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SCIENCE
Science: GeneralWhat is science?• Science is a process used to discover
more about the natural world• Doing science means answering
questions or coming up with explanations about the natural world.
• The answer itself is not the science, the science is the process
Science: GeneralWhat is science?
Science is NOT about HOW MANY answers you know…but how you BEHAVE when you don’t know.
What caused this?
Do these fit together?
How did this rock form?
How do you explain this?
• Snap freezing video clip
Why do dirt roads become washboarded?
Normal people Wonder
Scientist’s Investigate
ASTROLOGY • Astronomical
events governed their destiny.
• There is NO PROOF of this.
• Religion
What is Astrology?
Fact?• Fact: Something known to be true?• Very few things we speak or write about
really possess this special status. • Factual status may be assigned to some events, carefully.
– Events confirmed by a multitude of witnesses, demonstrated repeated in the laboratory, checked and rechecked--by both formal investigation and everyday experience: these may be considered fact.
– Example, it snowed last night• But most other statements, are not
likely to be statements of fact. (especially regarding people, groups of people, or human nature in general)
Fact• Scientific Fact:
– an observation that has been confirmed repeatedly and is accepted and agreed upon as being true (by competent people)
• It must be based on unmistakable evidence that has been repeatedly confirmed
• You can disprove something though– the absence of disproof is considered support– If nobody has proved it wrong it’s easier to
accept
• Fact vs. Belief WS – if time or as a group/class discussion
Science
• Science – – answering questions or coming up with
explanations
Science is NOT about HOW MANY answers you know…but how you BEHAVE when you don’t know.
Learning Target
Review from last unit…• I know the reasons scientists conduct
investigations: (9.1.1.1.2) – to explain observed phenomena– to discover new aspects of the natural world– to test conclusions of prior investigations
• to possibly identify faulty reasoning (9.1.1.2.2)• to possibly point out statements that are not based on
scientific evidence (9.1.1.2.2)• to possibly propose alternative explanations (9.1.1.2.2)
– to test predictions of current theories
Scientific Inquiry
• Science – Generally starts with…• Observations –
Be aware of (or avoid) Inferences DON’T JUMP TO CONCLUSIONS – There may be more than one possible explanation
Lead to…• Hypothesis – Allows us to make …• Prediction –
Scientific Inquiry
• Prediction – – If the prediction proves to be correct
over and over again– Leads to a proper
• Explanation– Answer to the original question
• Gets us closer to the Truth
Learning Target
CS1:• I know the characteristics of science:
(9.1.1.1)– Empirical Criteria– Logical Argument– Skeptical Review
Science CharacteristicsThese 3 things separate science from non-science.In order to convince scientists of “facts”, we need to provide them with...
1. Empirical Criteria = evidence2. Logical Argument = makes sense3. Skeptical Review = others need to agree
Science Characteristics1. Empirical Criteria• In science, we need EVIDENCE.
– Evidence leads us to an explanation• Empiricism - Method of observation and
experiment used in science. – Based on the idea that the origin of all
knowledge comes from our senses. • Much like a detective trying to solve a crime
Learning Target
CS2:• I can explain what it means to make a
logical argument (9.1.1.2.3).
Science Characteristics2. Logical ArgumentWhat is a logical argument?Let’s break it down into components…• An argument is an attempt to demonstrate
the truth of a statement– The definition doesn’t say anything about
whether you succeed… it is just an attempt
Logical Argument• There are good arguments (valid) and bad
arguments (invalid) – very subjective terms
• Subjective - influenced by personal feelings, tastes, or opinions
• Objective – NOT influenced by…
Logical ArgumentWho wins?
vs.
What is a logical argument?• A valid (good) argument is one that is
capable of convincing someone about the truth of the statement.– It doesn’t have to convince you, it just has to be
able to convince someone who is competent– You don’t have to agree with a statement for it
to be a valid argument
Logical Argument
2nd term…• Logic: a system of reasoning
Logical Argument
Put the definitions for Logic and Argument together and you get…
• Logical Argument: a system of reasoning that is capable of convincing someone (who is competent) that a statement is true.
• An argument that makes sense to someone who is competent – again, you don’t have to agree with it
Logical Argument
• To make a logical argument, you draw conclusions from evidence or principles. In order to accept your argument as logical, your audience must find your evidence valid and convincing.
• Much like the detective trying to solve the crime, they need evidence and then have to show how the evidence proves the defendant is guilty
Logical Argument
Learning Target
CS3:• I can identify (and evaluate) points of
reasoning in a claim. (9.1.1.2.3)
Ex.Premise: If you oversleep, you'll be late.Premise: You aren't late.Conclusion: So ???
A. You did oversleep.B. You're late.C. You didn’t oversleep.D. None of the above – the
argument is not valid (no good) If the one of the premises (evidence) is
invalid, the conclusion is also invalid.
Logical Argument
Is the first premise always true?
What is NOT logical?• Monty Python worst logic - Witch Hunt
http://www.youtube.com/watch?v=I8ZWgrf6Qds&NR=1
Logical Argument
Witches Burn because…Witches are made of woodWood BurnsWood FloatsDucks FloatIf someone weighs the same as a duck, they are a witch
Fact?FactFactFactFallacy
Logical Argument
Even if all of the premises (pieces of evidence) are true, the conclusion can still be invalid.
• Logic: How to Argue Without Cheating WS• Logic Puzzles
Logical Argument
Learning Target
CS4• I know that a scientific conclusion must be
validated by the scientific community through various methods (9.1.1.1.3).
Science Characteristics3. Skeptical ReviewSkepticism is any questioning attitude, or
some degree of doubt regarding claims that others might have taken for granted.
In science it is good to have a “healthy” amount of skepticism - question everything
…but not up to the point where you never believe anything.
Skeptical ReviewThe Fine Art of
Baloney Detection by Carl Sagan
from The Demon-Haunted World
There’s a sucker
born every
minute… don’t
let it be you
Skeptical ReviewThe Fine Art of Baloney Detection:• “What skeptical thinking boils down to is the
means to construct, and to understand, a reasoned argument” AND be able “to recognize a fallacious or fraudulent argument.”
• “The question is not whether we like the conclusion that emerges out of a train of reasoning, but whether the conclusion follows from the premise or starting point and whether that premise is true.”
Skeptical ReviewThe Fine Art of Baloney Detection:Carl Sagan says…
“In the course of their training, scientists are equipped with a baloney detection kit. The kit is brought out as a matter of course whenever new ideas are offered for consideration. If the new idea survives examination by the tools in our kit, we grant it warm, although tentative, acceptance”
Skeptical Review• Baloney in Movies, TV and Ads WS
• Start with a list of the12 things that Carl says should be done in science. (What are the tools in the tool kit we should use?)
Skeptical ReviewThe Fine Art of Baloney DetectionAmong the tools:• Wherever possible there must be
independent confirmation of the "facts."• Look at all points of view
– Encourage substantive debate on the evidence by knowledgeable proponents of all points of view.
Don’t believeeverything youthink….
It is the mark of an educated mind to be able to entertain a thought without accepting it.Aristotle
The Fine Art of Baloney DetectionAmong the tools:
• Arguments from authority carry little weight – "authorities" have made mistakes in the past.– even “experts” have been wrong in the past
so wise in the ways of science
The Fine Art of Baloney DetectionAmong the tools:
• Every premise in an argument must be accurate -- not just most of them.
• The whole of the argument must also reach a logical conclusion.
• Atoms are colorless
• Cats are made of atoms
• Cats are colorless
The Fine Art of Baloney DetectionAmong the tools:
• Spin more than one hypothesis. – think of all the different ways in which it could be
explained.
• Try not to get overly attached to a hypothesis just because it's yours.
• Always ask can the hypothesis be proven wrong, at least in principle. – Propositions that are untestable, unfalsifiable
are not worth much. – You must be able to
check claims out.
The Fine Art of Baloney DetectionAmong the tools:
• The reliance on carefully designed and controlled experiments is key
The Fine Art of Baloney DetectionAmong the tools:
– We will not learn much from just thinking about it.
– What happens if we can invent several explanations? How do we decide among them?
– We don't. We let the experiment do it.
• Occam's Razor. This convenient rule-of-thumb urges us when faced with two conclusions that explain the data equally well to choose the simpler.
The Fine Art of Baloney DetectionAmong the tools:
• Variables must be separated. – Suppose you're seasick, and given both an
acupressure bracelet and 50 milligrams of meclizine. You find the unpleasantness vanishes. What did it -- the bracelet or the pill? You can tell only if you take the one without the other.
The Fine Art of Baloney DetectionAmong the tools:
• Quantify. – With numerical quantity you are better able to
discriminate among competing hypotheses. – What is vague and qualitative is open to many
explanations.
The Fine Art of Baloney DetectionAmong the tools:
• Often the experiment must be done "double-blind," – so that those hoping for a certain finding are not
in the potentially compromising position of evaluating the results.
– In testing a new medicine, for example, you might want the physicians who determine which patients' symptoms are relieved not to know which patients have been given the new drug. The knowledge might influence them even if only unconsciously.
The Fine Art of Baloney DetectionAmong the tools:
Going back to…• Always ask can the hypothesis be proven
wrong, at least in principle. – Skeptics must be given the chance to follow
your reasoning, to duplicate your experiments and see if they get the same result.(This is why procedures are so important)
– the absence of disproof is considered support– Support leads to FACTUAL status
The Fine Art of Baloney DetectionAmong the tools:
Learning Target
CS5:• I know the reasons scientists conduct
investigations: (9.1.1.1.2) – to discover new aspects of the natural world– to explain observed phenomena– to test conclusions of prior investigations
• to possibly identify faulty reasoning (9.1.1.2.2)• to possibly point out statements that are not based on
scientific evidence (9.1.1.2.2)• to possibly propose alternative explanations (9.1.1.2.2)
– to test predictions of current theories
Scientific Investigations
• Reasons scientists conduct investigations:CuriosityPeer Review:– to test conclusions of prior investigations
• Is their logic wrong?• Is their scientific evidence acceptable?• Is there another possible explanation?
Scientific Investigations
• Reasons scientists conduct investigations:CuriosityPeer Review:– to test predictions of current theories
• If what others have found in the past is true, then ______________ should also be true.
• Ex. If the Earth is making new crust and it’s diameter is not getting bigger, then it is being destroyed somewhere else.
Scientific Investigations
• Reasons scientists conduct investigations:CuriosityPeer Review:– to test conclusions of prior investigations– to test predictions of current theories– some variation of the above– some combination of the above
Science Characteristics3. Skeptical ReviewSkeptical Review in science is the way…• Scientists examine the work/claims of
others with a skeptical eye and question their results.
• Competent people reach close agreement on what we will accept as factual.
• Is there credible supporting evidence?• Is the claim supported by a logical argument?
The scientific community engages in certain quality control measures to eliminate bias. 3 Main ways Scientific Conclusion are validated by the scientific community:
• Independent duplication = Two or more scientists from different institutions investigate the same question separately and get similar results.
• Scientific Journal (Peer-reviewed)= A journal that publishes articles only after they have been checked for quality by several expert, objective scientists from different institutions.
• Presentation/Lecture = scientists present their findings to colleagues
The absence of disproof is considered support
Peer Review
Saturn's rings: Leftovers from a cosmic murder?
“And those spectacular and colorful rings are the only evidence left. As the doomed moon made its death spiral, Saturn robbed its outer layer of ice, which then formed rings, according to a new theory published online Sunday in the journal Nature.”
By SETH BORENSTEIN, AP Science Writer Seth Borenstein, Ap Science Writer – Sun Dec 12, 2010 1:05 pm ET
Peer Review
Strange Particles May Travel Faster than Light, Breaking Laws of Physics
By Clara Moskowitz | LiveScience.com – 9/22/2011
Physicists have found that tiny particles called neutrinos are making a 454-mile (730-kilometer) underground trip faster than they should — more quickly, in fact, than light could do. If the results are confirmed, they could throw much of modern physics into upheaval. “That's why such a claim should be treated very carefully and validated as many ways as you can.”
Peer Review
Strange Particles May Travel Faster than Light, Breaking Laws of Physics
By Clara Moskowitz | LiveScience.com – 9/22/2011
Inviting skepticismRealizing full well how scandalous the results will be if they are borne out, the scientists behind OPERA, led by Antonio Ereditato of the University of Bern, have decided to make their data public, in hopes of inviting scrutiny that could make sense of such radical findings. The scientists also intend to gather more data and further analyze their measurements in order to establish them more fully, or refute them. Their results will be published Friday (Sept. 23) on the physics preprint site ArXiv.
Peer Review
Strange Particles May Travel Faster than Light, Breaking Laws of Physics
By Clara Moskowitz | LiveScience.com – 9/22/2011
Inviting skepticism…One of the best hopes to verify or disprove the findings comes from Fermilab's MINOS experiment, which also sends neutrinos flying underground over a similar distance to end up at the Soudan mine in Minnesota. “One of our next objectives is going to be trying to verify or disprove this result as hard as we can.”
CERN plans to discuss the findings Friday during a public seminar that will be broadcast at http://webcast.cern.ch
What is Science?
Are the following True or False?1.Science is concerned with understanding how nature
and the physical world work.2.Science can prove anything, solve any problem, or
answer any question.3.Any study done carefully and based on observation is
scientific. 4.Science can be done poorly. 5.Anything done scientifically can be relied upon to be
accurate and reliable.6.Different scientists may get different solutions to the
same problem.7.Knowledge of what science is, what it can and cannot
do, and how it works, is important for all people.
1. Science is concerned with understanding how nature and the physical world work.
Science is a process by which we try to understand how the natural and physical world
works and how it came to be that way.
• Science actually attempts to disprove ideas (hypotheses).
• Science is limited strictly to solving problems about the physical and natural world.
• Explanations based on supernatural forces, values or ethics can never be disproved and thus do not fall under the realm of science.
2. Science can prove anything, solve any problem or answer any question.
3. Any study done carefully and based on observation is scientific.
• Science must follow certain rules.• Need for evidence• Logical Argument• Skeptical Review
• The rules of science make the scientific process as unprejudiced as is possible… more on this coming up
4. Science can be done poorly.
• Science can be done poorly, just like any other human endeavor.
• Quality control mechanisms in science increase the reliability of its product.
5. Anything done scientifically can be relied upon to be accurate and reliable.
6. Different scientists may get different solutions to the same problem.
• Results can be influenced by the race, gender, nationality, religion, politics or economic interests of the scientist.
• Sampling or measurement bias can result in different solutions to the same problem… more on this coming up
People need to be able to evaluate scientific information in order to make informed decisions
about:
• Health care• Environmental issues• Technological advances• Public health issues
7. Knowledge of what science is, what it can and cannot do, and how it works, is important for all
people.
• Objectivity is the key to good science.• Objective = Not influenced by feelings,
interests and prejudices; • Subjective = Influenced by feelings,
interests and prejudices; • To be objective, experiments need to be
designed and conducted in a way that does not introduce bias into the study.
How do you do “good” science?
Learning Target
CS6• I can define bias (9.1.1.1.5)
BiasBias = preference for one thing over another
&/or a systematic error that causes a misleading presentation of material
Biased = SubjectiveUnbiased = Objective
In Science, it is more than just having a prejudice… it has to affect the way you present your claim or the validity of your evidence
• may be Intentional• most often in science, Unintentional
Learning Target
CS7• I can identify a variety of sources of bias
(9.1.1.1.5)– Gender bias, misconception, cultural bias,
funding bias, procedural bias, individual bias or prior experience, political bias
Bias
Types of Bias:Human BiasExperimental Bias (a.k.a. mathematical bias)
Human Bias… the personal biases that the tester/experimenter has.
Bias
Human sources/types of bias:– gender bias– cultural bias– political bias– funding bias– individual bias based
on prior experience– misconception
Human Bias Example:• I want to know what the favorite color is of students
here at Coon Rapids is.• My favorite color is red.• So I put on my favorite shirt (red) and stop students in
the hallway and ask them what their favorite color is.• Since I like red, I might more often end up asking
students who are wearing red to take part in my survey• My results are then probably going to show more
people picking red than any other color.• Because My favorite color is red… I am biased towards
red and it will probably show up in my results • And… make my results misleading
Bias
Types of Bias:Human BiasExperimental Bias (mathematical bias) –
something is wrong in the experiment that leads to a consistent error in estimating a value.
Different Categories of Experimental Bias
• RESEARCH BIAS– Quantitative Research Bias– Qualitative Research Bias
• DESIGN BIAS• SELECTION/SAMPLING
BIAS– Omission Bias– Inclusive Bias– Sample Bias– Loss-to–Follow-up Bias– Spectrum Bias– Referral Bias– Participation Bias– Self-Selection Bias
• PROCEDURAL BIAS• MEASUREMENT BIAS• INFORMATION/
OBSERVATION BIAS– Interviewer Bias– Confounding– Response Bias– Reporting Bias– Publication Bias
Experimental Bias
• Experimental Bias can result anytime during the experimental process: – Poor inferences, bad interpretations to start
with– Flaws in the way the study/exp. was designed– Consistent errors in measurement – Poor conclusions reached due to flawed data
or data collection
Experimental Bias
Two Main types of Experimental Bias that result in inaccurate evidence
• Sampling Bias• Measurement Bias
Experimental BiasSampling Bias• Sample = A group of units selected to be
“measured” from a larger group (the population).
• Sampling bias is when the sample used is not representative of the population or inappropriate for the question asked.
Sample Bias
Factors that contribute to sampling bias:• SELECTION OF SAMPLE: Does the
composition of the sample reflect the composition of the population
Factors such as location, age, gender, ethnicity, nationality and living environment can affect the data gathered.
Sample Bias
Factors that contribute to sampling bias:• SAMPLE SIZE: Is the sample big enough to
get a good average value?
• Opening day 2013, Joe Mauer goes 3 for 4 giving him a batting average of .750 so… he’ll probably hit .750 for the season?
Experimental Bias
Measurement Bias: There is a problem in the method used to collect the data which results in the data not matching reality.
Is there something: – Wrong with the experimental set-up– Missing from the experiment– Added to the experiment
Would you be
honest in a
survey on
shoplifting if
there was a
cop in the
room?
Learning Target
CS9• I can suggest ways to limit bias in
scientific research (9.1.1.1.5)
Sample Bias
Minimize Sample Selection Bias:• Use a RANDOM SAMPLE = every
individual has an equal likelihood of being chosen.
• Think: Pick an appropriate group to draw your sample from.
Measurement Bias
Minimize Measurement Bias…• Think: Ensure that measurements are
taken accurately• Think: No additions to the environment
that will influence results
Measurement Bias
Minimize Measurement Bias…• Think: Is the experiment designed to minimize
the effect of multiple variables.
• Are multiple factors properly accounted for to justify the interpretation of the data?
Ex. Design a study to determine the link between sleep and test results.
Bias Summary
• Good Science depends on a well-designed experiment that minimizes bias.
• Think about the question being asked… then pick the appropriate:– Sample (group)– Sample Size– Measurement Technique
Learning Target
CS8• I can examine the influence of bias in
scientific research (9.1.1.1.5)
• Understanding Bias & Teen Smoking (USGS) WS
Examining the Data SourceInvestigations of Passive Smoking Harm: Relationship between Article Conclusions & Author Affiliations• This is real research and clearly shows that bias
unfortunately can and does affect scientific research Number (%) of Reviews
Article Conclusion Tobacco Affiliated Authors (n=31)
Non-Tobacco Affiliated Authors (n=75)
Passive smoking harmful 2 (6%) 65 (87%)
Passive smoking not harmful 29 (94%) 10 (13%)
Significance Χ2=60.69; P<.001
Barnes, Deborah E. 1998. Why review articles on the health effects of passive smoking reach different conclusions. JAMA. 279(19): 1566-1570.
Bias Summary
Think about Bias…• When you are designing/performing an
experiment or study• Looking at the results/conclusions of
others
Are you going to accept the results as Fact?
Look for signs of bias!
• Language used• Appropriate data reported to
back conclusions• Data source
Identifying Bias
Language to Watch For“Scientifically-proven” * Science does not seek to prove but to disprove * Be suspicious of this claim!
* Words should be chosen very carefully to avoid exaggeration or claims not supported by data.
Look for Data
Is There Sufficient Data? * Scientific conclusions should only report what the data
supports.
THE DATA
SHOULD
CONVINCE YOU,
NOT THE WORDS
USED!Emotional appeal * Conclusions should be
data-based * Emotional appeals usually
are not data-basedGlobal
Warming
Consider the Data Source• All organizations probably attempt to
produce unbiased data.• However, it is important to understand the
organization’s motivation to be able to identify potential bias.
• In some situations, the need to promote special interests or make profits may lead to bias.
Consider the Data Source
What are the motives of the Source?1. Corporate Research2. Special Interest Groups 3. University Research4. Government ResearchRemember: It’s only biased if the results end up being misleading. Motivation for doing research does not automatically result in bias.
Actually Check the Source
“Asparagus Cures Cancer”• http://www.snopes.com/medical/disease/asparagus.asp
• 'Asparagus for cancer' printed in Cancer News Journal, December 1979
• “..unable to locate a copy of that article or find information about …the article's purported authority, Richard R. Vensal, D.D.S.” (usually = Dentist)
• Identifying Bias WS
Learning Target
CS10:• I understand how technology and science
can change over time. (9.1.1.1.7)CS11:• I can recognize the gradual development
and improvement of any scientific theory over time. (9.1.1.1.7)– I understand that theories build upon prior
scientific knowledge and discoveries.
Science as a Process
Scientific theories etc. can be proven wrong, but they can never be proven right with 100% certainty…
…So the Theory ▪ Exists until someone proves it wrong.or▪ Is improved upon by others.
Scientific Theory and Scientific Inquiry
• Observation leads to theory explaining it
• Theory leads to predictions consistent with previous observations
• Predictions of new phenomena are observed. If the observations agree with the prediction, more predictions can be made. If not, a new theory can be made or an old theory modified.
Each cycle around gets us closer to the truth
Scientific Theory and Scientific Inquiry
•This is how theories grow and develop.
•The whole cycle does not happen overnight, nor does it have to be the work of one person or group.
•Theories can and often do develop over generations.
•One scientist builds off the work of another
Science
Review…• Explain How the World/Universe Works• Answering Questions• Products: Models, Laws, Theories etc.
