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The Effects of Sanction Intensity on Criminal Conduct - JDAI Helpdesk

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esearch design, outcomes, and different levels <str<strong>on</strong>g>of</str<strong>on</strong>g> each moderator variable. <str<strong>on</strong>g>The</str<strong>on</strong>g>refore,<br />

we focus <strong>on</strong>ly <strong>on</strong> bivariate comparis<strong>on</strong>s <strong>on</strong> each moderator, and do not attempt to model<br />

outcomes any further. This is a limitati<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> our moderator analysis: the results we<br />

present do not c<strong>on</strong>trol for the presence <str<strong>on</strong>g>of</str<strong>on</strong>g> any additi<strong>on</strong>al moderators.<br />

<str<strong>on</strong>g>The</str<strong>on</strong>g> analog to the ANOVA is based <strong>on</strong> the Q-statistic calculated as part <str<strong>on</strong>g>of</str<strong>on</strong>g> the<br />

main random effects model. Q is the weighted sum-<str<strong>on</strong>g>of</str<strong>on</strong>g>-squares <str<strong>on</strong>g>of</str<strong>on</strong>g> each effect size around<br />

the grand mean. It represents the extent to which differences between the effect sizes are<br />

statistically related to differences in moderators (a statistically significant Q-statistic<br />

indicates evidence <str<strong>on</strong>g>of</str<strong>on</strong>g> between-study heterogeneity). We use the random effects analog to<br />

the ANOVA (also called a ‘mixed effects’ model), which assumes there is still<br />

unmeasured variability after moderators are modeled. We justify this <strong>on</strong> the basis <str<strong>on</strong>g>of</str<strong>on</strong>g> our<br />

limited set <str<strong>on</strong>g>of</str<strong>on</strong>g> moderators, which are unlikely to explain all the variability between<br />

studies. 11<br />

<str<strong>on</strong>g>The</str<strong>on</strong>g> relevant formulas are presented in Appendix C. <str<strong>on</strong>g>The</str<strong>on</strong>g>se analyses are also<br />

performed using the STATA macros.<br />

Due to the greater risk <str<strong>on</strong>g>of</str<strong>on</strong>g> bias in n<strong>on</strong>-randomized studies, experimental and quasiexperimental<br />

results are treated separately in all analyses. Randomized experiments that<br />

indicate large baseline differences between participants <strong>on</strong> characteristics likely to be<br />

related to outcomes (such as prior <str<strong>on</strong>g>of</str<strong>on</strong>g>fending history), or which experienced substantial<br />

attriti<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> participants or other implementati<strong>on</strong> problems are analyzed with the quasiexperiments.<br />

<str<strong>on</strong>g>The</str<strong>on</strong>g> c<strong>on</strong>cern with such experiments is that the attriti<strong>on</strong> may be caused by<br />

reas<strong>on</strong>s related to the treatment and/or outcome; for example, higher-risk <str<strong>on</strong>g>of</str<strong>on</strong>g>fenders may<br />

be more likely to absc<strong>on</strong>d from probati<strong>on</strong> and be subsequently lost to follow-up, thus<br />

<str<strong>on</strong>g>of</str<strong>on</strong>g>fending outcomes for the remaining lower-risk <str<strong>on</strong>g>of</str<strong>on</strong>g>fenders are biased.<br />

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