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Week 1. Scientific method and research methodology PhD Seminar Authors: Niusvel Acosta Hussein López Advisors: Dr. Felipe Orihuela-Espina Dr. Manuel Montes y Gómez Contents 1. Scientific method i. ii. iii. iv. v. Introduction A brief history Steps Characteristics Hypothesis 2. Research methodology i. ii. iii. iv. v. vi. 21/07/2015 What is? Different approaches Thesis Types of scientific research Research process Scientific paper INAOE 2 Part I THE SCIENTIFIC METHOD (CLASSIC) 21/07/2015 INAOE 3 Introduction (1) In general, science aims at providing explanations of phenomena observed in nature and society. This explanation is offered in terms of relations between an observed phenomena (effect) as a consequence of its possible origin (cause). These relations are established by means of experimentation following the scientific method. i.e. experiments are central to science 21/07/2015 INAOE 4 Introduction (2) Purpose of Scientific Method: To build a representation of the world/nature/society that is accurate, reliable, consistent and not arbitrary Science is a rational activity operating according to some special method or methods. Alan Chalmers, in his book What is this Thing Called Science (1990) 21/07/2015 INAOE 5 Introduction (3) There exist an objective reality which is the same for everyone [Cotton and Sekula]. Reality exists as an absolute goal: facts are facts regardless of feelings, desires, hopes or fears of people. Ayn Rand, “mother” of objectivism “If your own private reality includes a law of gravity that is different from Newton's, any predictions you make with it are not going to match reality.” [http://www.physics.smu.edu/pseudo/SciMeth/] 21/07/2015 INAOE 6 Introduction (4) There exist [unchanging] laws by which the universe works [Cotton and Sekula]. These laws can be discovered (not invented) through experimentation These laws may however not deterministic; they might be stochastic. be Unchanging does not mean static! This becomes especially clear in social research as society evolves with time. 21/07/2015 INAOE 7 Introduction (5) Fact: A fact is an observation that has been confirmed repeatedly and that for all practical purposes it is accepted as true. Definition by the National Academy of Sciences "Everyone is entitled to his own opinion, but not his own facts.” Daniel Patrick Moynihan (1927-2003), Senador de los EEUU "Facts do not cease to exist because they are ignored.“ Aldous Huxley 21/07/2015 INAOE 8 A brief history The Greek naturalistic movement Inductive reasoning < 1600 DC > The nature of science 0 < 322 BC Deductive reasoning 21/07/2015 The scientific revolution INAOE > 1900 DC Deductive falsification 9 A brief (not exhaustive) history of the scientific method Aristoteles 384-322 BC: Aristotelic Empiricism Roger Bacon 1214-1294. Roger Bacon describes the cycle of observation, hypothesis, experimentation and verification ~700-1000. Arabs Alhacén, Al-Biruni and Avicena among others, develop different forms of experimentation and quantification to discriminate among competing theories Ibn al-Haytham , Abū Rayhān al-Bīrūnī, Ibn Sina Avicenna 21/07/2015 INAOE 1561–1626. Francis Bacon incorporates induction as a rational method to reach causality Francis Bacon 10 A brief (not exhaustive) history of the scientific method David Hume, John Stuart Mill, Charles Peirce Galileo Galilei 1564-1642. Galileo uses mathematical demonstration as a form to obtain valid scientific results 21/07/2015 S XIX. Several contributions from Hume (inductive reasoning), Mill (knowledge based on experience), Peirce (scheme for hypothesis testing and randomization) 1791-1867. Faraday demands intellectual honesty and criticism from peer (peer review) together with scrupulous documentation of experiments so that they can be reproduced. S XX, Popper (necessity for falsability), First computer simulation, Kuhn (paradigm and Incommensurability) Michael Faraday Karl Popper, Thomas Kuhn INAOE 11 Steps (1) The scientific method in a nutshell: 1. Observation of a phenomenon 2. Formulation of a hypothesis or plausible explanation of the phenomenon that might explain the observations 3. To carry out an experiment altering the conditions and measuring/observing the phenomenon under the changing environment 4. Confirmation (or refutation) of the hypothesis based on evidence (observations) collected during the experimentation 21/07/2015 INAOE 12 Steps (2) Figure from: [www.studyblue.com] 21/07/2015 INAOE 13 Characteristics (1) The scientific method is an effort: Collective of all scientists Individual research are unavoidably influence by personal and cultural bias. Standardized to minimize bias Consensus among the scientific community is a central demand [SwanbornPG1996] 21/07/2015 in INAOE empirical research. 14 Characteristics (2) The scientific method is an effort: Dynamic (time) It is subject to continuous revision. The hypothesis that has been hold across many observations might still be refuted at any time by new evidence (facts). "When the facts change, I change my mind. What do you do, sir?" Attributed to John Maynard Keynes Science is self-corrective. 21/07/2015 INAOE 15 Characteristics (3) The scientific method is an effort: Critic and creative Critical thinking is capable of deciding whether an statement is always true, partially true or false. Creative thinking permits developing unique and useful ideas worth of consideration. http://www.umich.edu/~elements/probsolv/strategy/crit-ncreat.htm Without these two thinkings we would be unable to formulate a hypothesis nor to confirm/refute them. 21/07/2015 INAOE 16 Characteristics (4) The scientific method is an effort: Skeptical It requires experimental evidence before doing or accepting an statement …but it admits assumptions (lacking evidence) based on previous knowledge about the phenomenon Skeptical does not mean denier (available evidence is never enough) Trust is of utmost importance among scientist. In principle, you trust that others researchers are being 21/07/2015 honest …yet you have to test/review/challenge their evidence. INAOE 17 Hypothesis (1) An hypothesis is a limited statement regarding cause and effect in specific situations. Criteria of hypothesis: They should be statements expressing the relation between two or more measurable variables. They should carry clear implications for testing the stated relations. 21/07/2015 INAOE 18 Hypothesis (2) Problems of omitting hypothesis: Ambiguity is major cause of referee/reader misunderstanding. Vagueness is major cause of poor methodology: inconclusive evidence; Unfocussed research direction. 21/07/2015 INAOE 19 Hypothesis (3) Exploration of Techniques: Invention of new technique, Investigation of technique, e.g. discovery of properties of, or relationships between, techniques. Extension or improvement of old technique, New application of a technique, to artificial or natural systems. Combine several techniques into a system. 21/07/2015 INAOE 20 Hypothesis (3) ¡YOU CAN’T DEMONSTRATE THAT A HYPOTHESIS IS CORRECT/TRUE! To have positive evidence supporting a hypothesis is not equivalent to demonstrate a hypothesis, let alone to confirm a fact. …with positive evidence you only increase your confidence in the hypothesis. The more experiments are made that result in evidence supporting your hypothesis, the bigger certainty you have on your hypothesis. 21/07/2015 INAOE 21 Hypothesis (4) Hypothesis Model Scientific thoery Law Fact 21/07/2015 INAOE 22 … considerations “In science, you encounter the disturbing fact that, if your ‘point of view’ does not agree with reality as determined by experiment through the scientific method, then your point of view is simply wrong.” [Cotton y Sekula, http://www.physics.smu.edu/pseudo/SciMeth/] 21/07/2015 INAOE 23 … considerations Having said that: It is acceptable that our point of view changes as sciences gathers more reliable evidence. …but that change must be guided by evidence. If a established theory (one that has passed many experiments) is in disagreement with new evidence, the theory has to be reviewed maybe even discarded as a description of reality It may still be valid within certain restrictions Classical example: Newton’s gravity laws. 21/07/2015 INAOE 24 Part II RESEARCH METHODOLOGY 21/07/2015 INAOE 25 What is known as research methodology? Ordered procedure which is followed to establish the meaning of the facts and phenomenon to which the scientific interest is directed for finding, demonstrating, refuting and providing a knowledge. It is a set of techniques and procedures whose primary purpose is to implement processes of picking, classifying and validating the data and experiences from reality, and from which can be build scientific knowledge. 21/07/2015 INAOE 26 Approaches of research methodology Qualitative, quantitative and hybrid: are based on the phenomenon observations and evaluations conclusions are achieved as results of this basis demonstrate the reality degree of the achieved conclusions check the conclusions reached and are able to generate new fundaments, based on the founded trends 21/07/2015 INAOE 27 Approaches of research methodology Qualitative: does not takes the hypothesis proof and numerical measurements neither. Is based on surveys, interviews, descriptions, researcher's view points, reconstructions of facts. Quantitative Hybrid 21/07/2015 INAOE 28 Approaches of research methodology Qualitative Quantitative: Is based on the numerical measurements Uses the observation to picking data and analyzes them to answer their research questions. is rather used in processes which can be measurable or quantifiable. Hybrid 21/07/2015 INAOE 29 Approaches of research methodology Qualitative Quantitative Hybrid: both concepts are integrated both processes are combined to reach a results in a superior form. 21/07/2015 INAOE 30 What is a thesis? A thesis is: Original (creative) and significant A record of research (so that it is reproducible) A critical survey Reviews existing work Discusses results in terms of current evidence The conclusion of a set of coherent experiments for testing certain hypothesis about a certain phenomenon of interest. 21/07/2015 INAOE 31 What is a thesis? A good thesis includes: Who? – A phenomenon being studied What? – A clear message, hypothesis and/or claim …and evidence for this Why? – A motivation and justification How? - Methodology When (time) and where (spatial)? Constraints, limitations and discussion 21/07/2015 INAOE – 32 Common pitfalls while doing a thesis Being too ambitious Stopping reading after an initial survey of related work Think that there is no related work You simply have not search thorough enough Underestimate or overestimate the relevance or significance of the research 21/07/2015 INAOE 33 Some tips Keep (organized) record of everything; Notes of your ideas Notes on read papers Set up and results of your experiments, but also distractions, artifacts, etc. Documentation of programs and code Focus on principles and foundations, not on implementation and performance Never, ever delete a file/data Keep different versions This helps to remember, but also allows you to go back if something goes wrong 21/07/2015 INAOE 34 Some tips Read and write! For a good understanding, reading a paper once is often not enough. It is fine to fail It is research, so you may guess what’s going to happen, but cannot be sure. Admit ignorance …make questions, even if you think: (i) the expert is 21/07/2015 going to laugh at you, or (ii) what you are asking is obvious for everyone else. “Quien pregunta es tonto 5 mins., quien no pregunta es tonto toda la vida” Spanish saying INAOE 35 Methods and types of scientific research Methods and techniques: Exploratory Descriptive Correlational Explanatory Types: Academic research (basic) Translational research Applied research 21/07/2015 INAOE 36 Research process Problem Development of theoretical framework Hypotheses formulation Experimental design and data collection Sample selection Research design selection In case of be necessary Data analysis and conclusions 21/07/2015 INAOE 37 Scientific paper Concluding with persuasive conclusions and citations Interesting discussion with clear figures Appropriate abstract and keywords Engaging paper Clear and reproducible presentation of the proposal 21/07/2015 Starting with a brief and attractive tittle Presentation of the related work INAOE Introduction suitable for target audience Lucid motivation and research description 38 References Bundy, A. et al., The Researchers Bible. Teaching Paper No. 4, Department of Artificial Intelligence, University of Edinburgh, 1986 Keppel, G. Design and analysis: A researcher's handbook. Prentice-Hall, Inc, 1991 Bundy, A. The Need for Hypotheses in Informatics, University of Edinburgh http://www.inf.ed.ac.uk/teaching/courses/irm/notes/hypotheses.html The scientific method: Cotton J and Sekula S. The Scientific Method http://www.physics.smu.edu/pseudo/SciMeth/ http://teacher.nsrl.rochester.edu/phy_labs/AppendixE/AppendixE.html Williams, J. A brief history of the scientific method, School Science Review (2007) Ziemski, S. The typology of scientific research, Journal for General Philosophy of Science 6 (2):276-291 (1975) Ziemski, S. Two Types of Scientific Research, Journal for General Philosophy of Science 10 (2):338-342 (1979) Chapman, D. (Editor). How to do Research at the MIT AI Lab, Massachusetts Institute of Technology Artificial Intelligence Laboratory (1988) 21/07/2015 INAOE 39 THANKS, QUESTIONS? 21/07/2015 INAOE 40