 38,0 | 16,0 | 71,0 | 0,55 |
15 | 59,0 | 68,0 | 58,0 | -0,097 |
16 | 85,0 | 65,0 | 97,0 | 0,32 |
17 | 61,0 | 71,0 | 61,0 | -0,097 |
18 | 48,0 | 42,0 | 68,0 | 0,26 |
19 | 88,0 | 71,0 | 94,0 | 0,23 |
20 | 27,0 | 16,0 | 29,0 | 0,13 |
21 | 51,0 | 26,0 | 65,0 | 0,39 |
22 | 35,0 | 16,0 | 42,0 | 0,26 |
23 | 62,0 | 29,0 | 87,0 | 0,58 |
24 | 20,0 | 9,7 | 39,0 | 0,29 |
25 | 41,0 | 23,0 | 42,0 | 0,19 |
26 | 40,0 | 23,0 | 65,0 | 0,42 |
27 | 79,0 | 55,0 | 100,0 | 0,45 |
28 | 37,0 | 6,5 | 61,0 | 0,55 |
29 | 22,0 | 13,0 | 29,0 | 0,16 |
30 | 70,0 | 29,0 | 94,0 | 0,65 |
31 | 26,0 | 32,0 | 19,0 | -0,13 |
32 | 42,0 | 19,0 | 71,0 | 0,52 |
. 5.25
|
|
| ||||
33 | 65,0 | 26,0 | 90,0 | 0,65 |
34 | 30,0 | 13,0 | 42,0 | 0,29 |
35 | 11,0 | 16,0 | 0,0 | -0,16 |
36 | 70,0 | 42,0 | 94,0 | 0,52 |
37 | 12,0 | 9,7 | 16,0 | 0,065 |
38 | 33,0 | 16,0 | 52,0 | 0,35 |
39 | 73,0 | 42,0 | 90,0 | 0,48 |
40 | 46,0 | 29,0 | 58,0 | 0,29 |
41 | 40,0 | 32,0 | 58,0 | 0,26 |
42 | 51,0 | 29,0 | 74,0 | 0,45 |
( ). . , , , - , .
, (rpbis) , . 5.2. . 5.2 rpbis , :
(r pbis)- - - ; (X \) j , j- ; (X1)j , j- ; X ; Sx . .
, (5.62) (5.63), , : , . rpbis . , , . , rpbis . (L. Crocker, J. Algina, P. Kline .) [11,41 .], 0,2, rpbis<0,2 .
rpbis rbis, . , , rbis /-pbis , rbis 0,3. , rbis < 0,3 .
IRT (. 5.3.). j- , :
|
|
( rbis ) j j- .
rbis rbis , [-1, 1 ]. , , rbis .
, |rbis|< 1, Oj (; +). , . 0,5 2,5.
, aj < 1 , . 1 < aj < 2,5.
aj >2,5 , 6 (. 5.3), , ( ) 0 . aj .
, (rmc) j, (rpbis) j, (rbis) j aj- . , . , , , 100200 .
rbis, . rbis. , .
, ,, , . j (j=1, 2,..., ) , rbis. , .. . - , . , , .
. , . , , . = 0,5 , .