Compute AVERAGE, MEDIAN, STDEV / STDEV.S, and a simple percentile on a Table column
Use Copilot (or an equivalent assistant) to draft or explain a formula
Verify against a hand-checked example, a boundary, and a type trap
Distinguish allowed assistance from submitting unreviewed generated work
A distribution is more than a mean
The mean is one sentence about a list
AVERAGE of {10, 10, 10, 100} is pulled by 100 (lecture 4)
Median: the middle after sorting — often closer to “a typical row”
Spread: standard deviation, IQR, min/max — “how much do rows disagree?”
A PivotTable of averages by group can hide that one group is tiny (lecture 7)
Science, not vibes
GE Goal 3: a number is a measurement with a method
Report: “median attendance 42 (n = 18); mean 61 because of one festival”
A chart from lecture 5 (histogram or sorted column) is the picture of the same claim
Dropping the festival without saying so is not “cleaning”; it is a different dataset
Statistical functions in Excel
A starter set (Ch. 8)
Question
Function
Note
Typical value
AVERAGE, MEDIAN
Blanks vs zeros (lecture 4)
Spread
STDEV.S (sample), STDEV.P (whole population)
For a class of these students, sample vs population is a judgment
Position
MIN, MAX, QUARTILE.INC / PERCENTILE.INC
Know inclusive vs exclusive if the textbook distinguishes them
Count in a band
COUNTIFS
“How many between 0.7 and 0.8?”
Rank
RANK.EQ
Ties
STDEV.S vs STDEV.P
Sample (S): you have some of the rows, infer spread
Population (P): this list is the whole set you care about
For a single course roster, instructors often treat the roster as the population — say which you used
Copilot may pick .P or .S at random; you choose from the question
Check a tiny list by hand
Data: 2, 4, 4, 4, 5, 5, 7, 9
Median, mean, and a rough sense of spread on paper
Then Excel — if they disagree, your range includes a header or a total row
What Copilot is and is not
A practical definition
Copilot in Microsoft 365 is a language model wired into Excel, Word, PowerPoint, and Outlook
It predicts useful text and formulas from your prompt and (sometimes) the file context
It does not know whether STDEV.S matches your scientific claim
It does not replace SLO5: you determine correctness
Strengths
Remembering syntax (PERCENTILE.INC vs older PERCENTILE)
Explaining a formula you do not yet read fluently
Drafting a caption or data-dictionary stub in Word
Suggesting a PivotTable layout from a stated question
Failure modes you should expect
Invents a column that is not in the sheet
Mixes up relative and absolute references
Treats IDs as numbers, dates as text, or percents as already-multiplied values
Sounds confident while being wrong (fluency ≠ accuracy)
Picks STDEV.P when you meant a sample — or the reverse
Draft, explain, verify
The same loop as every Excel week
flowchart LR
Q[Your question] --> P[Prompt]
P --> D[Draft formula or text]
D --> E[Explain it back in your words]
E --> V[Verify on known rows]
V --> K[Keep, fix, or discard]
If you cannot explain the draft, you do not understand the solution yet
If it fails the known list (2,4,4,4,5,5,7,9), it is not done
Verify like a lab
Keep a known example: tiny list or one student computed by hand
Test a boundary: exact 70%, blank, zero
Test a type trap: ID with a leading zero
Change one input; confirm the output moves in the direction you expect
Prompts that help
Question: median lab score for on-time rows, or STDEV.S of Weighted
Shape: Table name, column headers, types
Success: “Match the paper median of the Checks list; ignore the Totals row”
Weak: “Do stats on this sheet”
Stronger: “Table Scores, column Weighted (numbers 0–1). MEDIAN and STDEV.S of that column only, not the Totals row. Explain sample vs population in one sentence.”
Copilot in Word and PowerPoint
Word: turn the stats into a methods + results paragraph; you still own the numbers
PowerPoint: three slides (question, distribution, caveat) — no invented statistics
Ask Copilot to outline; you paste values from Excel yourself
Academic integrity
Allowed in this course (unless an exam says otherwise)
Using Copilot to learn syntax and to draft formulas you then test
Pasting a generated formula after you can explain it and after it matches your checks
Citing assistance in a brief note when the assignment asks how you worked
Not allowed
Submitting a workbook you cannot explain in office hours
Generating an entire project and turning it in unreviewed
Using Copilot during a closed-resource Excel exam
Presenting Copilot’s prose as your reflection without revision (GE Goal 1a)
Try this in Microsoft 365
Lab 12 — Describe a distribution
On Scores[Weighted], compute n (COUNTA or COUNT), AVERAGE, MEDIAN, MIN, MAX, STDEV.S
Hand-check median on a copy of 7 values in Checks
One-sentence result + caveat in Word (outlier? missing zeros?)
Optional: quartile box or a simple column chart of sorted totals (lecture 5)
Lab 13 — Audit a generated formula
Ask Copilot for nested IF letter grades from Weightedor for a COUNTIFS band
Paste into a new column, not over working formulas
Hand-compute two students and the tiny Checks list
Find at least one bug or ambiguity (boundaries, rounding, Totals row, .P vs .S)
Fix it yourself; comment: what Copilot got wrong
Close the assistant; write the explanation of the fixed formula from memory
Discussion
Designate a note-taker
If Copilot and your hand calculation disagree, which do you trust first?
How is this different from asking a classmate to “just send the file”?
Takeaways
Carry these into Python
Mean, median, and spread are different claims; say which you computed
Copilot is a productivity tool inside the question → check loop
Fluency is not correctness; known rows and boundaries are
Next: when the same Excel steps must run every week, Python repeats a verified analysis