边缘检测产生的非高斯后验
Non-Gaussian Posteriors arising from Marginal Detections
摘要:
我们指出,在边缘检测(~ 3σ)的情况下,如宇宙学中的重子声振荡(BAO),通常使用的高斯近似的全似然是非常差的,特别是超过~3σ。这可以从根本上改变参数的置信区间,并意味着不能天真地将1σ误差棒外推到3σ及以上。我们提出了一个简单的拟合公式,它纠正了这种影响所产生的边缘检测后验概率。或者,完全似然应该用于参数估计,而不是高斯近似的平均值和误差。
英文摘要:
We show that in cases of marginal detections (~ 3σ), such as that of Baryonic Acoustic Oscillations (BAO) in cosmology, the often-used Gaussian approximation to the full likelihood is very poor, especially beyond ~3σ. This can radically alter confidence intervals on parameters and implies that one cannot naively extrapolate 1σ-errorbars to 3σ, and beyond. We propose a simple fitting formula which corrects for this effect in posterior probabilities arising from marginal detections. Alternatively the full likelihood should be used for parameter estimation rather than the Gaussian approximation of a just mean and an error.
机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。