To summarize here, the difference between a fully and a sparsely connected layer is that in the former, every input must receive an output from each of the previous nodes. This is not the case in a sparsely connected layer -- in the diagram on the right, the each of the middle layer's nodes only get input from 3 output nodes.
To summarize here, the difference between a fully and a sparsely connected layer is that in the former, every input must receive an output from each of the previous nodes. This is not the case in a sparsely connected layer -- in the diagram on the right, the each of the middle layer's nodes only get input from 3 output nodes.