confidence improvement accuracy (*)   (**)   (***)
test_runner/global-concurrent-tests.js type='async' n=100                                                  **     -5.62 %       ±3.69% ±4.92%  ±6.40%
test_runner/global-concurrent-tests.js type='async' n=1000                                                        -3.01 %       ±6.33% ±8.43% ±10.97%
test_runner/global-concurrent-tests.js type='async' n=10000                                               ***    -11.68 %       ±1.86% ±2.48%  ±3.24%
test_runner/global-concurrent-tests.js type='sync' n=100                                                   **     -8.29 %       ±5.45% ±7.25%  ±9.46%
test_runner/global-concurrent-tests.js type='sync' n=1000                                                         -3.87 %       ±5.29% ±7.04%  ±9.17%
test_runner/global-concurrent-tests.js type='sync' n=10000                                                ***    -12.91 %       ±1.85% ±2.46%  ±3.21%
test_runner/global-sequential-tests.js type='async' n=100                                                         -0.55 %       ±1.62% ±2.16%  ±2.81%
test_runner/global-sequential-tests.js type='async' n=1000                                                         0.71 %       ±2.49% ±3.32%  ±4.33%
test_runner/global-sequential-tests.js type='async' n=10000                                                        0.68 %       ±1.50% ±2.00%  ±2.62%
test_runner/global-sequential-tests.js type='sync' n=100                                                           0.01 %       ±1.30% ±1.74%  ±2.26%
test_runner/global-sequential-tests.js type='sync' n=1000                                                          1.20 %       ±1.40% ±1.86%  ±2.42%
test_runner/global-sequential-tests.js type='sync' n=10000                                                         1.13 %       ±2.15% ±2.88%  ±3.77%
test_runner/multi-files.js concurrency='no' patterns='test/fixtures/test-runner/**/*.?(c|m)js'                     0.02 %       ±0.64% ±0.85%  ±1.11%
test_runner/multi-files.js concurrency='no' patterns='test/parallel/test-runner-*'                                -0.37 %       ±0.99% ±1.32%  ±1.72%
test_runner/multi-files.js concurrency='yes' patterns='test/fixtures/test-runner/**/*.?(c|m)js'                   -0.06 %       ±0.45% ±0.60%  ±0.78%
test_runner/multi-files.js concurrency='yes' patterns='test/parallel/test-runner-*'                                0.80 %       ±4.69% ±6.29%  ±8.29%
test_runner/suite-tests.js concurrency='no' testType='async' testsPerSuite=10 numberOfSuites=10           ***    -16.52 %       ±7.34% ±9.79% ±12.79%
test_runner/suite-tests.js concurrency='no' testType='async' testsPerSuite=10 numberOfSuites=100                  -5.35 %       ±6.64% ±8.83% ±11.49%
test_runner/suite-tests.js concurrency='no' testType='async' testsPerSuite=100 numberOfSuites=10            *     -7.93 %       ±6.35% ±8.46% ±11.03%
test_runner/suite-tests.js concurrency='no' testType='async' testsPerSuite=100 numberOfSuites=100         ***    -15.74 %       ±3.83% ±5.12%  ±6.69%
test_runner/suite-tests.js concurrency='no' testType='sync' testsPerSuite=10 numberOfSuites=10             **     -9.80 %       ±5.75% ±7.66%  ±9.97%
test_runner/suite-tests.js concurrency='no' testType='sync' testsPerSuite=10 numberOfSuites=100                   -6.93 %       ±7.02% ±9.34% ±12.16%
test_runner/suite-tests.js concurrency='no' testType='sync' testsPerSuite=100 numberOfSuites=10            **    -10.70 %       ±6.46% ±8.62% ±11.27%
test_runner/suite-tests.js concurrency='no' testType='sync' testsPerSuite=100 numberOfSuites=100          ***    -15.67 %       ±4.25% ±5.67%  ±7.40%
test_runner/suite-tests.js concurrency='yes' testType='async' testsPerSuite=10 numberOfSuites=10           **     -9.35 %       ±5.73% ±7.62%  ±9.92%
test_runner/suite-tests.js concurrency='yes' testType='async' testsPerSuite=10 numberOfSuites=100                 -3.61 %       ±7.13% ±9.49% ±12.35%
test_runner/suite-tests.js concurrency='yes' testType='async' testsPerSuite=100 numberOfSuites=10                 -5.42 %       ±6.65% ±8.86% ±11.53%
test_runner/suite-tests.js concurrency='yes' testType='async' testsPerSuite=100 numberOfSuites=100        ***    -15.05 %       ±4.11% ±5.48%  ±7.14%
test_runner/suite-tests.js concurrency='yes' testType='sync' testsPerSuite=10 numberOfSuites=10           ***    -15.59 %       ±6.39% ±8.52% ±11.13%
test_runner/suite-tests.js concurrency='yes' testType='sync' testsPerSuite=10 numberOfSuites=100                  -3.53 %       ±6.85% ±9.12% ±11.87%
test_runner/suite-tests.js concurrency='yes' testType='sync' testsPerSuite=100 numberOfSuites=10                  -2.89 %       ±3.45% ±4.63%  ±6.11%
test_runner/suite-tests.js concurrency='yes' testType='sync' testsPerSuite=100 numberOfSuites=100         ***    -14.85 %       ±4.63% ±6.17%  ±8.04%

Be aware that when doing many comparisons the risk of a false-positive
result increases. In this case, there are 32 comparisons, you can thus
expect the following amount of false-positive results:
  1.60 false positives, when considering a   5% risk acceptance (*, **, ***),
  0.32 false positives, when considering a   1% risk acceptance (**, ***),
  0.03 false positives, when considering a 0.1% risk acceptance (***)