# Class 10 analysis worksheet

Names and roles: ____________________

## 1. Calf design and question

The calves keep their allocated diet and are weighed five times. State the outcome and units, diet assignment unit, repeated animal, row meaning, room role and animals or pens assigned to each diet. What changes if diet is assigned to a shared pen?

Translate `room + diet * time_factor + (1 | calf)` into ordinary words. Explain why the baseline diet gap is not a consequence of feeding.

Use the printed week-8 row: estimate ____ kg; approximate interval ____ to ____ kg. What does the interval describe? What sharing between nearby visits might still remain?

## 2. Cow crossover design

Draw AB and BA over two periods. How many cows had a treatment order chosen at random? How many rows are there? Why are those counts different?

Explain period, assigned order, washout and carryover in your own words. Why would all cows receiving A then B be a problem? What scientific evidence would support the treatment-free gap?

## 3. Use the tools and read the results

Which package call fits the model? Which checks it? Which estimates B minus A? Which estimates mean intake under A and B?

Explain each part of `intake_kg_day ~ treatment + period + sequence + (1 | cow)`.

B minus A: estimate ____ kg/day; approximate interval ____ to ____ kg/day. Explain why this is a mean comparison rather than an individual intake range. Name one reassuring check, one limitation and the washout assumption.

Why does adding `sequence` not remove a lingering biological effect? Would a vaccine with a lasting effect be suitable for this simple crossover?

## 4. Project checkpoint — 25 minutes

Save `project-analysis-plan.md` before case fitting or feedback: five minutes map units, eight choose question/model, seven checks/alternative, five save and discuss. Explain the reasons for your choices. Record uncertainty, advice and later changes.

## Individual exit

Correct “48 cow-period rows give 48 separately chosen treatment orders” and “including sequence means washout no longer matters”.