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Scientific method


Syllabus (under construction)

When can correlation equal causation?

Data needs an interpretation to have meaning

Good hypothesis vs bad hypothesis

Science is not a belief or a position.

Science is a method that allows us to test claims. We ask and refine testable questions that lead to explanations of how the world works.

Consensus is not a part of the scientific method – rather, consensus is a consequence of it.

Consensus arises when a large body of scientific literature points towards similar conclusions.

Is there such a thing as “the scientific method?” Yes, but it isn’t quite what you may have learned in middle school. Consider this classic sequence.

Ask a Question Research Hypothesis flowchart

But it doesn’t work like a recipe:

How does science really work?

  • scientists continually share ideas with peers.

  • this often causes us to change our hypothesis.

  • Outside of science, changing ideas is called “flip flopping”

  • But in science, changing one’s position based on evidence is a strength.

  •  Creativity and imagination abound at every step

  • The scientific method is not a linear path

    Neil Degrasse Tyson

    Neil Degrasse Tyson

    I. The “first step” of the scientific method?

    There’s no recipe. Once in a while, we observe something which contradicts our view of the world. Some practical problem exists, or there is a surprising observation – and because we have curiosity,  we ask “how this can be?”

    Scientific Method coming up with an idea

    The University of California Museum of Paleontology, Berkeley (c)

    II. Only works for scientific questions.

    Science doesn’t answer questions about value, beauty, meaning or ethics. Science does not address supernatural claims.

    Science has limits: Here is what science does not do.

    III. Science is not a belief or a position

    Science is a process used to approach claims – to see if the claim is correct or not. We approach claims skeptically: That doesn’t mean that that we don’t believe anything. Rather, it means we don’t accept a claim unless we are given compelling evidence. Skepticism is a provisional approach to claims.

    skeptic no amount of belief

    Calvin here clearly needs to come up with a testable hypothesis:

    calvinandhobbes toast

    IV. How to create a hypothesis

    Suppose that your car will not start. Create a hypothesis.
    “My car does not start because the battery is low.”


    * If the headlight switch was left on for a long time, this would result in a battery drain.

    * The starter will make a certain type of sound if the battery is dead (many of you will know what I am talking about here.)

    • If the battery is dead, the voltage across the battery terminals will be much lower than normal.

    Experiment: Test to see if predictions are verified or refuted

    * Check whether the lights were left on.

    * Insert the key and turn it; listen to the sound of the engine.

    * With the right device, check the voltage of the battery.

    Evaluate the results:
    If predictions are verified, then our hypothesis was confirmed.
    If predictions are refuted then our hypothesis must be rejected. Then we must come up with another hypothesis, e.g.  “The starter is broken”, or “Out of gas”, etc.


    V. Writing a Hypothesis

    Your hypothesis must be something you can test.

    “If I do [this], then [that] will happen.”

    If I [give flower seeds an organic fertilizer] then [they will sprout faster than those fed a synthetic fertilizer].


    BAD – Planets move around the Sun at different speeds, because different angels push them.

    GOOD – Planets move around the Sun at different speeds, because at different distances from the Sun, they experience a different amount of pull from the Sun’s gravity.

    There is no way to test the first statement; therefore it is not a scientific hypothesis.

    VI. Peer Review


    Scientists describe their methods and results: They publish in peer‑reviewed journals. Others can then repeat the work, and offer constructive criticism.

    If others get the same result, then we can say with a higher degree of certainty that our hypothesis is correct,

    If others get different results, then something might be wrong or overlooked.

    Peer review is necessary – only by working with others can we be sure that our results are trustworthy.

    VIII Numbers have no meaning by themselves.

    Data needs an interpretation to have meaning

    IX. We can’t always trust our senses

    Why do we need science? We often perceive things that are not really there:

    Apophenia /æpɵˈfiːniə/ is a human tendency of perceiving patterns or connections in random or meaningless information.

    Pareidolia (/pærɨˈdoʊliə/ parr-i-doh-lee-ə) is the visual or auditory form of apophenia. People may perceive patterns in images and sounds, that really are not there. Common examples are perceived images of animals, faces, or objects in cloud formations; the “man in the moon”; and claims of hidden messages within recorded music played in reverse.

    The Rorschach inkblot test is a famous example of psychologists attempting to use pareidolia, in an attempt to gain insight into a person’s mental state. (However it should be noted that the Rorschach test itself is no longer widely considered to produce useful informationn.)

    The clustering illusion is the tendency to erroneously consider the inevitable “streaks” or “clusters” arising in small samples from random distributions to be non-random.

    Confirmation bias is the tendency to search for, interpret, and favor information in a way that confirms one’s beliefs, while giving disproportionately less attention to information that contradicts it.

    Four examples of questions we can use science to answer

    Critical thinking paper!

    Learning Objectives

    2016 Massachusetts Science and Technology/Engineering Standards
    Students will be able to:
    * plan and conduct an investigation, including deciding on the types, amount, and accuracy of data needed to produce reliable measurements, and consider limitations on the precision of the data
    * apply scientific reasoning, theory, and/or models to link evidence to the claims and assess the extent to which the reasoning and data support the explanation or conclusion;
    * respectfully provide and/or receive critiques on scientific arguments by probing reasoning and evidence and challenging ideas and conclusions, and determining what additional information is required to solve contradictions
    * evaluate the validity and reliability of and/or synthesize multiple claims, methods, and/or designs that appear in scientific and technical texts or media, verifying the data when possible.

    A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas (2012)
    Implementation: Curriculum, Instruction, Teacher Development, and Assessment
    “Through discussion and reflection, students can come to realize that scientific inquiry embodies a set of values. These values include respect for the importance of logical thinking, precision, open-mindedness, objectivity, skepticism, and a requirement for transparent research procedures and honest reporting of findings.”

    Next Generation Science Standards: Science & Engineering Practices
    ● Ask questions that arise from careful observation of phenomena, or unexpected results, to clarify and/or seek additional information.
    ● Ask questions that arise from examining models or a theory, to clarify and/or seek additional information and relationships.
    ● Ask questions to determine relationships, including quantitative relationships, between independent and dependent variables.
    ● Ask questions to clarify and refine a model, an explanation, or an engineering problem.
    ● Evaluate a question to determine if it is testable and relevant.
    ● Ask questions that can be investigated within the scope of the school laboratory, research facilities, or field (e.g., outdoor environment) with available resources and, when appropriate, frame a hypothesis based on a model or theory.
    ● Ask and/or evaluate questions that challenge the premise(s) of an argument, the interpretation of a data set, or the suitability of the design

    MA 2016 Science and technology

    Appendix I Science and Engineering Practices Progression Matrix

    Science and engineering practices include the skills necessary to engage in scientific inquiry and engineering design. It is necessary to teach these so students develop an understanding and facility with the practices in appropriate contexts. The Framework for K-12 Science Education (NRC, 2012) identifies eight essential science and engineering practices:

    1. Asking questions (for science) and defining problems (for engineering).
    2. Developing and using models.
    3. Planning and carrying out investigations.
    4. Analyzing and interpreting data.
    5. Using mathematics and computational thinking.
    6. Constructing explanations (for science) and designing solutions (for engineering).
    7. Engaging in argument from evidence.
    8. Obtaining, evaluating, and communicating information.

    Scientific inquiry and engineering design are dynamic and complex processes. Each requires engaging in a range of science and engineering practices to analyze and understand the natural and designed world. They are not defined by a linear, step-by-step approach. While students may learn and engage in distinct practices through their education, they should have periodic opportunities at each grade level to experience the holistic and dynamic processes represented below and described in the subsequent two pages… http://www.doe.mass.edu/frameworks/scitech/2016-04.pdf

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