Two-state readout starts by assigning calibrated low and high signal levels to prepared zero and one cases. The levels are exact only for the declared toy calibration and fixed threshold; real readout chains add gain drift, amplifier noise, state-preparation error, relaxation during measurement, and calibration uncertainty.
A two-state readout starts with exact low and high signal levels. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Prepared zero has a low signal
The calibrated zero signal is 2, below the threshold 5.
s0=2,T=5
Prepared one has a high signal
The calibrated one signal is 8, above the same threshold 5.