DataLeaguebeta

Learn to read data by playing.

Short tasks with instant feedback: multiple choice, a number, Python in the browser or an open question. Points for every correct answer, badges for whole topics.

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48 tasks, 4 lessons, 6 topics and 6 roadmaps from analyst to AI engineer.

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Sample, multiple choice

There are 9 people on a team. The mean salary is €2,300, the median €1,350. What follows from this?

€10,150
Answer options

Pick one option.

A path through every task

Tasks follow the order of topics, the colour of a dot is its topic. The ring shows where to start. Once you sign in, solved dots fill in.

Which variable is interval?A data type is not a scaleDiscrete or continuous?A mean of codesProportion of the answers givenCumulative frequencyClass width by Sturges' ruleBy rows or by columns?Expected frequencyFrequencies and a contingency table in pandasMedian or mean?Calculate the medianThe median from a frequency tableThe mean of two groups combinedMean and median in PythonSalaries by department in pandasThe upper quartileWhat the standard deviation tells usSample standard deviation by handThe upper fence from describe() outputCoefficient of variationWhat a box plot showsWhen the 68, 95 and 99.7 % rule holdsWhat skewness revealsOutliers and shape in pandasShape of the distribution and the typical orderWhich line meets the requirementOutlier, error or exception?What type of question are you asking?Total, or mean per day?Boxes side by sideWhat a conclusion may claimThe four-fold agreement measureAgreement of directions in pandasFormulate a research problemPercentages or percentage pointsMisleading chartCorrelation is not causationFalse positive fraud alertWhat p = 0.03 meansConfident tone, uncertain factExplain an LLM to a colleague from accountingWhat does not belong in a public chatbotReading an ERD and the M:N relationshipWhich normal form is broken?How many rows does a LEFT JOIN return?Customer spend in SQLDesign the tables for a library
  • Descriptive statistics
  • From a chart to a research question
  • Interpreting data
  • Probability and inference
  • AI literacy
  • Databases and SQL

Topics

Every dot is one task. Solve it and it fills with the colour of the topic.

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