Category: A1; Team name: GAAIMC; Dataset: LastFM Asia

[ixime]

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Description

This pull request adds the LastFM Asia Dataset published in [1] for TAG-DS Topological Deep Learning Challenge 2025: expanding the data landscape.

This dataset contains a social network of LastFM users which was collected from the public API in March 2020. Nodes are LastFM users from Asian countries and edges are mutual follower relationships between them. The vertex features are extracted based on the artists liked by the users. The task related to the graph is multinomial node classification - one has to predict the location of users. This target feature was derived from the country field for each user. [2]

This dataset was shared in PyG [3], but the url to download it is broken, so we downloaded it from [2]. In [4] the features were truncated to a dimensionality of 128 using SVD. We added the dimensionality reduction as a data transformation and is performed as default for this dataset, however the complete data is kept, in case of choosing another kind of data transformation.

The same data transformation is used in PR's #214, #217 and #229

References:

[1] B. Rozemberczki and R. Sarkar. Characteristic Functions on Graphs: Birds of a Feather, from Statistical Descriptors to Parametric Models. 2020.
[2] SNAP: Network Datasets: LastFM Asia
[3] LastFM Asia in PyG
[4] B. Rozemberczki and R. Sarkar. Characteristic Functions on Graphs: Birds of a Feather, from Statistical Descriptors to Parametric Models. 2020.

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