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Michael Nocito5d ago • 14 min read
Excel Tables vs Ranges: What Ctrl+T Actually Changes
One keystroke moves the edges of your data. Structured references, the calculated column that fills ...
#excel#dataanalysis#tutorial#beginners
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Michael Nocito3d ago • 14 min read
Handling Missing Values in pandas: dropna, fillna and What Each One Claims
Seven missing cells cost four rows to dropna and half a column to axis=1. Filling with zero moved th...
#python#pandas#dataanalysis#tutorial
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Michael Nocito3d ago • 13 min read
pandas drop_duplicates: keep='first', and the Row It Chose For You
duplicated and drop_duplicates on the same eight rows: 7, 5 or 2 rows out depending on the arguments...
#python#pandas#dataanalysis#tutorial
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Michael Nocito2d ago • 14 min read
pandas read_csv: Your First DataFrame, and What It Guessed
Four commands to look at a new file, then the arguments that stop read_csv guessing: dtype, parse_da...
#python#pandas#dataanalysis#tutorial
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Michael Nocito2d ago • 13 min read
pandas merge: Left Join, Inner Join, and the One That Doubled the Revenue
The four hows and the row counts they give, indicator to see which side each row came from, and one ...
#python#pandas#dataanalysis#tutorial
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Michael Nocito5d ago • 13 min read
Where to Find Free Datasets to Practice With (And How to Pick One)
Free datasets for data analysis practice: where to get them, the three columns a dataset needs befor...
#dataanalysis#career#tutorial#beginners
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Michael Nocito3d ago • 13 min read
How to Install Python for Data Analysis (And Why pip install Then Fails)
Install Python for data analysis without ending up with three of them. Anaconda or python.org answer...
#python#pandas#dataanalysis#tutorial
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Michael Nocito4d ago • 13 min read
How to Set Up Jupyter Notebook (And Why Your Environment Is Missing From the Kernel List)
Install Jupyter, run your first notebook, and understand the three parts that make it work: browser,...
#python#pandas#dataanalysis#tutorial
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Michael Nocito4d ago • 11 min read
How to Install Power BI Desktop (Including on a Locked-Down Work Laptop)
Install Power BI Desktop free on Windows. The Microsoft Store route needs no admin rights, the direc...
#powerbi#dataanalysis#tutorial#beginners
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Michael NocitoAug 23, 2026 • 14 min read
Excel Dynamic Arrays: FILTER, UNIQUE and SORT in One Formula
One formula, many cells. FILTER, UNIQUE, SORT and SORTBY worked on a real table, the spill reference...
#excel#dataanalysis#tutorial#beginners
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Michael Nocito2d ago • 13 min read
pandas pct_change and cumsum: Percent Change and Running Totals
groupby gave four months and a tidy -6.0%. resample gave five, an empty April at -100%, and an infin...
#python#pandas#dataanalysis#tutorial
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Michael NocitoAug 24, 2026 • 17 min read
INDEX MATCH vs VLOOKUP: The Lookup That Survives a New Column
MATCH finds the position, INDEX fetches the value. Why that beats a hard-coded column number, with a...
#excel#dataanalysis#tutorial#beginners
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Michael NocitoAug 23, 2026 • 14 min read
Excel Drop Down Lists and Data Validation, and the Paste That Removes Them
Build a dropdown in four clicks, put the list somewhere it can grow, and know the gap: an ordinary p...
#excel#dataanalysis#tutorial#beginners
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Michael Nocito4d ago • 11 min read
How to Import a CSV into Power BI (And the Three Dropdowns Nobody Reads)
Import a CSV into Power BI Desktop properly: the File Origin, delimiter and type-detection dropdowns...
#powerbi#dataanalysis#tutorial#beginners
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Michael NocitoAug 23, 2026 • 15 min read
Excel Dates: Serial Numbers, Text That Looks Like a Date, and How to Fix It
A date is the number 46027 wearing a format. How to tell a real date from text in two seconds, three...
#excel#dataanalysis#tutorial#beginners
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Michael Nocito3d ago • 12 min read
How to Install Tableau Public (And Which Free Tableau You Actually Need)
Tableau has two free desktop apps with almost the same name, and only one can publish to your portfo...
#tableau#datavisualization#dataanalysis#tutorial
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Michael Nocito6d ago • 15 min read
Power Query for Beginners: The Steps That Run Again Next Month
Power Query records what you click and replays it on the next file. Getting data in, the Applied Ste...
#excel#dataanalysis#tutorial#beginners
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Michael Nocito6d ago • 13 min read
Month-over-Month Growth in Excel, and the Month That Is Not There
Aggregate to one row per month, then divide. The calendar table that turns a gap into a zero, what t...
#excel#dataanalysis#tutorial#beginners
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Michael Nocito6d ago • 14 min read
Remove Duplicates in Excel Without Losing Data
The columns you tick are the definition of duplicate, and the dialog deletes without telling you wha...
#excel#dataanalysis#tutorial#beginners
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Michael Nocito6d ago • 18 min read
How to Make a Pivot Table, and Read the Answer It Gives You
Four clicks to a summary table, then the parts that decide whether it is right: what Rows and Values...
#excel#dataanalysis#tutorial#beginners
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Michael NocitoAug 23, 2026 • 14 min read
Conditional Formatting Based on Another Cell
One formula rule, one dollar sign, and a whole row lights up from a value in one column. Where the f...
#excel#dataanalysis#tutorial#beginners
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Michael NocitoAug 24, 2026 • 15 min read
How to Use IFERROR in Excel, and What It Quietly Hides
IFERROR catches every error, not just the one you meant. The syntax, the choice between 0 and blank,...
#excel#dataanalysis#tutorial#beginners
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Michael Nocito5d ago • 13 min read
SUMPRODUCT Explained: Multiply Down, Then Add
Pair up two columns, multiply each pair, add the results. The weighted average it exists for, condit...
#excel#dataanalysis#tutorial#beginners
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Michael NocitoAug 24, 2026 • 14 min read
Nested IF vs IFS in Excel: The Order That Silently Relabels Your Data
IFS stops at the first condition that is true, so writing bands in the wrong order moved 3,710 of re...
#excel#dataanalysis#tutorial#beginners
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