NTN

class NTN(*, embedding_dim=100, num_slices=4, non_linearity=None, non_linearity_kwargs=None, entity_initializer=None, **kwargs)[source]

Bases: ERModel

An implementation of NTN from [socher2013].

NTN uses a bilinear tensor layer instead of a standard linear neural network layer:

\[f(h,r,t) = \textbf{u}_{r}^{T} \cdot \tanh(\textbf{h} \mathfrak{W}_{r} \textbf{t} + \textbf{V}_r [\textbf{h};\textbf{t}] + \textbf{b}_r)\]

where \(\mathfrak{W}_r \in \mathbb{R}^{d \times d \times k}\) is the relation specific tensor, and the weight matrix \(\textbf{V}_r \in \mathbb{R}^{k \times 2d}\), and the bias vector \(\textbf{b}_r\) and the weight vector \(\textbf{u}_r \in \mathbb{R}^k\) are the standard parameters of a neural network, which are also relation specific. The result of the tensor product \(\textbf{h} \mathfrak{W}_{r} \textbf{t}\) is a vector \(\textbf{x} \in \mathbb{R}^k\) where each entry \(x_i\) is computed based on the slice \(i\) of the tensor \(\mathfrak{W}_{r}\): \(\textbf{x}_i = \textbf{h}\mathfrak{W}_{r}^{i} \textbf{t}\). As indicated by the interaction model, NTN defines for each relation a separate neural network which makes the model very expressive, but at the same time computationally expensive.

Note

We split the original \(V_r\) matrix into two parts, to separate \(V_r [h; r] = V_r^h h + V_r^t t\). The latter is more efficient, if \(h\) and \(t\) are not of the same shape, e.g., since we are in a score_h() / score_t() setting.

Initialize NTN.

Parameters:
  • embedding_dim (int) – The entity embedding dimension \(d\). Is usually \(d \in [50, 350]\).

  • num_slices (int) – The number of slices in the parameters

  • non_linearity (Union[str, Module, Type[Module], None]) – A non-linear activation function. Defaults to the hyperbolic tangent torch.nn.Tanh.

  • non_linearity_kwargs (Optional[Mapping[str, Any]]) – If the non_linearity is passed as a class, these keyword arguments are used during its instantiation.

  • entity_initializer (Union[str, Callable[[FloatTensor], FloatTensor], None]) – Entity initializer function. Defaults to torch.nn.init.uniform_()

  • kwargs – Remaining keyword arguments to forward to pykeen.models.EntityEmbeddingModel

Attributes Summary

hpo_default

The default strategy for optimizing the model's hyper-parameters

Attributes Documentation

hpo_default: ClassVar[Mapping[str, Any]] = {'embedding_dim': {'high': 256, 'low': 16, 'q': 16, 'type': <class 'int'>}, 'num_slices': {'high': 4, 'low': 2, 'type': <class 'int'>}}

The default strategy for optimizing the model’s hyper-parameters