Table 2 Symbol description.

From: Music recommendation algorithms based on knowledge graph and multi-task feature learning

Symbol

Description

u

User

v

Item

M

Number of users

N

Number of items

G

Knowledge graph

(h,r,t)

Three-tuple

h, r, t

Head entity, tail entity, relationship

θ

A parameter of the function f

Y

A user-item interaction matrix

W,\({{\text{W}}}_{{\text{l}}}^{{\text{VV}}}\),\({{\text{W}}}_{{\text{l}}}^{{\text{EV}}}\),\({{\text{W}}}_{{\text{l}}}^{{\text{VE}}}\),\({{\text{W}}}_{{\text{l}}}^{{\text{EE}}}\)

Weight

b,\({{\text{b}}}_{{\text{l}}}^{{\text{V}}}\),\({{\text{b}}}_{{\text{l}}}^{{\text{E}}}\)

Bias

S(v),S(u)

A set of entities associated with music item item v (user u )

\(f_{{R{\text{S}}}}\)

The prediction probability of the recommendation module

\(\alpha ()\)

The tanh function

\(\sigma ()\)

The Sigmoid function

\(\beta ()\)

The softsign function

\(\delta ()\)

The softplus function

\(f_{{{\text{KG}}}}\)

The probability prediction of the KGE module

d

The dimensions of the hidden layer

\({{\text{C}}}_{{\text{l}}}\)

The cross feature matrix of layer l

\({{\text{v}}}_{{\text{l}}+1}\),\({{\text{e}}}_{{\text{l}}+1}\)

Item and entity feature vectors for layer l + 1 after cross-compression unit processing

λ1,λ2

The equilibrium parameters

J

The cross-entropy function