Table 3. Differences between the frequencies of won actions with different types of plays (Level 2) of game fragments (Level 1) observed in three periods.
Level 1 1970-2000
(1)		 2001-2015
(2)		 2016-2021
(3)		 (1) vs. (2) (1) vs. (3) (2) vs. (3) χ2 P< Ccorr
Level 2 h-Cohen p* h-Cohen p* h-Cohen p*
1. Serve n=1164 n=521 n=412 513.0 .001 .518
  1.1. Serve fh sidespin 23.45% 46.64% 65.05% .492 <.001 .865 <.001 .373 <.001
  1.2. Serve fh backspin-no-spin 60.14% 21.50% 14.32% -.811 <.001 -.999 <.001 -.188 .005
  1.3. Serve bh sidespin 8.51% 3.84% 9.71% -.197 .001 .042 .459 .239 <.001
  1.4. Serve fh reverse 2.58% 15.16% 6.55% .477 <.001 .195 <.001 -.282 <.001
  1.5. -1.10 other 5.33% 12.86% 4.37% 0268 <.001 -.045 .447 -.312 <.001
2.Serve+Counterattack-attack n=1849 n=1145 n=1020 782.7 .001 .472
  2.1. Serve fh sidespin+Counterattack 21.90% 43.41% 60.20% .464 <.001 .802 <.001 .338 <.001
  2.2.Serve fh backspin-no-spin+Counterattack 60.36% 25.59% 18.92% -.719 <.001 -.879 <.001 -.161 <.001
  2.3. Serve bh sidespin+Counterattack 7.36% 6.11% 7.75% -.050 .192 .015 .705 .064 .135
  2.4. Serve fh reverse+Counterattack 2.16% 12.31% 7.45% .422 <.001 .258 <.001 -.164 <.001
  2.5-2.10. other 8.22% 12.58% 5.69% .143 <.001 -.100 .013 -.243 <.001
3. Return n=1507 n=777 n=754 352.3 .001 .369
  3.1. Push fh 28.14% 30.76% 24.54% .058 .191 -.082 .069 -.139 .007
  3.2. Topspin and Fast attack fh 29.66% 21.11% 13.13% -.197 <.001 -.410 <.001 -.213 <.001
  3.3. Push bh 15.99% 12.61% 15.92% -.097 .031 -.002 .962 .095 .065
  3.4. Flick bh 3.85% 16.22% 24.54% .434 <.001 .642 <.001 .208 <.001
  3.5. Flick fh 12.61% 11.58% 4.38% -.031 .479 -.304 <.001 -.273 <.001
  3.6. Topspin and Fast attack bh 4.71% 5.92% 11.94% .054 .215 .268 <.001 .214 <.001
  3.7. - 3.10 other 5.04% 1.80% 5.57% -.184 <.001 .024 .595 .207 <.001
4. Return+Counterattack n=1122 n=796 n=717 247.2 .001 .322
  4.1.Push fh+Counterattack 38.15% 48.74% 38.49% .214 <.001 .007 .881 -.207 <.001
  4.2. Push bh+Counterattack 22.55% 21.86% 29.29% -.017 .721 .154 .001 .171 .001
  4.3. Topspin-fh+Counterattack 14.97% 8.79% 3.91% -.193 <.001 -.397 <.001 -.204 <.001
  4.4. Flick-fh+Counterattack 11.59% 5.90% 3.07% -.204 <.001 -.343 <.001 -.139 .008
  4.5. Flick bh+Counterattack 2.85% 8.04% 14.23% .236 <.001 .434 <.001 .198 <.001
  4.6. Topspin-bh+Counterattack 2.67% 3.39% 5.44% .042 .362 .142 .002 .100 .052
  4.7. Chop-bh+Counterattack 1.96% .88% 2.51% -.093 .056 .037 .431 .130 .013
  4.8.Fast attack-bh+Counterattack 1.69% .88% 2.65% -.073 .129 .066 .160 .139 .008
  4.9-4.12 other 3.57% 1.51% 0.42% -.134 .006 -.250 <.001 -.117 .033
5. Attack+Counterattack n=1594 n=920 n=815 187.9 .001 .267
  5.1. Topspin-fh+Counterattack 48.37% 61.30% 47.85% .261 <.001 -.010 .810 -.271 <.001
  5.2.Fast attack-bh+Counterattack 15.75% 8.26% 22.58% -.233 <.001 .174 <.001 .407 <.001
  5.3.Fast attack-fh+Counterattack 18.19% 5.98% 9.45% -.387 <.001 -.256 <.001 .131 .007
  5.4. Topspin-bh+Counterattack 13.36% 18.26% 14.48% .135 .001 .032 .452 -.102 .034
  5.5. Flick-Fh+Counterattack 3.64% 3.59% 2.82% -.003 .947 -.046 .293 -.044 .368
  5.6. Flick-bh+Counterattack .69% 2.61% 2.82% .158 <.001 .171 <.001 .013 .785
6. Block+Counterattack n=918 n=402 n=376 29.3 .001 .142
  6.1. Block-bh+Counterattack 66.78% 67.41% 66.49% .014 .821 -.006 .921 -.020 .784
  6.2. Block-fh+Counterattack 15.25% 15.92% 13.56% .018 .757 -.048 .438 -.067 .355
  6.3. „Fishing”-bh+Counterattack 11.44% 7.46% 6.65% -.137 .028 -.168 .009 -.032 .658
  6.4. „Fishing”-fh+Counterattack 5.34% 7.46% 12.50% .087 .134 .256 <.001 .169 .019
  6.x. Lob+Counterattack 1.20% 1.74% .80% .045 .434 -.040 .527 -.086 .243
7. Push+Counterattack n=298 n=251 n=426 7.9 .019 .118
  7.1. Push-bh+Counterattack 44.63% 49.00% 38.26% 0.088 0.307 -0.129 0.087 -0.217 .784
  7.2. Push-fh+Counterattack 55.37% 51.00% 61.74% -0.088 0.307 0.129 0.087 0.217 .355
8.Attack-against-chop+Counterattack n=298 n=251 n=426 25.8 .001 .227
  8.1. Aac-Topspin-fh+Counterattack 83.82% 89.41% 90.00% 0.165 0.061 0.184 0.053 0.019 .784
  8.2. Aac-Topspin-bh+Counterattack 4.41% 8.24% 6.50% 0.159 0.071 0.092 0.317 -0.067 .355
  8.3. -8.4 other 11.76% 2.35% 3.50% -0.392 <0.001 -0.324 0.001 0.068 .355
9.Chop+Counterattack n=210 n=172 n=112 14.8 .001 0.223
  9.1. Chop-bh+Counterattack 69.05% 81.98% 85.71% 0.303 0.004 0.405 0.001 0.102 0.408
  9.2. Chop-fh+Counterattack 30.95% 18.02% 14.29% -0.303 0.004 -0.405 0.001 -0.102 0.408
10. Other n=366 n=171 n=152 28.7 .001 .245
  10.1. 'Net' or ‘edge' 57.10% 76.02% 76.32% 0.405 <0.001 0.412 <0.001 0.007 0.951
  10.2. Opponent’s serve fault 40.71% 23.39% 21.71% -0.374 <0.001 -0.415 <0.001 -0.040 0.719
  10.3. -10.5 other 2.19% 0.58% 1.97% -0.144 0.179 -0.015 0.879 0.129 0.261
h-Cohen – the value of h Cohen indicator (effect size), p* - statistical significance at p<0.017, χ2 – the value of chi-square test, p – the significance of χ2 test, Ccorr - corrected contingency coefficient