What’s on the Data Cleaning poster?

5 numbered steps, with a full worked run-through. In roughly this order — each step can change what the next one finds. Check the shape — Row count, column count, types. Does it match what you expected?; Find the missing — How many nulls per column, and whether they are random or patterned.; Check ranges — Min, max and distribution per column. Negative ages, dates in 1900, im…; Find duplicates — Exact and near-duplicates. Decide which copy is authoritative.; Standardise — Dates, units, casing, whitespace, encodings, categories that mean the s…. Missing not at random is the dangerous case: if the missingness correlates with the outcome, dropping rows biases the result.

Who is the Data Cleaning poster for?

Data Cleaning belongs to the Computing section rather than to a school year, because computing is not something one grade owns. Anyone learning data can pin it up — a beginner, a student mid-course, or someone revising years later.

When should you use the Data Cleaning poster?

Spend the first hour on the data, not the analysis. Every hour here saves several later. A wall chart earns its place by being glanceable from where the work is happening, so Data Cleaning belongs on the wall where that computing work actually happens, within glancing distance, rather than filed away.

What other posters go with Data Cleaning?

ACID, The CAP Theorem and Choosing a Chart sit alongside Data Cleaning in the Computing section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.

Is the Data Cleaning poster free to download and print?

Yes. Data Cleaning downloads as a free PDF with no account, no email and no watermark, like everything else in the Computing section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.

What size does the Data Cleaning poster print at?

Data Cleaning is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of Data Cleaning loses nothing.

Data Cleaning — free printable poster

Data Cleaning — printable computing wall chart from LearnPosters. Free vector PDF, US Letter and A4.

Data Cleaning, step by step

In roughly this order — each step can change what the next one finds.

Check the shapeRow count, column count, types. Does it match what you expected?
Find the missingHow many nulls per column, and whether they are random or patterned.
Check rangesMin, max and distribution per column. Negative ages, dates in 1900, impossible values.
Find duplicatesExact and near-duplicates. Decide which copy is authoritative.
StandardiseDates, units, casing, whitespace, encodings, categories that mean the same thing.

Missing data options

Drop the rows — only if they are few and random
Impute — with the median, or a model
Flag it — add an is_missing column

Missing not at random is the dangerous case: if the missingness correlates with the outcome, dropping rows biases the result.

Questions about the Data Cleaning poster

What’s on the Data Cleaning poster?: 5 numbered steps, with a full worked run-through. In roughly this order — each step can change what the next one finds. Check the shape — Row count, column count, types. Does it match what you expected?; Find the missing — How many nulls per column, and whether they are random or patterned.; Check ranges — Min, max and distribution per column. Negative ages, dates in 1900, im…; Find duplicates — Exact and near-duplicates. Decide which copy is authoritative.; Standardise — Dates, units, casing, whitespace, encodings, categories that mean the s…. Missing not at random is the dangerous case: if the missingness correlates with the outcome, dropping rows biases the result.
Who is the Data Cleaning poster for?: Data Cleaning belongs to the Computing section rather than to a school year, because computing is not something one grade owns. Anyone learning data can pin it up — a beginner, a student mid-course, or someone revising years later.
When should you use the Data Cleaning poster?: Spend the first hour on the data, not the analysis. Every hour here saves several later. A wall chart earns its place by being glanceable from where the work is happening, so Data Cleaning belongs on the wall where that computing work actually happens, within glancing distance, rather than filed away.
What other posters go with Data Cleaning?: ACID, The CAP Theorem and Choosing a Chart sit alongside Data Cleaning in the Computing section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.ACID The CAP Theorem Choosing a Chart
Is the Data Cleaning poster free to download and print?: Yes. Data Cleaning downloads as a free PDF with no account, no email and no watermark, like everything else in the Computing section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
What size does the Data Cleaning poster print at?: Data Cleaning is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of Data Cleaning loses nothing.Printing guide

Data Cleaning, step by step

Questions about the Data Cleaning poster

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