Data Analyst

Should a key be created separately in each table?

Tell us about your experience, about a project or task you are proud of.

Compare two versions of an application using key expressions (task: compare the old and new version of YouTube)

What data types can be used as dictionary keys in Python?

What interested you in this vacancy? Did you apply yourself or were you found?

What prompted you to re-enter the job market?

Is there experience working with artificial intelligence? Experience implementing AI in an IT Service Management system?

Middle

СБЕР

What information does preparing a presentation for top management include?

Explain the logic of solving the sum_series problem: how to construct the sum of two stepwise time series?

Intern

Яндекс

Tell us about a typical workday and the volume of communication with the team (considering that the support team is about 10-12 people).

Junior

СБЕР

What programming languages do you know?

Do you know mathematical statistics and have you applied A/B testing in practice? What types of averages do you know?

Middle

МТС

Have you used ranking window functions in your work? If yes, which ones?

How is the final prediction in boosting obtained from three iterations?

Afanasy had been working for 2 weeks on writing code capable of solving Japanese crossword puzzles with support for nine colors, when at a team meeting, a colleague told him that he could handle the task faster himself, and there was no point in the program anymore. But Afanasy, being an optimist, decided to continue practicing this task and do the following — estimate how well his colleague handles crosswords. For this assessment, he chose an analog of the IoU metric — the calculation will be similar to the classic Intersection Over Union, but by colors. It works as follows: each matching cell in the original and the solution by color adds 1 to the numerator, and in the denominator, 1 is added for each cell in the original and the solution (for matching cells, only one is added). After that, averaging is performed over the number of colors in the original image, rounded to two decimal places; zero is not considered a color, so the metric should not be calculated for cells of this color. Input starts with a line containing the number of rows n and columns m (in that order). Then, 2n lines follow, containing m numbers separated by spaces — the first n lines relate to the submitted crossword, and the next n — to the original image. It is assumed that each line, starting from the second, contains exactly m numbers. As an answer, output a number rounded to two decimal places, as in the examples. Here are some examples: 1. First example [phone] -> 1.0 Explanation: the contribution of matching and non-matching cells (1.0 + 1.0 + 1.0 + 1.0) / number of colors (4) 2. Second example [phone] -> 0.08 Explanation: the contribution of matching and non-matching cells (0.25 + 0.0 + 0.0) / number of colors (3); zeros are not counted, neither as cells in representations nor in the number of colors. 3. Third example [phone] where the submitted image starts [phone] — where the submitted image ends 0 1 2 — where the original image begins [phone] -> 0.47 Explanation: the contribution of matching and non-matching cells (0.4 + 0.5 + 0.5) / number of colors (3); zeros are not counted as cells in representations nor in the number of colors. 4. Fourth example [phone] -> 0.0 Explanation: the contribution of matching and non-matching cells (0.0) / number of colors (1); zeros are not counted as cells in representations nor in the number of colors.

Intern

Яндекс

Please tell me what types of logical joins you know.

Provide an example when you initiated changes in DWH, pipeline, or data model yourself.

How to create Report 1 (Balance) — step by step?

How does an LLM work? What is it?

What algorithms for joining two tables (Join) at the physical level do you know?