A
Sentiment is the standout.
On IMDb, raw zero-shot Jev reaches 96.3%, compared with 88.4% for logistic regression. The +7.9-point advantage remains almost unchanged after threshold adjustment: 96.1% versus 88.3%.
This is the strongest descriptive evidence in Jev’s favor here. The experiment compares a pretrained API model against these classical text pipelines; it does not establish superiority over other language models or stronger modern text representations.
B
Thresholds change the SMS story.
With raw decisions, Jev zero-shot leads Naive Bayes 96.1% to 95.0%. After policy threshold selection, the comparison becomes 95.9% to 96.3%.
The apparent lead becomes a small deficit. A model’s default decision rule and its ability to separate classes are not the same question. Publish both panels; the adjusted Jev result uses labeled policy data.
C
Business tabular tasks remain difficult.
On Bank Marketing, adjusted zero-shot-prompt Jev reaches 59.7%, against the voting ensemble’s 73.3%. On Online Shoppers, even adjusted few-shot Jev reaches only 53.6%, against 71.2%.
Threshold adjustment does not close these gaps. For context, a constant-class prediction scores 50% balanced accuracy on these binary tasks. This is evidence of weak performance on these particular datasets, not a claim about every tabular task.
D
Examples help selectively.
One example per class lifts raw Breast Cancer performance from 61.0% to 88.8%, and Banking77 from 78.9% to 81.9%. But it lowers mean performance on AG News, SMS Spam, IMDb, and Iris.
Breast Cancer also improves to 88.4% using zero-shot prompts with a learned threshold alone. Its raw 61.0% score therefore does not tell the whole story. The holdout is small, and none of these Jev variants reaches the strongest classical result.
One metric, carefully readBalanced accuracy is the average recall across classes. It gives each class equal weight, even when most examples belong to one class. For 77-class Banking77, the constant-class baseline is about 1.3%; for a binary task it is 50%. These are different problems, so we avoid collapsing this suite into one overall score.