Jump to navigation Jump to search “Experimental” redirects here. For the critical thinking research paper classification, see Experimental music. Even very young children perform rudimentary experiments to learn about the world and how things work.
An experiment is a procedure carried out to support, refute, or validate a hypothesis. Experiments provide insight into cause-and-effect by demonstrating what outcome occurs when a particular factor is manipulated. Experiments vary greatly in goal and scale, but always rely on repeatable procedure and logical analysis of the results. A child may carry out basic experiments to understand gravity, while teams of scientists may take years of systematic investigation to advance their understanding of a phenomenon. Experiments and other types of hands-on activities are very important to student learning in the science classroom. Experiments can raise test scores and help a student become more engaged and interested in the material they are learning, especially when used over time. Experiments typically include controls, which are designed to minimize the effects of variables other than the single independent variable.
This increases the reliability of the results, often through a comparison between control measurements and the other measurements. In the scientific method, an experiment is an empirical procedure that arbitrates competing models or hypotheses. An experiment usually tests a hypothesis, which is an expectation about how a particular process or phenomenon works. However, an experiment may also aim to answer a “what-if” question, without a specific expectation about what the experiment reveals, or to confirm prior results. If an experiment is carefully conducted, the results usually either support or disprove the hypothesis.
In engineering and the physical sciences, experiments are a primary component of the scientific method. In medicine and the social sciences, the prevalence of experimental research varies widely across disciplines. There are various differences in experimental practice in each of the branches of science. One of the first methodical approaches to experiments in the modern sense is visible in the works of the Arab mathematician and scholar Ibn al-Haytham. We should, that is, recommence the inquiry into its principles and premisses, beginning our investigation with an inspection of the things that exist and a survey of the conditions of visible objects. We should distinguish the properties of particulars, and gather by induction what pertains to the eye when vision takes place and what is found in the manner of sensation to be uniform, unchanging, manifest and not subject to doubt. According to his explanation, a strictly controlled test execution with a sensibility for the subjectivity and susceptibility of outcomes due to the nature of man is necessary.
It is thus the duty of the man who studies the writings of scientists, if learning the truth is his goal, to make himself an enemy of all that he reads, and, applying his mind to the core and margins of its content, attack it from every side. He should also suspect himself as he performs his critical examination of it, so that he may avoid falling into either prejudice or leniency. Thus, a comparison of earlier results with the experimental results is necessary for an objective experiment – the visible results being more important. English philosopher and scientist active in the 17th century, became an influential supporter of experimental science in the English renaissance. In the centuries that followed, people who applied the scientific method in different areas made important advances and discoveries. Experiments might be categorized according to a number of dimensions, depending upon professional norms and standards in different fields of study.
A good example would be a drug trial. An example that is often used in teaching laboratories is a controlled protein assay. Controlled experiments can be performed when it is difficult to exactly control all the conditions in an experiment. In this case, the experiment begins by creating two or more sample groups that are probabilistically equivalent, which means that measurements of traits should be similar among the groups and that the groups should respond in the same manner if given the same treatment. Once equivalent groups have been formed, the experimenter tries to treat them identically except for the one variable that he or she wishes to isolate. Human experimentation requires special safeguards against outside variables such as the placebo effect.
The goal of the experiment is to measure the response to the stimulus by a test method. In the design of experiments, two or more “treatments” are applied to estimate the difference between the mean responses for the treatments. Experiments can be also designed to estimate spillover effects onto nearby untreated units. The term “experiment” usually implies a controlled experiment, but sometimes controlled experiments are prohibitively difficult or impossible. In this case researchers resort to natural experiments or quasi-experiments. Field experiments are so named to distinguish them from laboratory experiments, which enforce scientific control by testing a hypothesis in the artificial and highly controlled setting of a laboratory.
Often used in the social sciences, and especially in economic analyses of education and health interventions, field experiments have the advantage that outcomes are observed in a natural setting rather than in a contrived laboratory environment. Fundamentally, however, observational studies are not experiments. By definition, observational studies lack the manipulation required for Baconian experiments. Observational studies are limited because they lack the statistical properties of randomized experiments. Even when experimental research does not directly involve human subjects, it may still present ethical concerns. For example, the nuclear bomb experiments conducted by the Manhattan Project implied the use of nuclear reactions to harm human beings even though the experiments did not directly involve any human subjects.
The experimental method can be useful in solving juridical problems. An Analysis of Frequency of Hands-on Experience and Science Achievement”. Journal of Research in Science Teaching. Fantastic realities : 49 mind journeys and a trip to Stockholm. Journal of the American Statistical Association. Cambridge handbook of experimental political science. A Philosophical Perspective on Alhazen’s Optics”.