BACKGROUND Studies of the physical activity intention-behavior gap, and factors that may moderate the gap (e.g., habit, perceived behavioral control), can inform physical activity promotion efforts. Yet, these studies typically apply linear modeling procedures, and so conclusions rely on linearity and homoscedasticity assumptions, which may not hold. METHODS We modelled and plotted physical activity intention-behavior associations and the moderation effects of habit using simulated data based on (a) normal distributions with no shared variance, (b) correlated parameters with normal distribution, and (c) realistically correlated and non-normally distributed parameters. RESULTS In the uncorrelated and correlated normal distribution datasets, no violations were unmet, and the moderation effects applied across the entire data range. However, because in the realistic dataset, few people who engaged in physical activity behavior had low intention scores, the intention-behavior association was non-linear, resulting in inflated linear moderation estimations of habit. This finding was replicated when tested with intention-behavior moderation of perceived behavioral control. CONCLUSIONS Comparisons of the three scenarios illustrated how an identical correlation coefficient may mask different types of intention-behavior association and moderation effects. These findings highlight the risk of misinterpreting tests of the intention-behavior gap and its moderators for physical activity due to unfounded statistical assumptions. The previously well-documented moderating effects of habit, whereby the impact of intention on behavior weakens as habit strength increases, may be based on statistical byproducts of unmet model assumptions.

中文翻译：

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我们如何误解体育活动的意图-行为关系以及如何做。

背景技术对体育锻炼意图-行为鸿沟以及可能减轻鸿沟的因素（例如习惯，感知的行为控制）的研究可以为体育锻炼的促进工作提供信息。然而，这些研究通常采用线性建模程序，因此结论依赖于线性和均方差性假设，这可能不成立。方法我们使用模拟数据，基于（a）没有共享方差的正态分布，（b）具有正态分布的相关参数以及（c）现实相关和非正态分布的参数。结果在不相关和相关的正态分布数据集中，没有违反没有得到满足，并且在整个数据范围内应用了调节作用。然而，因为在现实的数据集中，很少有从事体育活动行为的人的意向得分低，所以意向行为关联是非线性的，从而导致习惯的线性适度估计膨胀。当用感知到的行为控制的意图-行为适度进行测试时，这一发现便得到了重复。结论三种情况的比较说明了相同的相关系数如何掩盖不同类型的意图-行为关联和调节作用。这些发现强调了由于无根据的统计假设而可能会误解对意图-行为鸿沟及其对体育活动的调节器的测试的风险。以前有据可查的习惯调节作用，随着习惯强度的增加，意图对行为的影响减弱，