Design pairwise data
Collect or create labelled text pairs with graded similarity or binary same/different labels and reserve a held-out set of pairs for evaluation.
Compute semantic similarity. Inspect similarity scores.
Semantic similarity estimates how close two pieces of text are in meaning, typically using pairwise examples or embedding distances. Important failure modes include paraphrases, negation, domain shift and short noisy inputs; evaluation requires pairwise metrics such as Pearson/Spearman correlation or binary agreement on a similarity threshold.
Learning concept · Not a validated service
Semantic similarity estimates how close two pieces of text are in meaning, typically using pairwise examples or embedding distances. Important failure modes include paraphrases, negation, domain shift and short noisy inputs; evaluation requires pairwise metrics such as Pearson/Spearman correlation or binary agreement on a similarity threshold.
A possible application: deduplicate support tickets by grouping semantically identical reports so agents see consolidated issues. This extension is not implemented by the supplied starter code.
Collect or create labelled text pairs with graded similarity or binary same/different labels and reserve a held-out set of pairs for evaluation.
Compare TF-IDF cosine, pre-trained transformer embeddings, and a supervised scorer trained on pairwise features.
Use correlation for graded scores or precision/recall and AUC for binary same/different tasks, and inspect paraphrase and negation errors.
Wrap the scorer behind an API that accepts two texts, returns a similarity score, and logs inputs for human review and drift monitoring.
The supplied starter code trains a TF-IDF + LogisticRegression classifier on single texts with binary labels, prints a classification report on a tiny synthetic set and shows one sample prediction. It does not accept or score text pairs, compute embedding distances, nor return continuous similarity scores.
model = Pipeline(
steps=[
("tfidf", TfidfVectorizer(ngram_range=(1, 2), min_df=1)),
("classifier", LogisticRegression(max_iter=1000)),
]
)
model.fit(X_train, y_train)
predictions = model.predict(X_test)The code uses single-text classification rather than pairwise similarity scoring: it has no paired inputs, no similarity metric (e.g. cosine on embeddings), and the six hand-written examples are not a labeled similarity dataset, so it cannot validate a semantic-similarity calculator.
Proposed extension: build a pairwise scorer that returns a continuous similarity score using TF-IDF cosine or transformer embeddings, trained and evaluated on a real paraphrase or duplicate-detection dataset.
This is a potential application pathway, not a delivered product. The supplied starter does not implement this service or validate it with real users.
Networkers Home runs this topic inside its AI Engineer Course, with placement support and hands-on labs.