# Synthetic calf-growth fixture

32 individually housed calves in four rooms, eight calves per room. Within each room, four calves are randomly allocated to each of Control and Enhanced feeding. Diet is assigned to **calves**, not rooms. Treatments start after the time-0 measurement. The same calf is weighed at weeks 0, 2, 4, 6 and 8. Researchers assigned 16 calves to each diet, then recorded 160 weights across five visits. All planned observations are present.

| Column | Meaning |
|---|---|
| `room` | Fixed allocation block R1–R4; individual housing within room |
| `calf` | Globally unique calf identifier C01–C32; repeated unit and treatment unit |
| `diet` | Allocated feeding strategy, Control or Enhanced |
| `time_week` | Weeks since start; time 0 is measured before feeding begins |
| `weight_kg` | Synthetic weight in kg, rounded to 0.001 kg for reproducibility |

Teaching assumptions: positive weights around 40 kg at baseline, substantial growth over eight weeks, persistent differences among calves, some slowing with age and possible extra dependence between nearby measurements. These values are biologically transparent illustrative choices, not validated parameter estimates. Rounding precision is computational and does not imply a real scale had gram-level accuracy.

Every calf is individually housed and receives its own diet. Shared room conditions are represented by a fixed room term. A real calf-feeding study may allocate treatments to pens and require a different hierarchy; do not transfer this calf-level replication count automatically.

Origin: generated deterministically for this course, seed 104601. No empirical paper or inaccessible supplement is being represented. The private generation source remains with the instructor. Week 11 uses an identical copy of this fixture.

# Synthetic cow crossover

Twenty-four individually housed cows are randomly assigned to AB or BA, twelve per assigned order. Rations A and B are received in two scheduled ten-day treatment periods. A ten-day treatment-free gap is specified between periods. The outcome is average intake over the final three days of each treatment period, not three separate observations. There are 48 cow-period rows and 24 cows whose treatment order researchers randomly chose. All planned observations are present.

| Column | Meaning |
|---|---|
| `cow` | Unique cow W01–W24; repeated animal |
| `sequence` | Randomly assigned order AB or BA |
| `period` | First or second treatment period, labelled 1 and 2 |
| `treatment` | Ration A or B actually received in that period |
| `intake_kg_day` | Synthetic period-average daily intake, kg/day |

Origin: deterministic course simulation, seed 104602. Values and the ten-day gap are transparent teaching assumptions, not validated biological recommendations. Analysis assumes earlier ration effects no longer influence the recorded later outcome. The outcome data and a sequence term cannot establish that washout is adequate. Real design requires scientific evidence about persistence and subject stability.

Rounding to 0.001 kg/day is for reproducibility and does not claim that a real intake measurement has that accuracy.