11. While performing the McDonald Kreitman test, scientists also have to avoid making too numerous type II errors . 12. Significance testing did not utilize an alternative hypothesis so there was no concept of a Type II error . 13. A type II error occurs when letting a guilty person go free ( an error of impunity ). 14. But it did not examine whether a sound company got a low rating, known as a Type II error , Daily said. 15. Where a and b ( a ) depend on the desired type I and type II errors , \ alpha and \ beta. 16. The statistical power desired is estimated by one minus beta, where beta is equal to the probability of making a Type II error . 17. A type II error occurs when failing to detect an effect ( adding fluoride to toothpaste protects against cavities ) that is present. 18. For a fixed level of Type I error rate, use of these statistics minimizes Type II error rates ( equivalent to maximizing power ). 19. This can result in an overly conservative result that fails to reject the null hypothesis when it should ( a type II error ). 20. The probability of a type II error is dependent of the sample size and the actual difference between the sample value and the observed value.
