Checklist VsOSh AI 2026 School Stage (Sirius platform, region group 4), grades 9–11 · Task 6
Probability Threshold
Russian title: Задание 6
Apply a 0.6 threshold to predicted probabilities in a table and count correct predictions.
The task
Each row of a table contains a predicted probability p of the positive outcome (0 to 1) and the true label y (1 positive, 0 negative). The prediction is ŷ = 1 if p ≥ 0.6 and 0 otherwise.
Count the rows where ŷ equals y.
Abridged and translated by SOTA from the official Russian materials. The official statement has the exact rules, and it wins wherever this summary differs.
In English
This task was published in Russian. SOTA translated its 3 files into English on 16 September 2026.
- Task statement Russian original of Task statement
- Official solution Russian original of Official solution
- Full paper with solutions (all tasks of the tour) Russian original of Full paper with solutions (all tasks of the tour)
Read the task statement in English
Probability Threshold
English translation by SOTA – AI Community of the Russian original. Organisers who would like this translation removed can email [email protected].
Task 6 of the school stage of the All-Russian School Olympiad (VsOSh) 2025/26 in artificial intelligence (region group IV), grades 9–11. The official answer and solution are in a separate file.
The data for this task are in a spreadsheet file. You can download the file in one of three formats: XLSX, ODS, CSV.
In the document, each row contains two numbers:
- the probability of a positive outcome (a number from 0 to 1);
- the correct label , where is a positive outcome and is a negative one.
Let us define a simple prediction rule:
Problem. Find the number of rows for which the prediction coincides with the correct label .
Scoring criterion: exact match of the numerical answer — 12 points
Maximum score for the task — 12
Translated by SOTA. The Russian original is the official version and wins wherever the two differ. Statement and official solution come from one PDF, the analysis of the school-stage tasks for region group IV, grades 9–11, linked from the olympiad's Sirius page. The data table (XLSX, ODS or CSV) is a separate file that is not part of the published PDF; the spreadsheet formulas are given with English function names. If you organise this olympiad and would like the translation removed, email [email protected] and we will take it down.
At a glance
- You get
- A table (XLSX, ODS or CSV); not included in the published PDF.
- You submit
- One number.
- Scoring
- Exact answer; 12 points.
- Format
- School stage on the Sirius.Courses platform, region group 4, 21 October 2025; grades 9–11; individual; 150 minutes; maximum 112 points for the paper (tasks 1–6: 12 points each; tasks 7–8: 20 points each).