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Statistical Tables | Power for Eta-Squared

Two-Tailed Probabilities (p) for a Single-Factor Design with dfEFFECT = 2 (α = .05) Given Eta-Squared and Sample Size per Condition (n)

n 0.01 0.02 0.04 0.06 0.09 0.12 0.16 0.20 0.25 0.30 0.36 0.42 0.49 0.56 0.64 0.72
3 .053 .056 .062 .069 .079 .091 .108 .127 .154 .186 .232 .288 .368 .467 .608 .770
4 .055 .060 .071 .083 .102 .123 .154 .190 .241 .299 .381 .473 .594 .722 .860 .957
5 .057 .065 .081 .098 .127 .158 .205 .258 .333 .415 .523 .637 .765 .876 .960 .994
6 .059 .069 .091 .114 .152 .195 .258 .328 .424 .525 .647 .763 .875 .950 .990 .999
7 .062 .074 .101 .131 .179 .233 .312 .398 .510 .622 .747 .852 .937 .982 .998 >.999
8 .064 .079 .112 .147 .207 .272 .366 .465 .588 .705 .824 .911 .970 .994 >.999 >.999
9 .066 .084 .122 .165 .235 .311 .418 .528 .659 .773 .880 .948 .986 .998 >.999 >.999
10 .069 .089 .133 .182 .263 .350 .469 .587 .720 .829 .920 .970 .994 .999 >.999 >.999
11 .071 .094 .145 .200 .291 .388 .518 .641 .772 .872 .947 .983 .997 >.999 >.999 >.999
12 .074 .099 .156 .218 .320 .425 .564 .689 .817 .906 .966 .991 .999 >.999 >.999 >.999
13 .076 .104 .167 .237 .348 .462 .607 .733 .853 .931 .978 .995 >.999 >.999 >.999 >.999
14 .079 .110 .179 .255 .376 .497 .647 .772 .884 .950 .986 .997 >.999 >.999 >.999 >.999
15 .081 .115 .191 .273 .403 .531 .684 .806 .908 .964 .991 .999 >.999 >.999 >.999 >.999
16 .083 .120 .202 .292 .430 .564 .718 .836 .928 .975 .995 .999 >.999 >.999 >.999 >.999
17 .086 .126 .214 .310 .457 .595 .750 .861 .944 .982 .997 >.999 >.999 >.999 >.999 >.999
18 .088 .131 .226 .328 .483 .625 .778 .884 .957 .987 .998 >.999 >.999 >.999 >.999 >.999
19 .091 .137 .238 .346 .508 .653 .804 .903 .967 .991 .999 >.999 >.999 >.999 >.999 >.999
20 .093 .142 .250 .364 .533 .680 .827 .919 .975 .994 .999 >.999 >.999 >.999 >.999 >.999
21 .096 .148 .262 .382 .556 .705 .848 .933 .981 .996 >.999 >.999 >.999 >.999 >.999 >.999
22 .099 .153 .274 .400 .579 .728 .867 .944 .985 .997 >.999 >.999 >.999 >.999 >.999 >.999
23 .101 .159 .286 .418 .602 .750 .883 .954 .989 .998 >.999 >.999 >.999 >.999 >.999 >.999
24 .104 .164 .298 .435 .623 .771 .898 .962 .992 .999 >.999 >.999 >.999 >.999 >.999 >.999
25 .106 .170 .310 .452 .644 .790 .911 .969 .994 .999 >.999 >.999 >.999 >.999 >.999 >.999
26 .109 .176 .322 .469 .664 .808 .923 .975 .995 .999 >.999 >.999 >.999 >.999 >.999 >.999
27 .111 .181 .334 .486 .683 .825 .933 .979 .996 >.999 >.999 >.999 >.999 >.999 >.999 >.999
28 .114 .187 .346 .502 .701 .840 .942 .983 .997 >.999 >.999 >.999 >.999 >.999 >.999 >.999
29 .117 .193 .357 .518 .718 .854 .950 .986 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999
30 .119 .199 .369 .534 .735 .867 .957 .989 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
35 .133 .228 .427 .608 .807 .919 .980 .996 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
40 .146 .257 .482 .674 .862 .951 .991 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
45 .160 .286 .535 .731 .903 .972 .996 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
50 .174 .316 .584 .780 .932 .984 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
55 .188 .345 .630 .821 .954 .991 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
60 .203 .374 .672 .856 .968 .995 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
70 .231 .430 .745 .909 .986 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
80 .260 .485 .805 .943 .994 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
90 .290 .536 .853 .965 .997 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
100 .319 .584 .890 .979 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
120 .376 .670 .940 .993 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
240 .669 .938 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
360 .847 .991 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999

Two-Tailed Probabilities (p) for a Single-Factor Design with dfEFFECT = 3 (α = .05) Given Eta-Squared and Sample Size per Condition (n)

n 0.01 0.02 0.04 0.06 0.09 0.12 0.16 0.20 0.25 0.30 0.36 0.42 0.49 0.56 0.64 0.72
3 .053 .056 .063 .070 .082 .095 .114 .136 .168 .207 .261 .328 .424 .540 .695 .854
4 .055 .061 .073 .085 .107 .131 .167 .208 .269 .338 .433 .540 .674 .803 .921 .984
5 .058 .066 .083 .102 .134 .171 .225 .288 .375 .472 .594 .715 .840 .932 .985 .999
6 .060 .071 .094 .120 .164 .213 .287 .369 .480 .594 .724 .836 .930 .980 .998 >.999
7 .062 .076 .105 .138 .194 .257 .350 .449 .576 .697 .821 .912 .972 .995 >.999 >.999
8 .065 .081 .117 .158 .226 .302 .412 .525 .661 .780 .888 .955 .989 .999 >.999 >.999
9 .067 .086 .129 .177 .258 .348 .472 .595 .734 .844 .933 .978 .996 >.999 >.999 >.999
10 .070 .092 .141 .198 .291 .392 .530 .659 .794 .892 .960 .989 .999 >.999 >.999 >.999
11 .073 .097 .154 .218 .324 .437 .584 .715 .843 .927 .977 .995 >.999 >.999 >.999 >.999
12 .075 .103 .167 .239 .357 .479 .634 .764 .882 .951 .987 .998 >.999 >.999 >.999 >.999
13 .078 .109 .180 .260 .390 .521 .679 .806 .912 .968 .993 .999 >.999 >.999 >.999 >.999
14 .080 .115 .193 .281 .422 .560 .721 .842 .935 .979 .996 >.999 >.999 >.999 >.999 >.999
15 .083 .121 .207 .303 .454 .598 .759 .872 .953 .986 .998 >.999 >.999 >.999 >.999 >.999
16 .086 .126 .220 .324 .485 .633 .792 .897 .966 .991 .999 >.999 >.999 >.999 >.999 >.999
17 .088 .132 .234 .346 .515 .667 .822 .918 .975 .995 .999 >.999 >.999 >.999 >.999 >.999
18 .091 .139 .248 .367 .544 .698 .848 .935 .983 .997 >.999 >.999 >.999 >.999 >.999 >.999
19 .094 .145 .261 .388 .572 .727 .870 .948 .988 .998 >.999 >.999 >.999 >.999 >.999 >.999
20 .097 .151 .275 .409 .599 .754 .890 .959 .991 .999 >.999 >.999 >.999 >.999 >.999 >.999
21 .099 .157 .289 .430 .625 .778 .907 .968 .994 .999 >.999 >.999 >.999 >.999 >.999 >.999
22 .102 .164 .303 .450 .650 .801 .922 .975 .996 >.999 >.999 >.999 >.999 >.999 >.999 >.999
23 .105 .170 .317 .470 .674 .822 .935 .981 .997 >.999 >.999 >.999 >.999 >.999 >.999 >.999
24 .108 .176 .331 .490 .696 .841 .945 .985 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999
25 .111 .183 .345 .509 .717 .858 .954 .989 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
26 .114 .189 .359 .528 .738 .874 .962 .991 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
27 .117 .196 .373 .547 .757 .888 .969 .993 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
28 .119 .202 .387 .565 .775 .901 .974 .995 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
29 .122 .209 .401 .583 .792 .912 .979 .996 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
30 .125 .216 .414 .600 .807 .922 .982 .997 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
35 .140 .249 .480 .680 .873 .959 .994 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
40 .156 .283 .543 .747 .918 .979 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
45 .171 .318 .601 .803 .948 .990 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
50 .187 .352 .654 .849 .968 .995 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
55 .204 .386 .703 .885 .981 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
60 .220 .419 .746 .913 .988 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
70 .254 .484 .817 .952 .996 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
80 .287 .545 .871 .975 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
90 .321 .602 .911 .987 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
100 .355 .654 .939 .993 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
120 .422 .744 .973 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
240 .743 .971 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
360 .906 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999

Two-Tailed Probabilities (p) for a Single-Factor Design with dfEFFECT = 2 (α = .01) Given Eta-Squared and Sample Size per Condition (n)

n 0.01 0.02 0.04 0.06 0.09 0.12 0.16 0.20 0.25 0.30 0.36 0.42 0.49 0.56 0.64 0.72
3 .011 .011 .013 .015 .018 .021 .026 .031 .040 .051 .067 .089 .124 .175 .264 .408
4 .011 .013 .016 .019 .025 .032 .042 .056 .076 .102 .143 .198 .283 .399 .573 .775
5 .012 .014 .019 .024 .034 .045 .064 .088 .125 .172 .244 .337 .470 .627 .809 .945
6 .013 .016 .022 .030 .044 .062 .090 .126 .183 .254 .358 .482 .642 .797 .930 .990
7 .013 .017 .026 .037 .056 .080 .120 .170 .248 .342 .473 .615 .775 .901 .978 .999
8 .014 .019 .030 .043 .069 .100 .153 .218 .317 .432 .581 .727 .867 .956 .994 >.999
9 .015 .021 .034 .051 .083 .123 .189 .270 .388 .518 .675 .813 .926 .981 .999 >.999
10 .016 .022 .039 .059 .098 .146 .227 .322 .457 .598 .755 .876 .960 .993 >.999 >.999
11 .017 .024 .043 .067 .114 .172 .266 .376 .524 .670 .819 .921 .980 .997 >.999 >.999
12 .017 .026 .048 .076 .130 .198 .307 .429 .587 .733 .869 .950 .990 .999 >.999 >.999
13 .018 .028 .053 .086 .148 .226 .347 .481 .645 .787 .906 .970 .995 >.999 >.999 >.999
14 .019 .030 .058 .095 .167 .254 .388 .531 .698 .832 .934 .982 .998 >.999 >.999 >.999
15 .020 .032 .064 .106 .186 .283 .429 .578 .745 .869 .955 .989 .999 >.999 >.999 >.999
16 .021 .034 .070 .116 .205 .312 .469 .623 .786 .899 .969 .994 >.999 >.999 >.999 >.999
17 .022 .036 .076 .127 .225 .341 .507 .665 .822 .923 .979 .996 >.999 >.999 >.999 >.999
18 .023 .039 .082 .138 .246 .371 .545 .703 .853 .941 .986 .998 >.999 >.999 >.999 >.999
19 .023 .041 .088 .150 .266 .400 .581 .739 .879 .956 .991 .999 >.999 >.999 >.999 >.999
20 .024 .043 .094 .162 .288 .429 .615 .771 .901 .967 .994 .999 >.999 >.999 >.999 >.999
21 .025 .046 .101 .174 .309 .458 .648 .800 .920 .976 .996 >.999 >.999 >.999 >.999 >.999
22 .026 .048 .108 .187 .330 .486 .678 .826 .935 .982 .998 >.999 >.999 >.999 >.999 >.999
23 .027 .050 .115 .199 .352 .513 .707 .849 .948 .987 .998 >.999 >.999 >.999 >.999 >.999
24 .028 .053 .122 .212 .373 .540 .734 .870 .959 .990 .999 >.999 >.999 >.999 >.999 >.999
25 .029 .056 .129 .225 .394 .566 .759 .888 .967 .993 .999 >.999 >.999 >.999 >.999 >.999
26 .030 .058 .136 .238 .415 .592 .783 .904 .974 .995 >.999 >.999 >.999 >.999 >.999 >.999
27 .031 .061 .144 .252 .436 .616 .804 .918 .979 .996 >.999 >.999 >.999 >.999 >.999 >.999
28 .032 .064 .151 .265 .457 .640 .824 .930 .984 .998 >.999 >.999 >.999 >.999 >.999 >.999
29 .033 .066 .159 .279 .478 .662 .842 .940 .987 .998 >.999 >.999 >.999 >.999 >.999 >.999
30 .034 .069 .167 .292 .498 .684 .859 .950 .990 .999 >.999 >.999 >.999 >.999 >.999 >.999
35 .040 .084 .208 .361 .593 .777 .921 .979 .997 >.999 >.999 >.999 >.999 >.999 >.999 >.999
40 .046 .100 .251 .430 .677 .848 .958 .992 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
45 .052 .117 .296 .496 .749 .899 .978 .997 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
50 .058 .134 .341 .559 .807 .934 .989 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
55 .065 .153 .386 .618 .855 .958 .995 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
60 .072 .172 .430 .671 .892 .974 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
70 .087 .213 .516 .762 .942 .990 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
80 .103 .255 .596 .833 .971 .997 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
90 .119 .299 .667 .885 .986 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
100 .137 .343 .730 .923 .993 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
120 .175 .431 .828 .967 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
240 .431 .823 .994 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
360 .662 .962 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999

Two-Tailed Probabilities (p) for a Single-Factor Design with dfEFFECT = 3 (α = .01) Given Eta-Squared and Sample Size per Condition (n)

n 0.01 0.02 0.04 0.06 0.09 0.12 0.16 0.20 0.25 0.30 0.36 0.42 0.49 0.56 0.64 0.72
3 .011 .012 .013 .015 .018 .022 .028 .035 .046 .060 .081 .111 .160 .232 .355 .542
4 .011 .013 .016 .020 .027 .035 .048 .064 .091 .125 .180 .253 .366 .511 .706 .889
5 .012 .014 .020 .026 .037 .051 .074 .104 .152 .214 .308 .425 .585 .751 .907 .985
6 .013 .016 .023 .032 .049 .070 .106 .152 .226 .317 .447 .593 .760 .894 .978 .999
7 .014 .018 .028 .040 .063 .093 .143 .208 .307 .425 .579 .731 .875 .961 .996 >.999
8 .014 .019 .032 .048 .078 .118 .185 .268 .392 .530 .693 .833 .940 .987 .999 >.999
9 .015 .021 .037 .057 .095 .145 .230 .332 .476 .625 .785 .902 .973 .996 >.999 >.999
10 .016 .023 .042 .066 .114 .175 .277 .396 .556 .709 .854 .945 .989 .999 >.999 >.999
11 .017 .025 .047 .076 .134 .207 .326 .460 .630 .778 .904 .970 .996 >.999 >.999 >.999
12 .018 .027 .053 .087 .154 .240 .375 .522 .696 .835 .939 .984 .998 >.999 >.999 >.999
13 .019 .030 .059 .098 .177 .274 .425 .580 .753 .879 .962 .992 .999 >.999 >.999 >.999
14 .019 .032 .065 .110 .200 .309 .473 .635 .802 .913 .977 .996 >.999 >.999 >.999 >.999
15 .020 .034 .072 .123 .223 .345 .520 .685 .843 .938 .986 .998 >.999 >.999 >.999 >.999
16 .021 .036 .078 .136 .248 .380 .565 .730 .877 .957 .992 .999 >.999 >.999 >.999 >.999
17 .022 .039 .086 .150 .273 .416 .608 .770 .905 .970 .995 >.999 >.999 >.999 >.999 >.999
18 .023 .041 .093 .164 .298 .451 .648 .806 .927 .980 .997 >.999 >.999 >.999 >.999 >.999
19 .024 .044 .101 .178 .324 .485 .686 .837 .944 .986 .998 >.999 >.999 >.999 >.999 >.999
20 .025 .047 .108 .193 .350 .519 .721 .864 .958 .991 .999 >.999 >.999 >.999 >.999 >.999
21 .026 .050 .117 .208 .376 .551 .753 .887 .968 .994 >.999 >.999 >.999 >.999 >.999 >.999
22 .027 .052 .125 .224 .401 .583 .782 .907 .977 .996 >.999 >.999 >.999 >.999 >.999 >.999
23 .028 .055 .133 .239 .427 .613 .808 .924 .983 .997 >.999 >.999 >.999 >.999 >.999 >.999
24 .030 .058 .142 .255 .452 .642 .832 .938 .987 .998 >.999 >.999 >.999 >.999 >.999 >.999
25 .031 .061 .151 .272 .477 .670 .854 .949 .991 .999 >.999 >.999 >.999 >.999 >.999 >.999
26 .032 .064 .160 .288 .502 .696 .873 .959 .993 .999 >.999 >.999 >.999 >.999 >.999 >.999
27 .033 .068 .170 .304 .526 .721 .890 .967 .995 >.999 >.999 >.999 >.999 >.999 >.999 >.999
28 .034 .071 .179 .321 .550 .744 .905 .974 .997 >.999 >.999 >.999 >.999 >.999 >.999 >.999
29 .035 .074 .189 .338 .573 .766 .918 .979 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999
30 .036 .078 .199 .355 .595 .786 .930 .983 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999
35 .043 .095 .250 .438 .697 .868 .969 .995 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
40 .049 .115 .303 .518 .779 .922 .987 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
45 .057 .136 .358 .593 .844 .956 .995 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
50 .064 .158 .412 .661 .892 .976 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
55 .072 .181 .466 .721 .927 .987 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
60 .081 .205 .518 .773 .951 .993 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
70 .099 .255 .614 .855 .979 .998 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
80 .118 .308 .698 .910 .992 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
90 .139 .361 .769 .947 .997 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
100 .161 .414 .826 .969 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
120 .208 .518 .907 .990 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
240 .518 .903 .999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999
360 .763 .988 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999 >.999