Before revision:  Although many analysis methods have been proposed to this end , most of them suffer from a mathematical difficulty that stems from the fact that activity of only a limited number of neurons are available. That is, many existing methods ignore effects from unobserved neurons. To overcome this difficulty , a novel probabilistic framework is proposed for estimating neural connections from partially observed spikes .
After revision:  Although many analysis methods have been proposed to this end , most of them suffer from one or all the following mathematical difficulties: (1) only partially observed neural activity is available; (2) correlations can include both direct and indirect pseudo-interactions; and (3) biological evidence that a neuron typically has only one type of connection (excitatory or inhibitory) should be considered. To overcome these difficulties , a novel probabilistic framework is proposed for estimating neural connections from partially observed spikes .