We address the claim of Weiss et al. (2018) that the radii of adjacent planets in Kepler multi-planet systems are correlated. We explore two simple toy models---in the first the radii of the planets are chosen at random from a single universal distribution, and in the second we postulate several types of system with distinct radius distributions. We show that an apparent correlation between the radii of adjacent planets similar to the one reported by Weiss et al. (2018) can arise in both models. In addition the second model fits the radius and signal-to-noise distribution of the observed planets. We also comment on the validity of a commonly used correction that is used to estimate intrinsic planet occurrence rates, based on weighting planets by the inverse of their detectability.

中文翻译：

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豆荚里的豌豆？开普勒多行星系统中的半径相关性

我们解决了 Weiss 等人的主张。(2018) 开普勒多行星系统中相邻行星的半径是相关的。我们探索了两个简单的玩具模型——第一个是从一个单一的普遍分布中随机选择行星的半径，第二个我们假设有几种类型的系统具有不同的半径分布。我们表明相邻行星的半径之间存在明显的相关性，类似于 Weiss 等人报道的。(2018) 可以出现在两种模型中。此外，第二个模型适合观测行星的半径和信噪比分布。我们还评论了一种常用校正的有效性，该校正用于估计内在行星出现率，基于通过其可检测性的倒数对行星进行加权。