The isy-thl/multilingual-e5-base-course-skill-tuned is a finetuned version of the intfloat/multilingual-e5-base model. The primary goal of this finetuning process was to enhance the model's capabilities in information retrieval, specifically for identifying the most relevant skills associated with a given course description in the German language.

Capabilities

Enhanced Skill Retrieval:
- The model excels at identifying and retrieving the most relevant skills for a given course description in German, which can be leveraged for various applications in educational technology.
Multilingual Capability:
- While optimized for German, the underlying base model intfloat/multilingual-e5-base supports multiple languages, making it adaptable for future multilingual finetuning endeavors.
Scalability:
- The model can handle input sequences up to 512 tokens in length, making it suitable for processing comprehensive course descriptions.

Performance

To evaluate the model, all ESCO (x=13895) and GRETA (x=23) skills were embedded using the model under assessment and stored in a vector database. For each query in the evaluation dataset, the top 30 most relevant candidates were retrieved based on cosine similarity. Metrics such as accuracy, precision, recall, NDCG, MRR, and MAP were then calculated. For reranker evaluation, the reranker was used to re-rank the top 30 candidates chosen by the fine-tuned bi-encoder model. The evaluation results were split for the ESCO and GRETA use cases:

ESCO Use Case

GRETA Use Case

The results demonstrate that fine-tuning significantly enhanced the performance of the model, often more than doubling the performance of the non-fine-tuned base model. Notably, fine-tuning with training data from both use cases outperformed fine-tuning with training data from only the target skill taxonomy. This suggests that the models learn more than just specific skills from the training data and are capable of generalizing. Further research could evaluate the model's performance on an unknown skill taxonomy, where we expect it to perform better as well.

The fine-tuned BI-Encoder model (isy-thl/multilingual-e5-base-course-skill-tuned) shows exceptional performance for the target task, providing significant improvements over the base model. To maximize retrieval success, it is recommended to complement the BI-Encoder model with the reranker (isy-thl/bge-reranker-base-course-skill-tuned), especially in scenarios where the computational cost is justified by the need for higher accuracy and precision.

Usage

Sentence Similarity

python

from sentence_transformers import SentenceTransformer
import numpy as np
from sklearn.metrics.pairwise import cosine_similarity

# Download from the 🤗 Hub
model = SentenceTransformer("isy-thl/multilingual-e5-base-course-skill-tuned")
# Run inference
query  = [['query: ','WordPress Grundlagen\n Dieser Kurs vermittelt grundlegende Fähigkeiten zur Erstellung eines Web-Blogs in Wordpress. Sie lernen WordPress zu installieren...']]
corpus = [['passage: ','WordPress'],
          ['passage: ','Website-Wireframe erstellen'],
          ['passage: ','Software für Content-Management-Systeme nutzen']]
query_embeddings = model.encode(query)
corpus_embeddings = model.encode(corpus)
similarities = cosine_similarity(query_embeddings,corpus_embeddings)
retrieved_doc_id = np.argmax(similarities)
print(retrieved_doc_id)

Information Retrieval

First install the langchain and chromadb library:

bash

pip install -U langchain
pip install -U langchain-community
pip install -U chromadb

Then you can load this model, create a vectordatabase and run semantic searches.

python

from langchain_community.embeddings import HuggingFaceBgeEmbeddings
from langchain.vectorstores import Chroma

# Download model and set embed instructions.
embedding = HuggingFaceBgeEmbeddings(
    model_name='isy-thl/multilingual-e5-base-course-skill-tuned',
    query_instruction='query: '',
    embed_instruction='passage: '
)

# Load your documents.
documents = ...

# Create vector database.
db = Chroma.from_documents(
    documents=documents,
    embedding=embedding,
    collection_metadata={'hnsw:space': 'cosine'},
)

# Search database for closest semantic matches.
query = 'WordPress Grundlagen\n Dieser Kurs vermittelt grundlegende Fähigkeiten zur Erstellung eines Web-Blogs in Wordpress. Sie lernen WordPress zu installieren...'
db.similarity_search_with_relevance_scores(query, 20)

Finetuning Details

Finetuning Dataset

The model was finetuned with data from the German Course Competency Alignment Dataset, which includes alignments of course descriptions to the skill taxonomies of ESCO (European Skills, Competences, Qualifications and Occupations) and GRETA (a competency model for professional teaching competencies in adult education). About 100 additional pairs of course descriptions and relevant ESCO-skills from the databases of Kursportal Schleswig-Holstein, and Weiterbildung Hessen eV were used during training but were not allowed to be included in the public dataset.
Best results were achieved during training when the human validated pairs of course descriptions and relevant skills were supplemented with only about 1500 random samples from the ESCO Skill Relations subset. The dataset used during finetuning therefore included about 2000 samples in total.
This dataset was compiled as part of the WISY@KI project, with major contributions from the Institut für Interaktive Systeme at the University of Applied Sciences Lübeck, the Kursportal Schleswig-Holstein, and Weiterbildung Hessen eV. Special thanks to colleagues from MyEduLife and Trainspot.

Finetuning Process

For finetuning the scripts included in the FlagEmbedding repository were used with following enviroment details and training parameters.

Hardware Used:
- Single NVIDIA T4 GPU with 15 GB VRAM.
Duration:
- 2000 data points: ~15 minutes.
Training Parameters:
bash
1torchrun --nproc_per_node 1 \ 2-m FlagEmbedding.baai_general_embedding.finetune.run \ 3--output_dir multilingual_e5_base_finetuned \ 4--model_name_or_path intfloat/multilingual-e5-base \ 5--train_data ./course_competency_alignment_de.jsonl \ 6--learning_rate 1e-5 \ 7--fp16 \ 8--num_train_epochs 5 \ 9--per_device_train_batch_size 4 \ 10--dataloader_drop_last True \ 11--normlized True \ 12--temperature 0.02 \ 13--query_max_len 512 \ 14--passage_max_len 64 \ 15--train_group_size 4 \ 16--negatives_cross_device \ 17--logging_steps 10 \ 18--save_steps 1500 \ 19--query_instruction_for_retrieval ""

Model Details

Model Description

Model Type: Sentence Transformer
Base Model: intfloat/multilingual-e5-base
Maximum Sequence Length: 512 tokens
Output Dimensionality: 768 tokens
Similarity Function: Cosine Similarity
Language: German
License: MIT

Full Model Architecture

SentenceTransformer(
  (0): Transformer({'max_seq_length': 512, 'do_lower_case': False}) with Transformer model: XLMRobertaModel 
  (1): Pooling({'word_embedding_dimension': 768, 'pooling_mode_cls_token': True, 'pooling_mode_mean_tokens': False, 'pooling_mode_max_tokens': False, 'pooling_mode_mean_sqrt_len_tokens': False, 'pooling_mode_weightedmean_tokens': False, 'pooling_mode_lasttoken': False, 'include_prompt': True})
  (2): Normalize()
)

Framework Versions

Python: 3.10.12
Sentence Transformers: 3.0.1
Transformers: 4.41.2
PyTorch: 2.3.0+cu121
Accelerate: 0.32.1
Datasets: 2.20.0
Tokenizers: 0.19.1

Acknowledgments

Special thanks to the contributors from the Institut für Interaktive Systeme, Kursportal Schleswig-Holstein, Weiterbildung Hessen eV, MyEduLife, and Trainspot for their invaluable support and contributions to the dataset and finetuning process.

Funding: This project was funded by the Federal Ministry of Education and Research.

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THL Logo

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Model Card Authors

Pascal Hürten, pascal.huerten@th-luebeck.de