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The influence of the place-value structure of the Arabic number ...

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Contrarily, data produced by a two-linear model (again including some random noise) must<br />

not be fitted better by a logarithmic model. To test <strong>the</strong>se predictions we simulated <strong>the</strong> data <strong>of</strong><br />

100 participants using both a logarithmic as well as a two-linear model incorporating a<br />

Gaussian random error term and fitted <strong>the</strong> resulting data in a logarithmic and a two-linear<br />

regression analysis for each <strong>of</strong> <strong>the</strong>se modelled data sets. Subsequently, adjusted R 2 resulting<br />

from ei<strong>the</strong>r regression were compared using paired t-tests. <strong>The</strong> results <strong>of</strong> <strong>the</strong> t-tests showed<br />

that logarithmic fitting did account for reliably more variance <strong>of</strong> <strong>the</strong> data produced by a<br />

logarithmic model than did two-linear fitting [t(99) = 1.99, p < .05; R 2 log = .94 vs. R 2 two-lin =<br />

.93]. On <strong>the</strong> o<strong>the</strong>r hand, two-linear fitting resulted in a higher adjusted R 2 than did logarithmic<br />

fitting for <strong>the</strong> data produced by a two-linear model [t(99) = 10.28, p < .001; R 2 log = .87 vs.<br />

R 2 two-lin = .93]. Apart from <strong>the</strong> fact that all analyses were run on R 2 <strong>value</strong>s adjusted for<br />

differing <strong>number</strong>s <strong>of</strong> free parameters this finding again argues against an overfitting <strong>of</strong> <strong>the</strong><br />

empirical data by <strong>the</strong> two-linear model.<br />

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