A histogram is a rumor about shape… and the bin width writes the rumor. Too wide and you smooth away the plot twist. Too narrow and everything is noise. Try three bin widths and pick the one that matches the decision you need to make. Name your unit (seconds, points, dollars) and label axes like […]
The Bin Is the Story (Histograms) Read More »
Before the chart, make the table… because a good frequency table is an X-ray. It shows the bones: categories, counts, percents, and a total that actually totals. Sort once for the “what’s most common?” story; sort again for “what should we watch?” Add a percent column to unmask unequal group sizes. If you’re tracking a
Frequency Tables Are First Drafts Read More »
Pie charts are honest only when the parts make a whole and the slices are few. If you have more than five categories, you don’t have a pie; you have a pizza nobody ordered. Use a pie when the message is share of a fixed total (“Which bucket dominates?”). Order slices by size and label
Pies Are for Wholes (and Few Slices) Read More »
A bar chart is a decision in costume. You chose categories, counts (or percents), an order, and a baseline. Each choice nudges the reader toward action. Start by sorting the bars to make the point obvious. If the labels are long, rotate the chart and go horizontal… readability beats tradition. Use percent when group sizes
Bar Charts Make Commitments Read More »
1) Toy Numbers First  Before trusting a formula, feed it toy numbers that make the answer obvious (all 10s, or a single 1 among 0s). If the spreadsheet surprises you there, it’ll betray you later. 2) Sum or Average? Pick the Story  Sum tells you the pile. Average tells you the pace. If you want effort, sum.
Eight Tiny Experiments for Better Formulas & Clearer Conclusions Read More »
Scope of inference has two doors. Random selection answers “Who can we speak about?”… it buys you generalization to the larger population. Random assignment answers “Why did it happen?”… it buys you causal language inside your study. Different keys, different locks. If you have neither, be humble. If you have one, say which door it
Two Keys to Inference: Who and Why Read More »
“Random sample” sounds like a noun, but it’s a choice. Convenience saves time… and buys bias. Stratified sampling protects the small groups you can’t afford to miss. Cluster sampling trades precision for practicality when travel (or time) is the bottleneck. None of these are magic; all of them are honest when you name them. The
Sampling Is a Verb Read More »
Spreadsheets are apprentices. Teach them one clean move and they’ll repeat it perfectly a thousand times. The temptation is to improvise down the column… little tweaks in row 7, a “fix” in row 23. That’s how you lose the plot. Instead, make one formula that tells the truth, copy it through, and let the machine
Teach the Spreadsheet One Move Read More »
Sigma notation looks intimidating until you read it as a story: “Add these, from here to there.” The index is the who. The bounds are the when. The expression is the what. Change any one and you change the story. Summation isn’t “add everything”… it’s “add exactly what matters.” That means choosing the right unit
Σ Is a Highlighter, Not a Hammer Read More »
Formulas are little plays. Parentheses are the stage directions. Without them, the actors guess… and the plot wanders. Most spreadsheet errors aren’t dramatic; they’re quiet: a total a hair too high, an average off by one cell, a minus sign treated like decoration. Order of operations is ruthless about what gets calculated first, so you
Parentheses Are Stage Directions Read More »
