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Problemistics - Problémistique - Problemistica
The Art & Craft of Problem Dealing
Experiment
Experiment: definition (W. I. B. Beveridge)
Experiment: definition (John Madge)
Experiment: definition (Abraham Kaplan)
Experiment: definition (Geoffrey Broadbent)
Experiment: difference observation - experimentation (John Stuart Mill)
Experiment: difference observation - experimentation (Claude Bernard)
Experiment: preliminary experiments (W. I. B. Beveridge)
Experiment: classification (Abraham Kaplan)
Experiment: classification and function (Abraham Kaplan)
Experiment: function (Galileo Galilei)
Experiment: function (John Ziman)
Experiment: experiment and preconceived ideas (Henri Poincaré)
Experiment: experiment and theory (Abraham Kaplan)
Experiment : variables (Deobold B. Van Dalen)
Experiment: list of possible variables (Deobold B. Van Dalen)
Experiment: characteristics (Deobold B. Van Dalen)
Experiment: components (Deobold B. Van Dalen)
Experiment: probability and truth (Deobold B. Van Dalen)
Experiment: limitations (W. I. B. Beveridge)
W. I. B. Beveridge, The Art of Scientific Investigation, Random House, New York, Third edition.
“An experiment usually consists in making an event occur under known conditions where as many extraneous influences as possible are eliminated and close observation is possible so that relationships between phenomena can be revealed.” (p. 20)
[1965] John Madge, The Tools of Social Science, Longmans, London, First published 1953
“... the experiment consists, in some form or another, of a comparison between two sets of circumstances, which exactly match each other in all respects except one.”
(Chapter 5, p. 255)
[1964] Abraham Kaplan, The Conduct of Inquiry. Methodology for Behavioural Science, Chandler Publishing Company, Scranton, Pennsylvania
“Basically, experimentation is a process of observation, to be carried out in a situation especially brought about for that purpose.” (p. 144)
“By experiment we are empowered to observe under rare and special circumstances of our own choosing; and we choose them in the hope of thereby enriching our experience.” (p. 147)
[1988] Geoffrey Broadbent, Design in Architecture, First Edition 1973
“The experiment ... is a set of controlled observations under artificial conditions in which certain variables are manipulated deliberately so as to confirm or disprove our hypotheses.” (Chapter 3, p. 57)
[1891] John Stuart Mill, A System of Logic, First Edition 1843
"The first and most obvious distinction between Observation and Experiment is, that the latter is an immense extension of the former. It not only enables us to produce a much greater number of variations in the circumstances than nature spontaneously offers, but, also, in thousands of cases, to produce the precise sort of variation which we are in want of for discovering the law of the phenomenon."
"But there is another superiority ... of instances artificially obtained ..."
"When we can produce a phenomenon artificially, we can take it, as it were, home with us, and observe it in the midst of circumstances with which in all other respects we are accurately acquainted."(Book 3, Chapter VII, § 3)
[1865] Claude Bernard, Introduction à l'étude de la médecine expérimentale
"On donne le nom d’observateur à celui qui applique les procédés d'investigation simples ou complexes, à l'étude de phénomènes qu'il ne fait pas varier et qu'il recueille, par conséquent, tels que la nature les lui offre.
On donne le nom d’expérimentateur à celui qui emploie les procédés d'investigation simple ou complexes pour faire varier ou modifier, dans un but quelconque, les phénomènes naturels et les faire apparaître dans des circonstances ou dans des conditions dans lesquelles la nature ne les lui présentait pas." (Chapter 1, § IV)
[1957] W. I. B. Beveridge, The Art of Scientific Investigation, Random House, New York, Third edition
“Apart from consideration of economy ... it is often better for the investigation to progress from one point to the next in stages, as the latter experiment may require modification according to the results of the earlier ones.” (pp. 21-22)
“One type of preliminary experiment is the ‘pilot’ experiment, which is often used when human beings or farm animals are the subjects. This is a small-scale experiment often carried out at the laboratory to get an indication as to whether a full-scale field experiment is warranted.
Another type of preliminary experiment is the ‘sighting’ experiment done to guide the planning of the main experiment. The so-called ‘screening’ test is also a type of preliminary experiment. This is a simple test carried out on a large number of substances with the idea of finding out which of them warrant further trial, for example as therapeutic agents.” (p. 22)
[1964] Abraham Kaplan, The Conduct of Inquiry. Methodology for Behavioural Science, Chandler Publishing Company, Scranton, Pennsylvania
"When the scientist intervenes in the context of behaviour as it is given, and for the specific purpose of experimentation, we may speak of a field experiment.
This may be contrasted with a laboratory experiment, in which the context as well as the behaviour pattern is subjected to controls."
“Plainly, the distinction is very much a matter of degree. Its usefulness depends largely on the extent to which the subject being experimented on is responsive to those features of the context that have been controlled.” (Chapter IV, p. 165)
[1964] Abraham Kaplan, The Conduct of Inquiry. Methodology for Behavioural Science, Chandler Publishing Company, Scranton, Pennsylvania
- Methodological experiments: they serve to develop or to improve some particular technique of inquiry. A certain type of methodological experiment is sufficiently important to deserve its own name: the pilot study, also known as ‘pretest’.
- Heuristic experiments: “designed to generate ideas, to provide leads for further inquiry or to open up new lines of investigation.” “A special kind of heuristic experiment may be called exploratory. It is frankly intended just to see what would happen if --." "An exploratory experiment may be conducted to determine a range of outcomes with the systematic variation of some parameter, as in fixing the optimal dosage of a drug. Or it may be conducted according to a trial-and-error pattern to exhaust some set of possibilities.”
- Fact-finding experiments: “Probably the most common experiments in actual scientific contexts are those we might call fact-finding, aiming at the determination of some particular magnitude or property of a relatively well-defined object or situation. This type of experiment is exemplified by the administration of an intelligence test or the conducting of an opinion poll.”
- Boundary experiments: “are explicitly associated with some set of laws and consist of fact-finding inquiries designed to fix the range of application of the laws, particularly with regard to extreme conditions.”
- Simulation experiments: “are experiments on a model; they are designed to learn what will happen under certain ‘real’ conditions related in a definite way to the experimental ones.” “We simulate when more realistic experiments are ... too costly, or physically or morally impossible, or when the real situation is too complex.” (from Chapter IV, pp. 148-151)
[1973] Galileo Galilei in Geoffrey Broadbent, Design in Architecture, Revised Edition 1988
“for I know ... that one concludent experiment sufficeth to batter to ground ... a thousand ... probable arguments.” (p. 56)
[1968] John Ziman, Public Knowledge
“Experiment bridges the gulf between the empirical and the theoretical.” (Chapter 3, p. 36)
[1968] Henri Poincaré, La Science et l'Hypothèse, First Published 1902
“On dit souvent qu’il faut expérimenter sans idée préconçue. Cela n’est pas possible; non seulment ce serait rendre toute expérience stérile, mais on le voudrait qu’on ne le pourrait pas. Chacun porte en soi sa conception du monde dont il ne peut se défaire si aisément. Il faut bien, par exemple, que nous nous servions du langage, et notre langage n'est pétri que d'ideés préconçues et ne peut l'être d'autre chose. Seulement ce sont des idées préconçues inconscientes, mille fois plus dangereuses que les autres.” (Chapter IX, p. 159)
English version: “It is often said experiments must be made without a preconceived idea. That is impossible. Not only would it make all experiment barren, but that would be attempted which could not be done. Everyone carries in his mind his own conception of the world, of which he cannot so easily rid himself. We must, for instance, use language; and our language is made up only of preconceived ideas and cannot be otherwise. Only these are unconscious preconceived ideas, a thousand times more dangerous than the others.”
[1964] Abraham Kaplan, The Conduct of Inquiry. Methodology for Behavioural Science, Chandler Publishing Company, Scranton, Pennsylvania
“There are scientists for whom theory is important only because of the new experiments it suggests, and others who view experimentation only as a procedure for generating and verifying theory.” (p. 146)
“[Theory] guides us in the decisions as to what to observe and under what conditions, what factors are worth investigating and which are to be controlled.” (p. 161)
[1979. First edition 1962] Deobold B. Van Dalen, Understanding Educational Research. An Introduction, McGraw-Hill Book Company, New York
“Because a hypothesis predicts that two or more variables are related, there are at least two main variables under consideration in an experiment:
the independent variable, X, which is manipulated purposively, and the dependent variable, Y, which is the presumed effect or consequent of the manipulation of the independent variable.” (p. 226)
“Obviously, you do not choose your variables at random or casually; rather, you choose them with extreme care, for such choices are among the crucial ones you must make. Previous experience with the phenomena and a careful analysis of the problem will suggest some clues.” (p. 228)
[1979, First edition 1962] Deobold B. Van Dalen, Understanding Educational Research. An Introduction, McGraw-Hill Book Company, New York
- Independent variable (presumed cause)
- Dependent variable (presumed effect)
- Extraneous variable (coincidently associated)
- Component variable (composed of several sub-variables)
- Intervening variable (intervening at some point in time)
- Antecedent variable (tracing the causal sequence one step back to a root cause)
- Suppressor variable (hidden variable concealing a relation)
- Distorter variable (misleading variable)
(Chapter 10, pp. 302-305)
[1979, First edition 1962] Deobold B. Van Dalen, Understanding Educational Research. An Introduction, McGraw-Hill Book Company, New York
“The key factor that distinguishes experimental studies from other types of research is that the investigators control the manipulation of X, the experimental variable, to ascertain whether X is related to the occurrence of a particular event, condition, or effect.”
“In historical and descriptive research, investigators observe evidence relating to an event, but they exercise no direct control over its occurrence because the event has already taken place or for other reasons cannot be manipulated.” (Chapter 9, p. 226)
[1979, First edition 1962] Deobold B. Van Dalen, Understanding Educational Research. An Introduction, McGraw-Hill Book Company, New York
- Independent Variable (X) or (X1) (X2) (X3)
- Dependent Variable (Y)
- Experimenter(s) (E) (Es)
- Subject(s) (S) (Ss)
- Experimental group (the one exposed to X)
- Control group (the one not exposed to X)
- Pre-test (T1) (administered before X is applied)
- Post-test (T2) (administered after X is applied).
- Mean (M)
- Population (Universe)
- Sample
(Chapter 9, p. 232)
[1979] Deobold B. Van Dalen, Understanding Educational Research. An Introduction, McGraw-Hill Book Company, New York, First edition 1962.
“Experimentation produces statements of probability. According to the rules of logic, one is never fully justified in inferring universal statements from single or numerous observations, for any conclusions drawn in this manner may turn out to be false.”
“In short, experimental statements are statistical inferences; they can attain a degree of probability only somewhere along a continuum between truth and falsity.”
“Certainty cannot be achieved through experimentation, but you should do everything practicable to reduce uncertainty.” (Chapter 9, p. 283)
[1957] W. I. B. Beveridge, The Art of Scientific Investigation, Random House, New York, Third edition
“Nevertheless, important as experimentation is in most branches of science, it is not appropriate to all types of research. It is not used, for instance, in descriptive biology, observational ecology or in most forms of clinical research in medicine.” (Chapter 2, p. 19)