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242                                                 R. Seri and D. Secchi

            Table 11.2 OLS Regression                       Model 5   Model 40
            Results (DV: decisions by
            resolution/decisions by         (Intercept)     0:052     0:056
            oversight)                        St. err.       (0.006)  (0.002)
                                              t value        8.721     29.804
                                            Type: HC/AR       0:005   0:007
                                              St. err.       (0.009)  (0.003)
                                              t value         0:542    2:692
                                            Type: HI/AR       0:013   0:012
                                              St. err.       (0.009)  (0.003)
                                              t value         1:481    4:637
                                            R-squared        0.157     0.156
                                            F-statistic      1.123     10.842
                                            Degrees of freedom  2, 12  2, 117
                                            p-value          0.357     0.000
                                            N                 15        120
                                           Note. HC hierarchy-competence, HI hierarchy-
                                           incompetence, AR anarchy
                                           Signif. codes: 0 “***” 0.001 “**” 0.01 “ ” 1


              On the basis of the previous reasonings, taking into account the expository nature
            of this example, we decided to take n D 40, consistently with a value of f around
            0:4. In Table 11.2 we reproduce the estimation results for a model with 5 runs
            (i.e. Model 5), that is clearly under-powered, and for a model with 40 runs (i.e.
            Model 40), that is correctly powered under an effect size f equal to 0:40. We expect
            therefore the second model to provide a test of the effect of parameters on the
            number of decisions by resolution in comparison to those made by oversight, with
            the desired levels of ˛ and ˇ.


            11.4.2.2  The Impact of Under-Power on Outcomes


            The previous discussion shows that 5 runs should still be insufficient to provide
            reliable results. Let us see how. As stated above, we are interested in understanding
            whether the number of decisions by resolution on those by oversight change
            (decrease) as we move from anarchy to hierarchy. Hence, we can perform an OLS
                    14
            regression and produce a table with results calculated on 5 and 40 runs, to compare
            findings from an under-powered to those from an appropriately-powered study.
            Table 11.2 shows these comparisons and refers to them as Model 5 for the under-
            powered and Model 40 for the balanced simulation.




            14
             See the Appendix for details on how the effect size of the ANOVA and OLS regressions map
            onto each other.
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