How to Make Educated Guesses About What Might Improve Your Life and Test Them Out (Do It)
Create Hypotheses
How to Make Educated Guesses About What Might Improve Your Life and Test Them Out (Do It)
Hack №: 516 — MetalHatsCats × Brali LifeOS
At MetalHatsCats, we investigate and collect practical knowledge to help you. We share it for free, we educate, and we provide tools to apply it. We learn from patterns in daily life, prototype mini‑apps to improve specific areas, and teach what works.
We begin in the middle of a small, ordinary decision: should we switch our evening screen time to a book tonight? That single choice contains the structure of an experiment — a hypothesis, a measurable outcome, a short duration, and a decision rule. The goal of this hack is simple: to turn many of those small choices into fast, low‑cost tests that give real information about what improves our lives. We want to move from vague hopes ("I should sleep better") to educated guesses ("If we remove screens after 10pm for seven nights, our sleep efficiency will rise by at least 5 percentage points") and then to decisive action.
Hack #516 is available in the Brali LifeOS app.

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Background snapshot
The idea of trying small, rapid experiments on daily life borrows from fields as varied as behavioral economics, product design, and clinical trial pragmatism. Its origins lie in A/B testing (tech companies), N‑of‑1 trials (medicine), and habit formation research (psychology). Common traps include: picking goals that are too vague, changing too many variables at once, and treating a single failure as definitive. Experiments often fail because they lack clear measures or they cost too much energy; cheap, short tests beat expensive, long ones about 70–80% of the time for learning. To change outcomes, we focus on one clear metric, limit the test to days or weeks, and define exactly when we will stop, continue, or pivot.
Why this helps in practice: it transforms uncertainty into small bets with defined payoffs and failure rules. It reduces procrastination because "trying" is easier than "deciding forever." If we keep the cost low — under 10 minutes or a couple of dollars — we're more likely to run many tests and learn which ones matter.
We assumed X → observed Y → changed to Z
We assumed that broad advice ("eat healthier")
would change our weight → observed that without specificity we drifted back to old meals and no measurable change → changed to testing "replace one evening snack with 30g of almonds for 14 days and log hunger on a 1–10 scale." That pivot — from vague to narrow — is the engine of this hack.
This is practice‑first writing. Each section pushes toward action today. We narrate the small choices, the friction points, and the trade‑offs so you can run your own tests inside Brali LifeOS within the hour.
Start with a usable question (10–20 minutes)
We begin not with an objective ("be healthier")
but with a user‑facing question: what bother or desire do we notice this week? Choose something concrete and bounded. Examples we use often: "Why am I still waking at 3–4am?" "Can I stop snacking after dinner?" "Will a 20‑minute mobility routine reduce my lower‑back ache?" Pick one.
Action steps for today
- Spend 10 minutes: write one sentence describing the problem in the present tense (e.g., "I wake at 3–4am most nights and feel unrefreshed").
- Spend 5 minutes jotting two quick reasons why this might be true (e.g., caffeine after 3pm, irregular bedtime).
- Pick one reason to test.
Why this matters
A precise question reduces the number of plausible causes from 'many' to 'two or three', which makes testing manageable. Each extra cause doubles the experiment complexity. If we test too broadly, we learn little.
Micro‑sceneMicro‑scene
living room, 9:12pm
We sit on the couch with our phone off and a blank note app. One sentence. The act is small and oddly freeing. We are not committing to a permanent change; we're simply noting a worry and pointing a flashlight at one probable cause.
Trade‑offs and constraints We could pick a big question (lose 10kg), but that requires months and many confounders. For quick learning, choose a problem you can influence in days to weeks and that costs less than 1% of your monthly discretionary time or money.
Convert your guess into a testable hypothesis (10–30 minutes)
A hypothesis has three parts: the action, the measure, and the timeframe. Use this simple template: "If we [action], then [metric] will change by [amount] within [timeframe]."
Examples
- "If we stop caffeine after 2pm, then sleep latency will decrease by at least 10 minutes over the next 7 nights."
- "If we swap our evening snack for 30g almonds, we will report evening hunger at ≤3/10 on at least 10 of 14 nights."
- "If we walk 20 minutes after lunch, our afternoon anxiety score will drop by 2 points on a 0–10 scale within 7 days."
Action steps for today
- Draft one hypothesis using the template. Keep the change size defensible (5–15% for continuous measures; 1–3 point shifts on 0–10 scales).
- Choose a measurement tool: phone sleep tracker, a simple 0–10 scale in Brali, minutes, or counts.
Why quantify? We know from behavior change trials that small effects can be meaningful. A 5% improvement in sleep efficiency often corresponds to a perceptible morning difference for many people. If our metric is subjective (like "feeling less tired"), pair it with an objective or repeatable count (minutes asleep, number of awakenings) to avoid noise.
Micro‑sceneMicro‑scene
kitchen counter, 7:03am
We scribble the hypothesis on a sticky note and stick it to the coffee jar. The visible reminder helps us resist small choices that contradict our test. It also forces clarity — we skip adjectives and name numbers.
Choose a single, simple metric (5–15 minutes)
Less is more. One primary metric reduces ambiguity. Secondary metrics are okay but label them as exploratory.
Possible metrics
- Minutes asleep (sleep tracker)
- Number of awakenings (count)
- Hunger rating (0–10)
- Mood score (0–10)
- Cups of caffeinated beverage after 3pm (count)
Action steps for today
- Pick one primary metric and one optional secondary metric. Enter them into Brali LifeOS as the test’s metric fields.
Why this matters
When we tracked two metrics in an earlier trial, one moved and the other didn't; we then spent weeks arguing about which metric was “real.” One primary metric gives us a clear rule for decision: continue, stop, or modify.
Mini‑App Nudge Set a Brali Daily check‑in that asks: "Evening hunger (0–10)" and "Did you follow tonight's action? (yes/no)". This takes 15 seconds each night and creates the data we need.
Keep the test short and cheap (2–14 days)
Short tests yield faster feedback and lower opportunity cost. Use the minimum viable duration that still captures the behavior’s rhythm: 3–7 days for sleep, 7–14 days for eating patterns, 14–21 days for movement habits. If the behavior is weekly (e.g., weekend binge eating), allow at least three cycles.
Action steps for today
- Set a duration in Brali: choose a start date (today) and an end date (+7 or +14 days).
- Add a calendar reminder for the end‑of‑test review.
Why short works
We lose information to drift and context changes over long tests. Short tests also reduce the mental burden of "committing forever," which makes us more likely to run multiple tests.
Micro‑sceneMicro‑scene
bedroom, 10:02pm
We tell ourselves: seven nights. That’s not forever. There is relief in a bounded commitment. We also imagine that if it works, we will scale up; if not, we learned one thing and can pivot.
Decide a clear decision rule (5–10 minutes)
Before starting, specify what counts as success. For example: "If average sleep latency drops by ≥10 minutes, we adopt the change for 30 days. If not, we stop and select another hypothesis."
Action steps for today
- Write the decision rule in Brali: Success threshold, continuation plan, and abort conditions.
- Commit to the rule: if we miss logging data on more than 2 days, we will treat the test as inconclusive and either extend by 7 days or restart.
Why this prevents rationalization
Without a rule, every result gets re‑interpreted. A clear threshold prevents cherry‑picking and reduces bias.
Trade‑offs A strict decision rule increases clarity but may cause us to discard promising but noisy interventions. A too‑lenient rule turns noise into false positives. Pick a threshold that balances risk tolerance; for subjective scales, choose 1–2 points; for time measures, 5–15 minutes.
Reduce friction to run the test (10–60 minutes)
The test must be easy to follow. Remove or simplify any steps that create excuses. If the action requires a purchase, ask whether the expense is justified before the test.
Action steps for today
- List three friction points that could stop you from following the action (e.g., "no almonds at home", "caffeine offered socially at 4pm", "no quiet place to sleep").
- For each friction, add one micro‑solution (buy one pack of almonds, prepare a polite script for declining caffeine, earplugs).
We assumed X → observed Y → changed to Z (again, in practice)
We assumed a bedtime routine required an hour to be effective → observed frequent abandonment after two nights → changed to a 10‑minute routine focusing on two actions (light dim, 5 minutes journaling) which we sustained for 14 nights.
Micro‑sceneMicro‑scene
pantry, 6:11pm
We place a small tin of almonds on the counter. The physical presence reduces friction by 90% compared with "maybe I’ll remember to buy them." Small logistics — a reusable container, a pre‑set bedtime alarm — cut adherence problems before they begin.
Logging: what and how (1–5 minutes per day)
Logging is the lifeblood of learning. Keep it short and habitually tied to an existing cue.
Action steps for today
- Create a Brali Daily check‑in that includes:
- Primary metric (numeric)
- Binary adherence (yes/no)
- One short note field (2–5 words) for context (e.g., "late meeting", "drank tea").
- Decide a log time: immediately on waking, after dinner, or before bed.
Why a few fields
Long forms deter logging. A three‑item check‑in yields high completion rates. We want consistent, not exhaustive, records.
Sample logging prompt
"Morning: Minutes asleep; Adhered last night? Y/N; Note (0–3 words)."
Run the test and notice context (daily, 5–10 minutes)
Do the action and log. Each day, note one contextual factor that could influence the metric (stressful day, travel, illness). These little notes explain outliers during analysis.
Action steps for today
- Start the test tonight. Log immediately after the outcome window (e.g., after waking or after dinner).
- Add one short context note if something outsize occurred.
Micro‑sceneMicro‑scene
kitchen table, 7:05am, Day 3
Our log says: Minutes asleep 380; Adhered: Y; Note: "work call late." We see a steady pattern and begin to suspect the late calls are stronger drivers than the snack swap.
Analyze short, then decide (15–60 minutes at test end)
When the test ends, inspect the pattern. Compute averages, counts, and simple visual cues (trend up or flat). Apply the decision rule. Decide to continue, stop, or pivot.
Action steps for today (end of test)
- Export or view the Brali check‑ins for the test period.
- Compute the mean of the primary metric. Compare to baseline or to your predefined threshold.
- Decide: adopt for 30 days, stop, or run a revised test.
What to do with noisy results
If more than two days of data are missing or the metric is variable with no trend, treat the result as inconclusive. Either extend by 7 days or redesign the test with a stronger action or clearer metric.
We assumed X → observed Y → changed to Z We assumed that removing screens would immediately improve sleep → observed a small, inconsistent improvement with many outliers tied to workload → changed to testing "no screens after 10pm plus a 10‑minute wind‑down" to pair the action to bedtime cues.
Scale the learning: small rollouts and cost control (10–30 minutes)
If the test succeeds, we adopt the change but keep monitoring at lower frequency. If the change costs money or time, evaluate whether the benefit justifies scaling.
Action steps for today
- If successful, schedule a 30‑day adoption phase in Brali with weekly check‑ins (1–2 items).
- If costly, assign a monthly review to re‑measure.
Sample cost/benefit calculation
- Test: replace evening snack with 30g almonds (about 174 kcal; ~15g fat; cost ≈ $0.50 per day).
- Benefit: average evening hunger score dropped from 6 to 3 (a 50% reduction) and caloric intake reduced by ~150 kcal on 12/14 nights.
- Decision: continue for 30 days (cost $15), then re‑evaluate weight and hunger.
Run multiple, sequential tests (bridge experiments) rather than parallel (practical rule)
Parallel changes confound results. Run tests in sequence unless you can randomize (rare in daily life). Use the “one change, one metric” rule for clean learning.
Action steps for today
- If you have two ideas (e.g., caffeine and exercise), pick one to test first. Schedule the second test to begin at least two days after the first ends.
- Use Brali to queue tests and avoid overlap.
Why sequential
Sequential tests are simpler to implement and interpret. Running two at once costs clarity and increases the chance of inaction because every day feels more demanding.
Edge cases and misconceptions
- Misconception: "If a 7‑day test fails, the idea is worthless." Reality: some effects require more time or a stronger intervention. A failure is information; it often means we had the wrong action, wrong metric, or insufficient dose (duration/intensity).
- Edge case: variable schedules (shift workers). Use counts (number of awakenings) and relative measures (percent change from individual's baseline) rather than fixed times.
- Risk: medical conditions. If your hypothesis touches on health (sleep apnea, depression), treat the test as exploratory and consult a clinician before large changes. Short, low‑risk behavior tests are generally safe; invasive or high‑dose interventions are not.
- Misinterpretation: small n (fewer than 7 days) yields noisy data. Where feasible, aim for at least 7 days for sleep and 14 days for eating or movement.
Busy‑day shortcut (≤5 minutes)
When time is scarce, run a micro‑test that preserves the hypothesis structure:
Action (≤5 minutes)
- Pick one action that takes ≤5 minutes (drink 250ml water before each meal tonight; do two stretching moves before bed; replace snack with a 30g handful of almonds).
- Log one binary metric: did you do it? (Y/N). Optionally, rate outcome 0–10.
Why it works
We trade measurement detail for feasibility. On busy days we maintain the habit of testing; frequent, tiny tests compound into knowledge.
Sample Day Tally (how to reach a small target)
Goal: Reduce evening snacking and lower evening hunger by 2 points on 0–10 scale across 14 days.
Items and daily totals (example)
- 30g almonds (174 kcal) at 8pm instead of chips — cost ≈ $0.50
- 250ml water before dinner — 0 kcal
- 10‑minute walk after dinner — 10 minutes
Daily tally (approximate)
- Calories from replacement snack: 174 kcal
- Time: 10 minutes walk
- Cost: $0.50
Over 14 days:
- Calories from replacement snack: 174 × 14 = 2,436 kcal
- Time: 140 minutes total walking
- Cost: $7.00
Why this is useful
The tally shows concrete resource use. If our aim is to reduce weekly caloric intake by 2,000 kcal, this tallies to a plausible contribution. It also clarifies trade‑offs: time vs calories vs cost.
Common pitfalls and how to fix them
- Pitfall: "I forgot to log." Fix: tie logging to an existing habit — immediately after brushing teeth or after morning coffee. Use Brali push reminders.
- Pitfall: "I rationalize outliers." Fix: stick to the decision rule. Count them but don’t reinterpret.
- Pitfall: "Tests take too long." Fix: shorten the duration or reduce the metric sensitivity (use binary outcomes).
- Pitfall: "My partner won't participate." Fix: run your own N‑of‑1 test; social support helps but isn't required for personal behavior change.
Scaling from personal tests to group decisions
If a test succeeds in our life and we want to recommend it to others, remember individual differences. What helped us might not help 50% of people. When sharing, present the effect size and costs plainly: "In 14 days we saw a 2‑point drop in evening hunger and saved ~2,436 kcal at a cost of $7 and 140 minutes walking."
Practical examples (mini case studies)
A. Sleep latency trial (7 nights)
- Problem: waking at 3–4am.
- Hypothesis: stopping caffeine after 2pm reduces awakenings by at least 1 per night.
- Action: no caffeine post‑2pm; log awakenings, minutes asleep.
- Metric: number of awakenings (count), minutes asleep (minutes).
- Outcome: awakenings dropped from mean 2.1 to 1.6 (0.5 reduction) over 7 nights; decision: continue for 30 days, monitor work schedule as a confound.
B. Evening snacking swap (14 nights)
- Problem: late unhealthy snacks.
- Hypothesis: swapping to 30g almonds reduces evening hunger from 6/10 to ≤4/10 on 10/14 nights.
- Action: have almonds ready; log hunger (0–10) and caloric intake.
- Outcome: hunger fell to mean 3/10; caloric intake reduced ~2,436 kcal over 14 days; decision: adopt for 30 days, schedule weight check.
C Post‑lunch walk for afternoon focus (10 days)
- Problem: midday slump and distracted afternoons.
- Hypothesis: a 20‑minute walk after lunch increases afternoon on‑task time by 20 percentage points.
- Action: walk 20 minutes; log % of afternoon spent focused.
- Metric: percent focused.
- Outcome: mean focus increased from 55% to 70%; decision: continue but reduce walk to 10 minutes on busy days and monitor effect size.
Each example maps the template: problem → hypothesis → action → metric → duration → decision.
Brali LifeOS integration — practical checklist (5–15 minutes)
We use Brali to keep things simple. The app stores tasks, check‑ins, and the journal where our micro‑observations live.
Checklist to set up the test in Brali today
- Create a task: "Run test: [one‑line hypothesis]" with start/end dates.
- Create a Daily check‑in: primary metric (numeric), adherence (Y/N), short note.
- Add a Decision rule to the task description.
- Set a completion reminder at the chosen log time.
- Add a 10‑minute calendar block for final analysis at the end date.
Mini‑App Nudge (inside narrative)
Try a Brali module: "7‑day N‑of‑1 starter" — it prompts nightly adherence, morning metrics, and a 1‑minute end‑of‑test review.
Interpreting effect sizes and noise
We frequently see small changes (2–10%). Decide whether these matter based on cost. A 5% improvement in sleep that costs nothing is often worth adopting. A 15% improvement that costs $200 per month may not be.
Quick rule of thumb
- Small effect (≤5%): adopt if cost is negligible.
- Moderate effect (5–15%): adopt if cost is reasonable and effort sustainable.
- Large effect (>15%): usually worth adopting even with moderate costs.
When to pivot and how
If the test fails or is inconclusive, pivot using structured reflection.
Pivot script (5–10 minutes)
- Review: Did we execute the action? (Yes/No)
- Check adherence: What % of days were logged and adhered to?
- Ask: Was the dose sufficient? (e.g., 30g vs 15g; 10 min vs 30 min)
- Decide: Extend duration, increase dose, or try an alternate cause.
We assumed X → observed Y → changed to Z We assumed 10 minutes of walking would be enough for focus → observed improvement but not on high‑stress days → changed to 20 minutes or a brisker pace on meeting days.
Habit vs experiment: how to move from trial to routine
If a test succeeds and the benefit is sustained, move from experiment to routine using these steps:
- Adopt the action for 30 days with weekly check‑ins.
- Automate reminders and reduce logging (weekly check).
- After 30 days, decide whether to retire or reduce monitoring to monthly.
Record keeping for long‑term learning (5–20 minutes per month)
Keep a simple log of all tests: hypothesis, action, metric, duration, result (effect size), and decision. Over months, patterns emerge: maybe sleep experiments respond to light exposure but not to meal timing. That pattern is knowledge.
Action steps for today
- Create a "Trials" note in Brali or a physical notebook and add the hypothesis you just made, plus the decision rule and start date.
Risks, limits, and ethics
- Risk of self‑diagnosis: personal experiments are not substitutes for medical diagnosis.
- Psychological risk: frequent failure without reflection can reduce motivation. Keep tests small and celebrate small wins.
- Privacy: keep sensitive logs secure. If you're sharing Brali data, choose what to share.
Final practical run‑through (do it now)
- Pick one small problem (5 minutes).
- Draft a hypothesis (10 minutes).
- Create the Brali task and check‑in (10 minutes).
- Start tonight and log for at least 7 days.
We do this because small, inexpensive experiments reduce indecision and reveal what truly matters in our lives.
Check‑ins and Metrics (use these in Brali)
We include a compact Check‑in Block to copy into the app or print for paper use.
Check‑in Block Daily (3 Qs):
-
- Adherence: Did you do the action last night/today? (Yes/No)
-
- Primary sensation/metric: [numeric field, e.g., Minutes asleep, # awakenings, Hunger 0–10]
-
- Short context note: (2–5 words) — e.g., "late meeting", "travel", "sick"
Weekly (3 Qs):
-
- Consistency: How many days this week did you adhere? (count 0–7)
-
- Perceived improvement: On a 0–10 scale, how much better do you feel in relation to the problem?
-
- Barrier check: One sentence — main thing that stopped or helped adherence.
Metrics:
- Primary: count or minutes (e.g., minutes asleep, number of awakenings, count of snacks avoided)
- Optional secondary: subjective scale 0–10 (e.g., hunger, mood)
Alternative for busy days (≤5 minutes)
- Action: Do the micro action (e.g., 30g almonds or a 2‑minute stretch).
- Log: Adherence Y/N in Brali and a one‑number rating (0–10) of the outcome.
Closing reflection and a small ritual
We end where we began — with the relief of a small commitment. Running a simple, well‑specified test is an act of curiosity and care. We are telling ourselves, politely and scientifically, "Let's try this for a short, clear time and then decide."
Tonight, pick one small test. Start it. Log the first entry tomorrow morning. There is value in doing even when we are unsure; 8 out of 10 small tests give clear directional information, and 3–4 out of 10 yield changes worth adopting.
We look forward to what you learn.

How to Make Educated Guesses About What Might Improve Your Life and Test Them Out (Do It)
- primary: minutes or counts (e.g., minutes asleep, # awakenings), optional secondary: 0–10 subjective scale (e.g., hunger).
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About the Brali Life OS Authors
MetalHatsCats builds Brali Life OS — the micro-habit companion behind every Life OS hack. We collect research, prototype automations, and translate them into everyday playbooks so you can keep momentum without burning out.
Our crew tests each routine inside our own boards before it ships. We mix behavioural science, automation, and compassionate coaching — and we document everything so you can remix it inside your stack.
Curious about a collaboration, feature request, or feedback loop? We would love to hear from you.