fully connected layer
In plain wordsA layer in which every input is connected to every output by its own adjustable weight. It is the most general and most common kind of neural-network layer.
A layerlayer, n.: One stage in a neural network: a group of artificial neurons that all take the same input, transform it, and pass the result on to the next stage. that applies an affine map y = Wx + b to its whole input vector, usually followed by an activation functionactivation function, n.: The simple rule each artificial neuron applies to its total input to decide its output, such as 'keep positive values, turn negatives into zero'. Without it, a deep network would be no smarter than a single layer.: every output unit is connected to every input unit by its own weight, so a layer from n inputs to m outputs has m·n weights and m biases. Stacked, such layers form a multilayer perceptronmultilayer perceptron, n.: A neural network made of several layers of artificial neurons, each connected to every neuron in the next layer. It is the simplest kind of deep network and a component of almost every modern model.; in CNNsconvolutional neural network, n.: A kind of neural network built for images and other grid-like data. It slides small pattern detectors across the input, finding edges first, then shapes, then whole objects. they traditionally formed the final classification head, and in transformerstransformer, n.: The design behind today's chatbots and much of modern AI. It handles text by letting every word look at every other word and decide which of them matter for understanding it. they make up the attention projections and the feed-forward networkfeed-forward network, n.: The part of each transformer layer that works on every word separately, after attention has mixed in context. It holds most of a model's adjustable numbers and is thought to store much of its knowledge. sublayers, which together hold most of the parameters. PyTorch calls it Linear and Keras Dense. Because it imposes no structure on its input, it carries no built-in inductive biasinductive bias, n.: The assumptions built into a learning method that decide how it fills the gaps between the examples it was shown, such as that similar inputs get similar answers. Every learner needs some to cope with new cases. such as locality or weight sharingweight sharing, n.: Reusing the same learned numbers in many places in a network, for example one edge detector applied at every spot in an image, so the network needs fewer parameters and learns from less data.; in a convolutional network it is equivalent to a convolution whose kernel covers the whole input.
The classification head is a single fully connected layer from 768 features to 10 classes.
Origin
Full connectivity between successive layers was the default in connectionist models from the perceptron era onward. 'Fully connected' became the usual name as convolutional networks, with their locally connected, weight-shared layers, needed a contrasting term; 'dense' and 'linear' are the names used by the Keras and PyTorch libraries.
Related
- layerlayer, n.: One stage in a neural network: a group of artificial neurons that all take the same input, transform it, and pass the result on to the next stage.
- multilayer perceptronmultilayer perceptron, n.: A neural network made of several layers of artificial neurons, each connected to every neuron in the next layer. It is the simplest kind of deep network and a component of almost every modern model.
- feed-forward networkfeed-forward network, n.: The part of each transformer layer that works on every word separately, after attention has mixed in context. It holds most of a model's adjustable numbers and is thought to store much of its knowledge.
- linear transformationlinear transformation, n.: A rule for moving every point in a space that keeps straight lines straight and the origin in place: rotating, stretching, reflecting or squashing everything evenly. Every grid of numbers describes one.
- weightsweights, n.: The learned numbers inside a neural network that set how strongly each part influences the next. The finished set of weights is, in effect, the trained model itself.
- convolutional neural networkconvolutional neural network, n.: A kind of neural network built for images and other grid-like data. It slides small pattern detectors across the input, finding edges first, then shapes, then whole objects.
- convolutionconvolution, n.: An operation that slides a small grid of weights across an image or signal, multiplying and adding at each spot, to measure how strongly a pattern appears at every location.
Mentioned in
layerlayer, n.: One stage in a neural network: a group of artificial neurons that all take the same input, transform it, and pass the result on to the next stage., convolutional neural networkconvolutional neural network, n.: A kind of neural network built for images and other grid-like data. It slides small pattern detectors across the input, finding edges first, then shapes, then whole objects., multilayer perceptronmultilayer perceptron, n.: A neural network made of several layers of artificial neurons, each connected to every neuron in the next layer. It is the simplest kind of deep network and a component of almost every modern model., poolingpooling, n.: A step in an image network that shrinks its internal picture by summarizing each small patch with one number, usually the largest or the average, keeping what matters and discarding exact positions., fully convolutional networkfully convolutional network, n.: An image network made only of scanning-window layers, with no fixed-size final layers, so it can take pictures of any size and label every pixel., InceptionInception, prop. n.: A family of Google image-recognition networks, the first called GoogLeNet, whose building blocks examine each patch of an image at several scales at once while keeping computation low., squeeze-and-excitation networksqueeze-and-excitation network, n.: An image-network design whose add-on blocks let the network decide, for each picture, which of its internal feature channels to turn up and which to turn down., VGGNetVGGNet, prop. n.: An influential 2014 image-recognition network from Oxford, built by stacking many identical small pattern detectors, which showed that making networks deeper by itself improves accuracy.