The household task
Choose an observation you can repeat. A useful trial asks whether the same person can read the same page from the same chair with acceptable glareDiscomfort or impaired viewing caused by bright light directly or through reflection.
Example: A glossy page shows a distracting reflected patch..
Record the old bulb, lamp position and operating schedule before changing them. A household electricity bill includes many other loads; a small lighting change is hard to isolate from that total.
Compare the lighting task directly and estimate its energy separately. Do not turn a comfort judgment into an invented laboratory measurement. If you use a simple yes/no check, state who judged it and under what conditions.
Try the supplied case
Before the trial, Cedar reports a shadow across the page, an annoying screen reflection and a 7 to 10 p.m. reading schedule. No light meter readings are available.
Write three acceptance checks and one comparison condition in the goal section.
One defensible response
Accept if the page is comfortably readable, the television reflection is no longer distracting and the trial purchase is at most $20. Compare from the same chair after dark using the same page.
These checks can be repeated with the available evidence. A precise lux improvement would require measurements that this case does not supply.
Check your response: Use observable judgments and preserve at least one comparison condition; do not invent a measured lux value.
You now have a task and a first room. Next, learn the package numbers that let you buy light for that task.