Frequently Asked Questions About How Science Works - Understanding Science (2023)

What is the scientific method?

The "scientific method" is traditionally presented in the first chapter of science textbooks as a simple, linear, five- or six-step procedure for conducting scientific inquiry. Although the scientific method captures the core logic of science (testing ideas against evidence), it misrepresents many other aspects of the true scientific process—the dynamic, nonlinear, and creative ways in which science is actually done. In fact, the Scientific Method more accurately describes how science is summarizedafter the fact- in textbooks and journal articles - than how scientific research is actually conducted. Teachers may require students to use the scientific method format to write down the results of their investigations (egQuestion, background information, hypothesis, study design, data analysis,AndDiploma), although the process the students went through in their investigations may have involved many iterations of questions, background research, data collection and data analysis, and although the students' "conclusions" will always be tentative. To learn more about how science really works and to see a more detailed representation of this process, visitThe real process of science.

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Why do scientists often seem hesitant in their explanations?

Scientists often seem cautious about their explanations, aware that those explanations could change as new evidence or perspectives come to light. When scientists write about their ideas in journal articles, they are expected to carefully analyze the evidence for and against their ideas and to explicitly address alternative explanations for what they observe. Because they are trained to do so for their scholarly writing, scholars often do the same when discussing their ideas with the press or a wider audience. Unfortunately, this means they are sometimes misinterpreted as wishy-washy or unsure of their ideas. Worse still, ideas supported by masses of evidence are sometimes dismissed by the public or the press because scientists talk about those ideas in tentative terms. It is important that the public recognize that while preliminaryness is a fundamental characteristic of scientific knowledge, scientific ideas supported by evidence can be trusted. To learn more about makeshifts in science, visit our Description pagehow science builds knowledge. To learn more about how this provisionalism can be misinterpreted, visit a section of theScientific Toolbox.

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Why is peer review useful?

Peer review helps to ensure the quality of published scientific work: that the authors did not ignore any key ideas or evidence, that the study was designed fairly, that the authors evaluated their results objectively, etc. This means that even if you are using the If you are not familiar with the research presented in a particular peer-reviewed study, you can be confident that it meets certain standards of scientific quality. This also saves scientists time to keep up to date with advances in their fields by weeding out untrustworthy studies. Peer-reviewed work is not necessarily accurate or conclusive, but it does meet the standards of scholarship. To learn more, visitquestion science.

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What is the difference between independent and dependent variables?

In an experiment, the independent variables are the factors that the experimenter manipulates. The dependent variable is the result of interest - the result that depends on the experimental design. Experiments are set up to learn more about how the independent variable affects or does not affect the dependent variable. For example, if you are testing a new drug to treat Alzheimer's disease, the independent variable might be whether or not the patient received the new drug, and the dependent variable might be how well participants do on memory tests. On the other hand, to study how the temperature, volume, and pressure of a gas are related, you could set up an experiment where you change the volume of a gas while keeping the temperature constant and see how that affects that of the gas's pressure. In this case, the independent variable is the volume of the gas and the dependent variable is the pressure of the gas. The temperature of the gas is a controlled variable. To learn more about experimental design, visitFair testing: A do-it-yourself guide.

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What is a control group?

In scientific testing, a control group is a group of people or cases that is treated in the same way as the experimental group, but is not exposed to the experimental treatment or factor. The results of the experimental group and the control group can be compared. When the control group is treated very similarly to the experimental group, this increases our confidence that any difference in outcome is caused by the presence of the experimental treatment in the experimental group. For example, visit our detourFair examinations in the field of medicine.

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What is the difference between a positive and a negative control group?

A negative control group is a control group that is not exposed to any experimental treatment or any other treatment that is expected to have an effect. A positive control group is a control group that is not exposed to the experimental treatment but is exposed to another treatment known to produce the expected effect. These types of controls are particularly useful for validating the experimental procedure. For example, imagine you want to know if lettuce contains bacteria. You set up an experiment where you wipe lettuce leaves with a swab, wipe the swab on a bacterial growth plate, incubate the plate, and see what grows on the plate. As a negative control, you can simply wipe a sterile swab over the growth plate. You would not expect bacterial growth on this plate, and if you do, it is an indication that your swabs, plates, or incubator are contaminated with bacteria that could affect the results of the experiment. As a positive control, you can blot any bacterial colony present and wipe it on the growth plate. In this case youwouldExpect bacterial growth on the plate, and when it doesn't, this is an indication that something in your setup is preventing bacterial growth. Perhaps the growth plates contain an antibiotic or the incubator is set at too high a temperature. Failure of either the positive or negative control to produce the expected result indicates that the investigator should reconsider their experimental approach. To learn more about experimental design, visitFair testing: A do-it-yourself guide.

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What is a correlation study and how is it different from an experimental study?

In a correlation study, a scientist looks for associations between variables (e.g., are people who eat lots of vegetables less likely to have a heart attack than others?) without manipulating any variables (e.g., without asking a group of people to eat more or less vegetables than usual). In a correlation study, researchers may be interested in any type of statistical association—a positive relationship between variables, a negative relationship between variables, or a more complex one. Correlation studies are used in many fields (e.g. ecology, epidemiology, astronomy, etc.), but the term is often associated with psychology. Correlational studies are often discussed in contrast to experimental studies. In experimental studies, researchers manipulate one variable (e.g. by asking one group of people to eat more vegetables and asking a second group of people to eat as usual) and study the effects of this change. When well designed, an experimental study can tell a researcher more about the cause of an association than a correlational study of the same system. Despite this difference, correlational studies still provide important evidence for testing ideas and often serve as inspiration for new hypotheses. Both types of study are very important in science and rely on the same logic to relate evidence to ideas. To learn more about the basic logic of scientific arguments, visitThe core of science.

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What is the difference between deductive and inductive reasoning?

Deductive reasoning involves logical extrapolation from a set of premises or hypotheses. You can think of it as a logical "if-then" reasoning. IF, for example, an asteroid hits Earth, and IF iridium is more abundant in asteroids than in the Earth's crust, and IF nothing further happens to the asteroid's iridium thereafter, THEN there will be an increase in iridium levels at the Earth's surface. The THEN statement is the logical consequence of the IF statements. Another case of deductive reasoning involves reasoning from a general premise or hypothesis about a particular case. Based on the idea that all living things are made up of cells, we could do that, for examplederivethat a jellyfish (a concrete example of a living being) has cells. Inductive reasoning, on the other hand, involves generalization based on many individual observations. For example, a scientist sampling rock strata from the Cretaceous-Tertiary (KT) boundary in many different locations around the world can always observe an increase in iridiuminducethat all KT interfaces have an iridium tip. The logical leap from many individual observations to an all-encompassing statement is not always justified. For example, it's possible that somewhere in the world there is a KT boundary layer without the iridium tip. However, many individual observations often strongly suggest a more general pattern. Deductive, inductive, and other types of reasoning are all useful in science. It's more important to understand the logic behind these different ways of reasoning than to worry about what they're called.

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What is the difference between a theory and a hypothesis?

Scientific theories are broad explanations for a wide range of phenomena, while hypotheses are proposed explanations for a fairly narrow group of phenomena. The difference between the two is mainly in width. Theories have broader explanatory power than hypotheses and often integrate and generalize many hypotheses. To be accepted by the scientific community, both theories and hypotheses must be supported by many different lines of evidence. However, both theories and hypotheses can be changed or overturned when warranted by new evidence and perspective.

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What is a null hypothesis?

A null hypothesis is usually a statement that claims there is no difference or association between variables. The null hypothesis is a tool that allows certain statistical tests to be used to find out whether another hypothesis of interest is likely to be true or not. For example, if you are testing the idea that sugar makes children hyperactive, your null hypothesis might be that there is no difference in the amount of time children who have previously been given a sugary drink and children who have been given a sugar substitute sit can still. After making your observations, you would then perform a statistical test to determine if there is a significant difference between the two groups of children in terms of the amount of time they sit still.

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What is Occam's Razor?

Occam's Razor is an idea with a long philosophical history. Today the term is often used to refer to the principle of parsimony - that when two explanations fit the observations equally well, a simpler explanation should be preferred to a more complicated and complex explanation. Put another way, Occam's razor suggests that, other things being equal, a simple explanation should be preferred to an explanation that requires more assumptions and sub-hypotheses. VisitCompeting Ideas: Other Considerationsto read more about thrift.

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What does science say about spirits, ESP and astrology?

Rigorous and well-controlled scientific research¹researched and found these issuesNOEvidence supporting their usual interpretations as natural phenomena (i.e. spirits as apparitions of the dead, ESP as the ability to read minds, and astrology as the influence of celestial bodies on human personalities and affairs) - although, of course, different people interpret these subjects in different ways. Science can only study such phenomena and explanations if they are viewed as part of the natural world. To learn more about the differences between science and astrology, visitAstrology: is it scientific?To learn more about the nature and types of questions and phenomena that science can study, visitwhat is naturalTo learn more about how science is approaching ESP, visitESP: What can science say?

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Has science had a negative impact on people or the world in general?

Knowledge generated by science has had many effects that most would classify as positive (e.g. enabling people to treat diseases or communicate instantly with people around the world); It also has some impacts that are often seen as negative (e.g. allowing people to build nuclear weapons or polluting the environment through industrial processes). However, it is important to remember that the process of science and scientific knowledge is different from the uses that people put that knowledge to. For example, we have learned a lot about deadly pathogens through the process of science. This knowledge could be used to design new drugs to protect humans from these pathogens (which most would consider a positive outcome), or it could be used to build biological weapons (which many would consider a negative outcome). And sometimes the same application of scientific knowledge can have both positive and negative effects. For example, research in the first half of the 20th century enabled chemists to create pesticides and synthetic fertilizers. Proponents argue that the spread of these technologies prevented widespread famine. However, others argue that these technologies have done more harm than good to global food security. Scientific knowledge in itself is neither good nor bad; However, people can use this knowledge in ways that have either positive or negative effects. In addition, different people may make different judgments about whether the overall impact of a particular scientific finding is positive or negative. To learn more about applying science, visitWhat has science done for you lately?

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