FIGURE 1 TYPE I AND TYPE II ERRORS
Proper Course of Action Take No Action Take Action Take No I II Action Correct Type I Decision Error Decision Take III IV Action Type II Correct Error Decision FIGURE 2 THE BASIC DECISION MATRIX OF POLICYMAKERS Choice 1 Choice 2 Incremental Dramatic Action Action--Mild No Mitigation Action Proper Course of Action I II Correct Decision Type I Error III IV Type II Error
Correct Decision TABLE 1 FOUNDATIONS OF CONSTRUCTIVIST VS.
Cohen (1988) suggested that the Type II error
risk should be 4 times as great as the Type I error risk to ensure adequate analyses without having to use unrealistically high sample sizes for social science research.
Although previous statistical methods give data on quantity of type I error to researchers, the occurrence of type II error
mostly remains unknown (Stefano, 2001).
Courts, agencies, and academics have reacted to antitrust's unusual vulnerability to error by adopting a bias in favor of false negatives (Type II errors
For most groups, Type II error
is large relative to Type I error.
Empirical studies (e.g., Ferron, Foster-Johnson, & Kromrey, 2003; Ferron & Ware, 1995) concur with the latter statement showing that Type II errors
ate the main problem, while Type I errors ate usually controlled.
A Type II error
in this experiment occurs when R = 1 and P < 1.
When FDA commits a Type I error, "the status quo will be disrupted and people will die much sooner than they otherwise would." When the agency commits a Type II error
, people will be denied a treatment for their illness, but "the status quo will remain" (p.
Classification Error Rates and Accuracy Levels of 354 mixed industry firms and 40 retail industry firms Year 1 Year 2 Year 3 Mixed Industries Type I error 15% (15%) 30% (30%) 36% (37%) Type II error
10% (11%) 12% (14%) 16% (18%) Overall error 12% (13%) 21% (22%) 26% (27%) Overall accuracy of classification 88% (87%) 79% (78%) 74% (73%) Retail Industry Type I error 30% (30%) 65% (65%) 50% (50%) Type II error
10% (10%) 5% (5%) 10% (10%) Overall error 20% (20%) 35% (35%) 30% (30%) Overall accuracy of classification 80% (80%) 65% (65%) 70% (70%) Note: 1) B--bankrupt firms; NB--nonbankrupt firms 2) Type I error = misclassification of bankrupt firms 3) Type II error
= misclassification of nonbankrupt firms 4) Cutoff value = 0.5 5) Year 1 means 1 year before bankruptcy, and so on.
[TrT.sub.A] = Type II error
Correct decision Type II error
The second class of errors, termed Type II errors
or false negatives, occur when the system fails to detect or identify that which the system has been designed to look for.
Given the possibility of a type II error
and the absence of any downside to involvement with Alcoholics Anonymous, an argument can be made for continuing to refer patients to this group.