Oracle PL/SQL Tutorial/Linear Regression Functions/STATS F TEST
Содержание
- 1 For degrees of freedom: STATS_F_TEST(expr1, expr2, "DF_NUM")
- 2 For significance level of one-sided test: STATS_F_TEST(expr1, expr2, "ONE_SIDED_SIG")
- 3 For significance level of two-sided test: STATS_F_TEST(expr1, expr2, "TWO_SIDED_SIG")
- 4 For the test statistic value: STATS_F_TEST(expr1, expr2, "STATISTIC")
- 5 STATS_F_TEST(expr1, expr2, "DF_DEN")
For degrees of freedom: STATS_F_TEST(expr1, expr2, "DF_NUM")
<source lang="sql">
SQL> SQL> SQL> -- create demo table SQL> create table myTable(
2 id NUMBER(2), 3 value NUMBER(6,2) 4 ) 5 /
Table created. SQL> SQL> -- prepare data SQL> insert into myTable(ID, value)values (1,9); 1 row created. SQL> insert into myTable(ID, value)values (2,2.11); 1 row created. SQL> insert into myTable(ID, value)values (3,3.44); 1 row created. SQL> insert into myTable(ID, value)values (4,-4.21); 1 row created. SQL> insert into myTable(ID, value)values (5,10); 1 row created. SQL> insert into myTable(ID, value)values (6,3); 1 row created. SQL> insert into myTable(ID, value)values (7,-5.88); 1 row created. SQL> insert into myTable(ID, value)values (8,123.45); 1 row created. SQL> insert into myTable(ID, value)values (9,98.23); 1 row created. SQL> insert into myTable(ID, value)values (10,938.23); 1 row created. SQL> insert into myTable(ID, value)values (11,984.23); 1 row created. SQL> insert into myTable(ID, value)values (12,198.23); 1 row created. SQL> insert into myTable(ID, value)values (13,928.87); 1 row created. SQL> insert into myTable(ID, value)values (14,25.37); 1 row created. SQL> insert into myTable(ID, value)values (15,918.3); 1 row created. SQL> insert into myTable(ID, value)values (16,9.23); 1 row created. SQL> insert into myTable(ID, value)values (17,8.23); 1 row created. SQL> SQL> select * from myTable
2 / ID VALUE
----------
1 9 2 2.11 3 3.44 4 -4.21 5 10 6 3 7 -5.88 8 123.45 9 98.23 10 938.23 11 984.23 ID VALUE
----------
12 198.23 13 928.87 14 25.37 15 918.3 16 9.23 17 8.23
17 rows selected. SQL> SQL> SQL> SELECT STATS_F_TEST(1.2, value, "DF_NUM") FROM myTable; STATS_F_TEST(1.2,VALUE,"DF_NUM")
SQL> SQL> SQL> -- clean the table SQL> drop table myTable
2 /
Table dropped.</source>
For significance level of one-sided test: STATS_F_TEST(expr1, expr2, "ONE_SIDED_SIG")
<source lang="sql">
SQL> SQL> SQL> -- create demo table SQL> create table myTable(
2 id NUMBER(2), 3 value NUMBER(6,2) 4 ) 5 /
Table created. SQL> SQL> -- prepare data SQL> insert into myTable(ID, value)values (1,9); 1 row created. SQL> insert into myTable(ID, value)values (2,2.11); 1 row created. SQL> insert into myTable(ID, value)values (3,3.44); 1 row created. SQL> insert into myTable(ID, value)values (4,-4.21); 1 row created. SQL> insert into myTable(ID, value)values (5,10); 1 row created. SQL> insert into myTable(ID, value)values (6,3); 1 row created. SQL> insert into myTable(ID, value)values (7,-5.88); 1 row created. SQL> insert into myTable(ID, value)values (8,123.45); 1 row created. SQL> insert into myTable(ID, value)values (9,98.23); 1 row created. SQL> insert into myTable(ID, value)values (10,938.23); 1 row created. SQL> insert into myTable(ID, value)values (11,984.23); 1 row created. SQL> insert into myTable(ID, value)values (12,198.23); 1 row created. SQL> insert into myTable(ID, value)values (13,928.87); 1 row created. SQL> insert into myTable(ID, value)values (14,25.37); 1 row created. SQL> insert into myTable(ID, value)values (15,918.3); 1 row created. SQL> insert into myTable(ID, value)values (16,9.23); 1 row created. SQL> insert into myTable(ID, value)values (17,8.23); 1 row created. SQL> SQL> select * from myTable
2 / ID VALUE
----------
1 9 2 2.11 3 3.44 4 -4.21 5 10 6 3 7 -5.88 8 123.45 9 98.23 10 938.23 11 984.23 ID VALUE
----------
12 198.23 13 928.87 14 25.37 15 918.3 16 9.23 17 8.23
17 rows selected. SQL> SQL> SQL> SELECT STATS_F_TEST(1.2, value, "ONE_SIDED_SIG") FROM myTable; STATS_F_TEST(1.2,VALUE,"ONE_SIDED_SIG")
SQL> SQL> SQL> -- clean the table SQL> drop table myTable
2 /
Table dropped.</source>
For significance level of two-sided test: STATS_F_TEST(expr1, expr2, "TWO_SIDED_SIG")
<source lang="sql">
SQL> SQL> -- create demo table SQL> create table myTable(
2 id NUMBER(2), 3 value NUMBER(6,2) 4 ) 5 /
Table created. SQL> SQL> -- prepare data SQL> insert into myTable(ID, value)values (1,9); 1 row created. SQL> insert into myTable(ID, value)values (2,2.11); 1 row created. SQL> insert into myTable(ID, value)values (3,3.44); 1 row created. SQL> insert into myTable(ID, value)values (4,-4.21); 1 row created. SQL> insert into myTable(ID, value)values (5,10); 1 row created. SQL> insert into myTable(ID, value)values (6,3); 1 row created. SQL> insert into myTable(ID, value)values (7,-5.88); 1 row created. SQL> insert into myTable(ID, value)values (8,123.45); 1 row created. SQL> insert into myTable(ID, value)values (9,98.23); 1 row created. SQL> insert into myTable(ID, value)values (10,938.23); 1 row created. SQL> insert into myTable(ID, value)values (11,984.23); 1 row created. SQL> insert into myTable(ID, value)values (12,198.23); 1 row created. SQL> insert into myTable(ID, value)values (13,928.87); 1 row created. SQL> insert into myTable(ID, value)values (14,25.37); 1 row created. SQL> insert into myTable(ID, value)values (15,918.3); 1 row created. SQL> insert into myTable(ID, value)values (16,9.23); 1 row created. SQL> insert into myTable(ID, value)values (17,8.23); 1 row created. SQL> SQL> select * from myTable
2 / ID VALUE
----------
1 9 2 2.11 3 3.44 4 -4.21 5 10 6 3 7 -5.88 8 123.45 9 98.23 10 938.23 11 984.23 ID VALUE
----------
12 198.23 13 928.87 14 25.37 15 918.3 16 9.23 17 8.23
17 rows selected. SQL> SQL> SQL> SELECT STATS_F_TEST(1.2, value, "TWO_SIDED_SIG") FROM myTable; STATS_F_TEST(1.2,VALUE,"TWO_SIDED_SIG")
SQL> SQL> SQL> -- clean the table SQL> drop table myTable
2 /
Table dropped.</source>
For the test statistic value: STATS_F_TEST(expr1, expr2, "STATISTIC")
This function tests the equality of two population variances.
The resulting f value is the ratio of one sample variance to the other sample variance.
Values very different from 1 usually indicate significant differences between the two variances.
<source lang="sql">
SQL> -- create demo table SQL> create table myTable(
2 id NUMBER(2), 3 value NUMBER(6,2) 4 ) 5 /
Table created. SQL> SQL> -- prepare data SQL> insert into myTable(ID, value)values (1,9); 1 row created. SQL> insert into myTable(ID, value)values (2,2.11); 1 row created. SQL> insert into myTable(ID, value)values (3,3.44); 1 row created. SQL> insert into myTable(ID, value)values (4,-4.21); 1 row created. SQL> insert into myTable(ID, value)values (5,10); 1 row created. SQL> insert into myTable(ID, value)values (6,3); 1 row created. SQL> insert into myTable(ID, value)values (7,-5.88); 1 row created. SQL> insert into myTable(ID, value)values (8,123.45); 1 row created. SQL> insert into myTable(ID, value)values (9,98.23); 1 row created. SQL> insert into myTable(ID, value)values (10,938.23); 1 row created. SQL> insert into myTable(ID, value)values (11,984.23); 1 row created. SQL> insert into myTable(ID, value)values (12,198.23); 1 row created. SQL> insert into myTable(ID, value)values (13,928.87); 1 row created. SQL> insert into myTable(ID, value)values (14,25.37); 1 row created. SQL> insert into myTable(ID, value)values (15,918.3); 1 row created. SQL> insert into myTable(ID, value)values (16,9.23); 1 row created. SQL> insert into myTable(ID, value)values (17,8.23); 1 row created. SQL> SQL> select * from myTable
2 / ID VALUE
----------
1 9 2 2.11 3 3.44 4 -4.21 5 10 6 3 7 -5.88 8 123.45 9 98.23 10 938.23 11 984.23 ID VALUE
----------
12 198.23 13 928.87 14 25.37 15 918.3 16 9.23 17 8.23
17 rows selected. SQL> SQL> SQL> SELECT STATS_F_TEST(1.2, value, "STATISTIC") FROM myTable; STATS_F_TEST(1.2,VALUE,"STATISTIC")
SQL> SQL> SQL> -- clean the table SQL> drop table myTable
2 /
Table dropped.</source>
STATS_F_TEST(expr1, expr2, "DF_DEN")
<source lang="sql">
SQL> SQL> SQL> -- create demo table SQL> create table myTable(
2 id NUMBER(2), 3 value NUMBER(6,2) 4 ) 5 /
Table created. SQL> SQL> -- prepare data SQL> insert into myTable(ID, value)values (1,9); 1 row created. SQL> insert into myTable(ID, value)values (2,2.11); 1 row created. SQL> insert into myTable(ID, value)values (3,3.44); 1 row created. SQL> insert into myTable(ID, value)values (4,-4.21); 1 row created. SQL> insert into myTable(ID, value)values (5,10); 1 row created. SQL> insert into myTable(ID, value)values (6,3); 1 row created. SQL> insert into myTable(ID, value)values (7,-5.88); 1 row created. SQL> insert into myTable(ID, value)values (8,123.45); 1 row created. SQL> insert into myTable(ID, value)values (9,98.23); 1 row created. SQL> insert into myTable(ID, value)values (10,938.23); 1 row created. SQL> insert into myTable(ID, value)values (11,984.23); 1 row created. SQL> insert into myTable(ID, value)values (12,198.23); 1 row created. SQL> insert into myTable(ID, value)values (13,928.87); 1 row created. SQL> insert into myTable(ID, value)values (14,25.37); 1 row created. SQL> insert into myTable(ID, value)values (15,918.3); 1 row created. SQL> insert into myTable(ID, value)values (16,9.23); 1 row created. SQL> insert into myTable(ID, value)values (17,8.23); 1 row created. SQL> SQL> select * from myTable
2 / ID VALUE
----------
1 9 2 2.11 3 3.44 4 -4.21 5 10 6 3 7 -5.88 8 123.45 9 98.23 10 938.23 11 984.23 ID VALUE
----------
12 198.23 13 928.87 14 25.37 15 918.3 16 9.23 17 8.23
17 rows selected. SQL> SQL> SQL> SELECT STATS_F_TEST(1.2, value, "DF_DEN") FROM myTable; STATS_F_TEST(1.2,VALUE,"DF_DEN")
SQL> SQL> SQL> -- clean the table SQL> drop table myTable
2 /
Table dropped.</source>