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📊 Data
Collect, organize and interpret data. Averages, probability and charts are the basics of understanding the world.
15 topics
- 01📊Mean, Median & ModeThree smart ways to boil a pile of numbers down to one — pick the wrong one for the job and it lies to you.Lesson 1 of 15
- 02🪙Probability for BeginnersA single outcome is unpredictable — but math knows exactly how unpredictable.Lesson 2 of 15
- 03📊Bar GraphsTurn each category's count into a bar, and "who has more" becomes visible at a glance.Lesson 3 of 15
- 04🥧Pie ChartsA circle sliced into a map of shares — each wedge takes its percent of the whole, visible at a glance.Lesson 4 of 15
- 05🎭Misleading GraphsA chart never lies, but the person drawing it picks the angle — learn to spot the classic tricks.Lesson 5 of 15
- 06🌊Range & SpreadThe average can fool you — to know how restless a dataset is, look at how far it scatters.Lesson 6 of 15
- 07📋Surveys & SamplingWhat to ask, whom to ask, how many to ask — every fork in survey design hides a trap.Lesson 7 of 15
- 08📶HistogramsSort continuous data into equal bins, count each one — and the shape of your data appears at a glance.Lesson 8 of 15
- 09✨Scatter Plots & CorrelationPlot two quantities on one grid and the shape of the point cloud tells you how they move together.Lesson 9 of 15
- 10📅Time Series GraphsSort the data by time and connect it into a line — rises, seasonal rhythms, and cherry-picked windows all become visible.Lesson 10 of 15
- 11🌳Compound Probability & Tree DiagramsOne-step probability you can already do — for two steps in a row, multiply along the branches and add between them.Lesson 11 of 15
- 12🧩Venn DiagramsDraw two circles and their overlap is the intersection — the all-purpose way to sort people into sets.Lesson 12 of 15
- 13📉When Averages MisleadAverage salaries that look too high, review scores that look too good — computing an average is step one, spotting its misuse is the real skill.Lesson 13 of 15
- 14🎰Expected ValueA weighted average with probabilities as weights — lotteries, dice and why casinos win in the long run.Lesson 14 of 15
- 15🎲Standard DeviationA second eye beyond the average — two datasets can share a mean while their spread differs tenfold, and standard deviation squeezes that spread into one number.Lesson 15 of 15