Thu, Mar 11, 2027Spring (Semester 2) · Week 8Day 29 of 6180-min blockCalendar fit

Bias, error, graph choice

Essential question: How do you show a pattern in data honestly, so the graph reveals what happened instead of hiding or exaggerating it?Enduring understanding: The graph you choose is an argument. The right graph lets a real difference speak for itself, and naming the bias and error in your own study is what separates a scientist from a salesperson.

Safety gate · before any work

  • Wear the required PPE, keep the bench clear, handle equipment only as directed, and know where the eyewash, sink, and spill kit are before you start.
  • Human samples and data stay private: label with a code, never a name, and dispose of materials in the correct waste container, then wash your hands.

Do now

Identify sources of bias and error and choose the right graph for your physiology data.

DueTonight, 11:29 PM
Hand in
Draft graph showing the physiology comparison with labeled axes, units, a title, and an annotated bias-and-error note.
Where
Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.

You get two school days for every day you were absent, so this deadline moves with you.

Where you are · this course
Bias, error, graph choice, CER conclusion, limitations. Bias, error, graph choice ▸ Day 2
Day 29 of 61 this semester32 left before WebXam
🧬 Where you are · PLTW
Biomedical InnovationProblem 2: Exploring Human Physiology"Activity 2.1.3 Making Results Meaningful"
Matched to your live myPLTW course (verified June 2026).
Today's driving question

You measured two conditions (say resting versus post-exercise heart rate). Which graph makes the real difference between them visible, and what bias in how you collected the data could be faking that difference?

Today you'll be able to

Identify sources of bias and error and choose the right graph for your physiology data.

You've got it when
  • You can name specific bias and error sources in your study.
  • You can justify your graph choice for the comparison.
Due today · Data table RequiredDraft graph showing the physiology comparison with labeled axes, units, a title, and an annotated bias-and-error note.
Do-Now · start these with your notes closed
  1. Your study compares two conditions. Should the axis that shows your measured values start at zero, and why does that choice change what the reader sees?
  2. Name one way the order you tested people (who went first, who was tired) could have nudged your numbers in one direction.
Do this · step by step
numbered so we can always find our place
  1. 1List possible sources of bias and measurement error in your study.
  2. 2Decide which graph type best shows your comparison.
  3. 3Draft the graph with labeled axes and units.
  4. 4Note how bias or error could affect what the graph shows.
  5. 5Submit your graph draft with a bias-and-error note.
Interrupted or lost? Pick up where you stopped: if you have not listed bias and error sources yet, start there; if you have that list but no graph, decide your graph type and draft it with labeled axes and units; if the graph is drawn, add the note explaining how bias or error could shift what it shows, then submit.
Optional project open: Microbiology & the Working Lab - solo or group, about 3 to 4 hours total. Due by Fri, May 28, 2027. Great WebXam prep.
The story

What did this day actually feel like?

Bias, error, graph choice

How the same honest data becomes a different claim depending on axis range, bar versus line, and what you leave out.

He showed us a graph with a truncated y-axis that made a tiny difference look enormous, then the same data drawn properly. Nobody lied and the two pictures say opposite things.

Turned in: data table → Data Tables folder

Fiction. There is no such student. The lessons, labs and dates are the real planned course; the student, the classmates and the conversations are invented.

The comic

The same day, drawn.

Drawing, panel 38: Bias, error, graph choice.

How the same honest data becomes a different claim depending on axis range, bar versus line, and what you leave out.

Panel 38Bias, error, graph choice · 2027-03-11
Read week 8, 4 panels

Fiction. There is no such student. The lessons, labs and dates are the real planned course; the student, the classmates and the conversations are invented.

🛠 Get unstuck · pick your level

Run the lab
Run the choice for your real data: pick the graph type that fits a two-condition comparison, draw it with labeled axes and units starting at a fair baseline, then write one honest sentence about a bias or error source that could distort it.
Absent? Async catch-up
Absent today? Take your two columns of data, build one correctly labeled comparison graph in a spreadsheet, and write a two-line note naming one bias and one measurement-error source, then upload it to catch up.

Lab day: Tier 1 is the whole class at the bench. No extension today.

🔑 Today's words · 5

biaslimitationreplicationstatistical significanceevidence

Tap a word in the lesson for a plain meaning and one example. Recycled into next week's Do-Now.

Today's study notebook
Turning raw measurements into claims: graphs, mean and standard deviation, and reading a dataset.
Open the notebook
Watch first: today's 1-minute intro
Audio overviewVideo overviewMind mapStudy guideFlashcardsQuizData table
Where this fits
Tested on (Ohio WebXam)
Biotechnology for Health and Disease · 072125 (likely, pending confirmation)
PLTW lesson
BI · Problem 2: Exploring Human Physiology
WebXam domain
Microbiology Testing and Technology
Evidence to produce
Data table
Lab / skill
Khan Academy Statistics and Probability
Do the work · 80-minute blockfirst 5 min = hook

💡 Big idea: The graph type encodes a claim about your data, so choosing one that fits a two-condition comparison (and starting the axis fairly) is what lets the real pattern show instead of a manufactured one.

  1. 0-10Introduce bias versus measurement error: definitions and examples in physiology studies
  2. 10-30List possible bias and error sources specific to your own study
  3. 30-50Choose a graph type: bar, line, scatter, or box plot -- justify the choice for your comparison
  4. 50-65Draft the graph with labeled axes, units, and a title
  5. 65-77Add a bias-and-error annotation note on the graph and submit
  6. 77-80Exit check: which bias source is most likely to affect your conclusion and why?
Mr. Mendoza's 5-minute intro
  • Before you run your statistics, you need to know what could have gone wrong with your data.
  • Today you will name the bias and measurement-error sources in your study and choose the graph that best shows your comparison.
  • A graph that hides important variation is a misleading graph -- you will learn to make graphs that reveal what the data actually says.
  • Graph literacy and error analysis appear in the data-analysis skills tested by WebXam 072125.
Know by the end
  • The specific bias and measurement-error sources that threaten validity in a physiology study.
  • How to select the appropriate graph type for a comparison between two conditions.
  • How acknowledged bias or error must appear in any honest data interpretation.
Open this PLTW section today

Bias, error, graph choice, CER conclusion, limitations. · Bias, error, graph choice

Day 2 of this lesson. Open this exact section in myPLTW (find it in Clever, Microsoft sign-in), then do the work below.

Do this: Open Problem 2 in your myPLTW course shell and locate the graphing or data-visualization activity to review the graph format requirements.

Complete

Mark the graphing activity complete in your tracker after submitting your graph draft.

How far to get

The biometric-privacy CER is done; by end of today your draft graph with labeled axes and a bias-and-error note should be submitted.

Upload as evidence

Draft graph with labeled axes, units, and a bias-and-error annotation note turned in on the class site or in person.

The official PLTW activity stays inside myPLTW. If myPLTW will not open, use F1 and E1-E3 on this page to complete today's local evidence decision, then make up the official activity when access returns. Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.

Today's PLTW tracker · fill in and submit

Check things off as you work, then submit. This tells Mr. Mendoza how you're doing so he can help the class. It does not replace turning in your producible through the submission route shown below.

Use the code Mr. Mendoza gave you, not your name. Saved on this device.

Bias, error, graph choice, CER conclusion, limitations.Day 2 of this projectSee the full week plan
Today's PLTW target

Bias, error, graph choice, CER conclusion, limitations. · Bias, error, graph choice

Open Problem 2 in your myPLTW course shell and locate the graphing or data-visualization activity to review the graph format requirements.

The biometric-privacy CER is done; by end of today your draft graph with labeled axes and a bias-and-error note should be submitted.

This is how Mr. Mendoza sees the class keeping pace with PLTW. Be honest, it only helps if it is accurate.

1 · What you do today

🎯 Identify sources of bias and error and choose the right graph for your physiology data.

  • List possible sources of bias and measurement error in your study.
  • Decide which graph type best shows your comparison.
  • Draft the graph with labeled axes and units.
  • Note how bias or error could affect what the graph shows.
  • Submit your graph draft with a bias-and-error note.
2 · What you turn in

Data table: Draft graph showing the physiology comparison with labeled axes, units, a title, and an annotated bias-and-error note.

Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not. Use the checklist just below and upload by 11:29 PM for full credit. Absent with an excused absence? You get two school days for every day you were absent, so this deadline moves with you.

3 · Who's doing what (team)
TaskWho
List possible sources of bias and measurement error in your study._______
Decide which graph type best shows your comparison._______
Draft the graph with labeled axes and units._______
Note how bias or error could affect what the graph shows._______
Submit your graph draft with a bias-and-error note._______

Working solo? Put your own name in "Who" for every row.

4 · Words I can use correctly
5 · I'm successful today when I can…
  • You can name specific bias and error sources in your study.
  • You can justify your graph choice for the comparison.
6 · Reflection & next steps
Where are you today?0/7 checked
Pick your period and code first.
Your 4 steps today
  1. 1
    Do this
    Identify sources of bias and error and choose the right graph for your physiology data.
  2. 2
  3. 3
    Submit this
    Data table: Draft graph showing the physiology comparison with labeled axes, units, a title, and an annotated bias-and-error note.
  4. 4
    Submit it here
    1. 1Open the drop folder.
    2. 2Sign in with your district Microsoft account, not a personal one.
    3. 3Upload the file, named Lastname_Firstname__Assignment Title.
    4. 4Your own upload panel says Uploaded with a green check: that is your receipt.
    Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not. Biotechnology for Health (Biomedical Innovations) › Bias, error, graph choice, CER conclusion, limitations. › Data table
    Open the drop folder
Were you absent? Jump to the make-up plan
Learn it · deck, reading, and vocabulary
Socratic teaching slide deck

The deck carries the prior idea forward, lets you inspect an analogy, maps the rule to biology, and ends with the same evidence decision and exit ticket used on this page.

Generated from this lesson's canonical data with a red-team citation check.

Carry forward

A privacy safeguard has to be designed into a study before data collection, because it decides what you are allowed to measure and share, so a physiology analysis built without one cannot be trusted or reused.

Daily take-home

The graph type encodes a claim about your data, so choosing one that fits a two-condition comparison (and starting the axis fairly) is what lets the real pattern show instead of a manufactured one.

Inspect the analogy

A detective board holds observations, possible explanations, and one next question.

  1. Which notes are direct observations?
  2. Which notes are explanations?
  3. What new evidence would separate the explanations?
Rule

Keep observations separate from explanations, then collect the evidence that can distinguish the options.

Where it breaks

Biomedical investigations use controlled procedures and validated measurements, not intuition alone.

Map the analogy to biology
  • Board notes map to E1-E3.
  • Possible explanations map to the decision options.
  • The next question maps to the evidence-based action.
Read this first

Driving question: You measured two conditions (say resting versus post-exercise heart rate). Which graph makes the real difference between them visible, and what bias in how you collected the data could be faking that difference?

What you already know: A privacy safeguard has to be designed into a study before data collection, because it decides what you are allowed to measure and share, so a physiology analysis built without one cannot be trusted or reused.

New idea: The graph type encodes a claim about your data, so choosing one that fits a two-condition comparison (and starting the axis fairly) is what lets the real pattern show instead of a manufactured one.

Visual or model: F1. F1. A lesson illustration or teaching diagram for Bias, error, graph choice. Use it with E1-E3; it is a model or context image, not experimental or patient data. What to notice: Trace the labeled system, test, or design relationship and identify which evidence should trigger revision.

  1. Observe or measure the relevant feature in Bias, error, graph choice.
  2. Organize the observation with a stable evidence ID.
  3. Apply this rule: Keep observations separate from explanations, then collect the evidence that can distinguish the options.
  4. Choose the option the evidence supports and state the limit of the conclusion.

Real biomedical example: You measured two conditions (say resting versus post-exercise heart rate). Which graph makes the real difference between them visible, and what bias in how you collected the data could be faking that difference?

What the evidence supports: E1-E3 and F1 support the daily take-home when the response meets the stated success criteria.

What it cannot prove: The package does not support claims beyond this lesson's or any real patient diagnosis.

Vocabulary:
  • bias: A systematic error in how data is collected or interpreted that tilts results in one direction, making conclusions less accurate or unfair.
  • limitation: A weakness or boundary of a study, design, or method that restricts how far its results can be trusted or applied.
  • replication: Repeating a study to see if the result holds; a key test of whether a finding is real.
  • : A result unlikely to be due to chance, often shown by a p-value below a set threshold such as 0.05.
  • evidence: The facts, data, and cases that carry your claim. Opinions are free; evidence costs homework.

Use it now: Choose one decision option. Cite E1 and E3, then explain how the rule connects the evidence to your choice.

Go further, optional: The source links below are optional enrichment. Every fact required for today's local evidence decision appears in this lesson package.

Evidence set and decision
E1 · Observation

The specific bias and measurement-error sources that threaten validity in a physiology study.

Limit: E1 supplies context or an observation; it does not by itself establish the explanation.

E2 · Mechanism

The graph type encodes a claim about your data, so choosing one that fits a two-condition comparison (and starting the axis fairly) is what lets the real pattern show instead of a manufactured one.

Limit: E2 is a teaching statement or comparison and must be checked against the task evidence.

E3 · Result

You can name specific bias and error sources in your study.

Limit: E3 supports only the result or product criterion named here; it cannot justify a broader clinical or causal claim.

PLTW-BFH-2027-03-11 · Simulated classroom evidence scenario

Your role: biomedical design team member

Decision: Your team must decide what the evidence from Bias, error, graph choice supports before submitting the labeled and result claim named on the lesson page.

  • Select the option best supported by E1-E3.
  • Select a reasonable alternative and name the evidence it would require.
  • Delay the claim because the evidence does not distinguish the options.

Response: State one choice, cite at least two evidence IDs, explain the rule that connects them, and add one limitation. Submit it as the labeled and result claim.

Claim ceiling: The supplied lesson evidence can support an observation, pattern, classroom mechanism, or next-step decision about Bias, error, graph choice. It cannot by itself prove causation, establish a real clinical diagnosis, or justify action outside this classroom task.

Math moment
Formula or setup

= final volume / sample volume. New concentration = starting concentration / dilution factor.

Worked parallel example

Mix 1 mL of sample to a final volume of 10 mL. The is 10. A 100 mg/mL starting sample becomes 10 mg/mL.

Units and reasonableness

Use the same volume units before dividing. Concentration keeps its original concentration unit.

Try it with today's data

Apply the same setup to one supplied dilution or dose. Show the factor, new value, units, and a reasonableness check.

Watch the trap

Students often think Students think picking a graph is decoration, so they choose whichever one looks nicest or whichever the spreadsheet suggests first.. The trap: The graph type is not a style choice. A line graph implies change over a continuous variable like time, and using it for two separate categories invents a trend that is not there, so the wrong graph can manufacture a pattern your data never contained.

Worked example · a parallel case (guides, does not reveal)
Draft comparison graph with a bias-and-error note
Completes: Completes the Problem 2 graph-choice step: a drafted graph of the two-condition physiology comparison with labeled axes and an annotated note on bias and measurement error.

Comparison: mean heart rate at rest vs after light activity.

Graph choice: a bar graph, because I am comparing the mean of two categories (rest, activity), not a trend over continuous time. Bars make the two means easy to compare side by side.

Axes: x-axis = Condition (Rest, After activity); y-axis = Mean heart rate (bpm), starting at 0 so the bars are not visually exaggerated. Title: 'Mean Heart Rate by Activity Condition'. I added error bars showing the standard deviation.

Bias-and-error note:

  • Possible bias: I tested only one subject, so the result may not represent other people (selection bias).
  • Possible measurement error: sensor placement could shift between trials, adding noise. I reduced this by keeping the sensor in the same spot.
  • How it shows in the graph: the SD error bars make the measurement spread visible, so a reader can see the difference is larger than the within-group variation.
Bar graph comparing mean heart rate at rest (72 bpm) and after activity (97.6 bpm), with the activity bar taller.
Why this matters

This model shows the level of evidence and organization needed to complete: Completes the Problem 2 graph-choice step: a drafted graph of the two-condition physiology comparison with labeled axes and an annotated note on bias and measurement error.

Build yours step by step
  1. Name the variables and include units.
  2. Enter observations without changing the raw values.
  3. Check labels, calculations, and patterns before interpreting the data.
Change it for a new task

Keep the structure. Replace the question, facts, measurements, and evidence. Then recheck units, vocabulary, and whether the conclusion goes beyond the evidence.

Also due today: Submit your graph draft with bias-and-error note on the class site, or hand it to Mr. Mendoza in class by end of period.

See the full worked example
Portal terms
CER:
Claim, Evidence, Reasoning: make a claim, back it with evidence, explain your reasoning.
SOP:
Standard Operating Procedure, the exact steps to follow (especially in a lab).
Tracker:
Your PLTW progress log where you record completed evidence.
myPLTW:
The PLTW course site where you do the online activities. Find it in Clever with your Microsoft sign-in, right next to Schoology.
This unit's vocabulary

Tap the speaker to hear a term. Add two of these to your notebook glossary with a definition and an example in your own words.

Build your vocabulary · optional, for extra credit

Pick just 2 or 3 words from today and make them yours: write what each one means in your own words, name the context clue or evidence that helped, then give one example from what you actually did in Bias, error, graph choice. Try your own words first; the glossary is there if you get stuck. This is voluntary and counts as extra credit, so keep it short.

bias
limitation
replication
statistical significance
evidence

Saved on this device. Show Mr. Mendoza or add these to your notebook glossary to claim the extra credit.

Teacher-posted resources

Classroom documents for this lesson are posted in Schoology. Open Clever, then Schoology, and find each one by the name shown on its card.

Catch-up / reteachFor: Need extra support
PLTW BI Activity 2.1.3 Making Results Meaningful
worksheet/handoutPosted in Schoology
Open in Schoology

Use this if you were absent, got stuck, or need another pass before you submit the lesson artifact.

Placement rationale

Matched Statistical analysis and t-test reasoning by path:Biomedical-Innovations/Problem-2_Human-Physiology/2.1_Human-Physiology; keywords:statistical analysis. Score 138. Visibility: student-schoology (student-facing resource; link through Schoology rather than local path).

Catch-up / reteachFor: Need extra support
PLTW BI 2.1.3 Statistical Analysis Three Examples Resource
worksheet/handoutPosted in Schoology
Open in Schoology

Use this if you were absent, got stuck, or need another pass before you submit the lesson artifact.

Placement rationale

Matched Statistical analysis and t-test reasoning by path:Biomedical-Innovations/Problem-2_Human-Physiology/2.1_Human-Physiology; keywords:statistical analysis. Score 134. Visibility: student-schoology (student-facing resource; link through Schoology rather than local path).

Use during lessonFor: Everyone
BI Project 2.1.1 Scientific Research Student Activity
worksheet/handoutPosted in Schoology
Open in Schoology

Open this when the class reaches this activity and use it to complete the required lesson artifact.

Placement rationale

Matched Statistical analysis and t-test reasoning by path:Biomedical-Innovations/Problem-2_Human-Physiology/2.1_Human-Physiology. Score 126. Visibility: student-schoology (student-facing resource; link through Schoology rather than local path).

How to get there: open Clever and sign in with your Microsoft (district) account. Both myPLTW and Schoology are in Clever. Do the activity in myPLTW. Turn the work in on this site or hand it to Mr. Mendoza, because that is the step that counts as submitted. Schoology only shows your report-card grade later.

Check yourself · commit, then reveal

Claim ceiling for this check: The supplied lesson evidence can support an observation, pattern, classroom mechanism, or next-step decision about Bias, error, graph choice. It cannot by itself prove causation, establish a real clinical diagnosis, or justify action outside this classroom task.

Quick self-check · commit, then reveal

You are comparing average heart rate in two conditions, rest and after exercise. Is a bar graph or a line graph the honest choice, and where should the value axis start?

How sure are you?

Write an answer and pick a confidence to unlock the key.

Cumulative WebXam review · flash practice

Fast retrieval with instant answers, not the commit-then-reveal check above. Try each from memory first: write what you remember about the earlier units, then check yourself here.

Tap an answer to check it · nothing is recorded or graded
[Review: Prototyping the ER: floor plans, process flow, and human factors] How should you properly prepare hydrochloric acid (HCl) for disposal?
[Review: Pitch and revise: evidence-based feedback and intro to study design] Experimental results fall significantly outside the expected range. What should you do first?
[Review: Reading the body's data: study types, sample size, and the t-test] What is the purpose of an experiment measuring blood glucose after giving a drug or a placebo?
Where should you locate information on the maintenance history of a glucometer?
Go further and get help
Lab · prepare, conduct, complete
1Prepare
Pre-lab pass · clear all six to go to the bench
0/6

I can name the procedure's purpose and the evidence I will record. I can identify each named hazard and the control that reduces it: Wear the required PPE, keep the bench clear, handle equipment only as directed, and know where the eyewash, sink, and spill kit are before you start. My data table is ready before materials are handled.

Finish the checklist before you handle any material.

Bring / set up
Lab computers with spreadsheet softwareSaved physiology dataset from prior weekGraphing or charting toolCER conclusion templateCalculatorProjector for sharing graphs
Safety · specific to today's hazards
  • Wear the required PPE, keep the bench clear, handle equipment only as directed, and know where the eyewash, sink, and spill kit are before you start.
  • Human samples and data stay private: label with a code, never a name, and dispose of materials in the correct waste container, then wash your hands.
Review Lab Safety (rules, PPE, SDS, emergencies) and check your contract + test
2Conduct (Argument-Driven Inquiry)
  1. 1Before materials are handled, identify the purpose, variables or comparison, controls, measurement units, and stop-work condition.
  2. 2List possible sources of bias and measurement error in your study.
  3. 3Decide which graph type best shows your comparison.
  4. 4Draft the graph with labeled axes and units.
  5. 5Note how bias or error could affect what the graph shows.
  6. 6Submit your graph draft with a bias-and-error note.
  7. 7Record each result in the prepared table before interpreting it. Mark missing, repeated, or invalid results truthfully.
  8. 8Complete the named cleanup and waste route, remove PPE safely, wash hands when required, and confirm the station is ready for the next group.
Prepare this data table before materials are handled
Trial or sample IDIndependent conditionMeasured result with unitsObservation before interpretationQuality-control note
     
     
     
Khan Academy Statistics and Probability
3Complete
Argue from your evidence, then compare what you predicted to what happened. Error analysis names a specific method limit, never "human error".
You predicted

Before the procedure, predict the result and cite the rule behind the prediction.

What actually happened

After the procedure, compare the result with the prediction and name one limitation or source of uncertainty.

Your lab report is graded on the rubric below, with extra weight on error analysis and method.
Where this leads: careers
What to do if you were absent
If YOU are absent

Today is individual work you can do from home: complete the same target above, then submit your Data table.

Open the drop folder

Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.

If MR. MENDOZA is absent

Class still runs. Complete the online activity above (it's self-guided). Need the concept taught without a teacher? Use this authoritative explainer:

Khan Academy Statistics and Probability
How this is graded
For: Data table: Draft graph showing the physiology comparison with labeled axes, units, a title, and an annotated bias-and-error note.
  • Complete
    Every required part of the artifact is present, nothing left blank.
  • Accurate
    The science and the data are correct and match the evidence.
  • Scientific reasoning
    You explain your claim with evidence and reasoning (CER), not just an answer.
  • Professional communication
    Clear, organized, labeled, and written the way a clinician or scientist would.
  • Submitted
    Turned in the right way, on the class site or handed to Mr. Mendoza in class, and confirmed. Not in Schoology: that is where the report-card grade appears later.
  • Error analysis and method · counts double
    Name a specific limit of the method and how it moved your result, and compare what you predicted to what happened. "Human error" does not count; say what about the procedure or instrument caused it.