IMPORTANCE OF PROBLEM FORMULATION AND HYPOTHESIS TESTING IN SCIENTIFIC RESEARCH. Dr Zafar A Reshi

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1 IMPORTANCE OF PROBLEM FORMULATION AND HYPOTHESIS TESTING IN SCIENTIFIC RESEARCH Dr Zafar A Reshi Department of Botany, University of Kashmir, Srinagar zreshi@yahoo.com

2 My personal experience is that a researcher after completing his/ /her research programme invariably: is not satisfied with his/her work feels he/she cou uld have done better thinks that he/she has wasted time, energy, resources etc, and thinks that given another opportunity, he/she would do the same work differently and more appropriately that too in less time. is disappointed.

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4 Goals of Science: Seek truth or create knowledge Science is the pursuit of truth, of explanation, prediction, and control a phenomenon. Truth obtained from the scientific method contains both logic and evidence that are consistent with each other. Science is about the creation of knowledge, not the application o knowledge. Science cannot settle debate about values (good or bad, right o wrong, e.g. stem cell research) objectivity. Ultimate goal of science is to better the human condition. 4

5 5 What is Science Science (from Latin scientia, meaning "knowledge ) is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about nature and the universe. This knowledge is determined through the scientific method by experiments and observations, and may take the form of scientificc facts, scientific models, or scientific theories.

6 Branches of science and the hierarchy of science and the scale of the universe

7 7 Epistemology (nature and scope of knowledge) Reality: Threee views Premodern: Only one reality, no individual experience matters or allowed. Modern: There is an objective reality (e.g., the temperature) but we have different subjective experience of it (e.g., warm, cold). Agreement in subjective experiences could indicate objective reality. Postmodern: No objective reality, only images of reality or subjective experiences, and all are true. Agreement is neither necessary nor desirable to define reality.

8 In order to generate seek truth or knowledge Scientific metho od has to be followed

9 Whether scientific research is.. Empirical, factual or descriptive or Non-empirical, formal or theoretical

10 Ibn al-haytham (Alhazen n, ), is considered the father of the scientific method. According to Shmuel Sambursky, his emphasis has been on seeking truth: Modern science owes its present flourishing state to a new scientific method which was fashioned by Galileo Galilei ( )" Morris Kline

11 Scientific method is based on Deductive reasoning...we begin with supplied information, called premises, and draw conclusions on the basis of that information. Inductive reasoning...we begin with specific observations from which we seek to draw a conclusion or discover unifying rule or general principle.

12 Examples of deductive reasoning: All apples are fruits, all fruits grow on trees; therefore, all apples grow on trees. Since all humans are mortal, and I am a human, then I am mortal. All dolphins are mammals, all mammals have kidneys; therefore all dolphins have kidneys. The Earth is a planet, and all planets orbit a sun, therefore the Earth orbits a sun. All birds have feathers and robins are birds, so robins have feathers.

13 Examples of inductive reasoning: Robert is a teacher. All teachers are nice. Therefore, it can be assumed that Robert is nice. All students that have been taught by Mrs. Smith are right handed. So, Mrs. Smith assumes that all students are right handed. Jennifer leaves for school at 7:00 a.m. and is on time. Jennifer assumes, then, that she will always be on time if she leaves at 7:00 a.m. All observed basketball players are tall, so all basketball players must be tall. All observed brown dogs are small dogs. Therefore, all small dogs are brown.

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17 Scientific methodology has been practiced in som form for at least one thousand years. Because the scientific method is a feedback loop of induction an deduction, it often isn't possible to determine where the proces has started.

18 Scientific method Generally, research is understood to follow a certain structural process. Though order of step may vary depending on the subject matter and researcher, the following steps are usually pa of most formal research, both basic and applied: Problem formulation Hypothesis testing Conceptual definition Operational definition Data collection Analysis of data Data interpretation Test, revising of hypothesis Conclusion

19 Formulating the research problem is, in itself, a BIG problem. The mere formulation of a problem is far more essential than its solution, which may be merely a matter of mathematical or experimental skill. To raise new questions, new pos ssibilities, to regard old problems from a new angle requires creative imagination and marks real advances in science. Albert Einstein

20 The Research Problem It should be clear, concise, and manageable. The problem is basically a gap between what is and wha ought to be. A problem exists when theree is an absence of information resulting in a gap in knowledge; when there are contradictory results; and when a fact exists and you intend to make your study explain it. When a research is conducted to solve the problem as Tejero (2004 puts it, a gap is filled and new knowledge is created.

21 Problem formulation: a process It is an iterative process. You might switch many times between checking the literature to see if your idea is relevant and refining the problem formulation, back to se earching the literature with new ideas, etc. It takes a long time to develop a precise and specific problem formulation.

22 Characteristics of a Good Research Problem A good research problem as presented by Tejero (2004) is characterized as follows: 1. A good problem should be of great interest to the researcher. 2. A good problem should be novel. The research topic should be something new so that one can be sure that it really contributes to the formation of new knowledge and not just a mere repetition of what has been done already. 3. It should lend itself to complex research designing. 4. It should be completed in the allotted time desired. 5. It should not carry ethical or moral impediments.

23 Working through these steps pre-supposes a reasonable level of knowledge the broad subject area within whichh the study is to be undertaken. Witho such knowledge it is difficult to clearly and adequately dissect a subject area Step 1 Identify a broad field or subject area of interest to you Step 2 Dissect the broad area into sub areas. Step 3 Select what is of most interest to you. Step 4 Raise research questions. Step 5 Formulate objectives. Step 6 Assess your objectives. Step 7 Double check.

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25 What is a Hypothesis? Hypothesis is consideredd as the principal instrument i research. Hypothesis may be defined as a proposition or a set o propositions set forth as an explanation for the occurrence o some specified group of phenomenon either asserted mere as a provisional conjecture to guide some investigation o accepted as highly probable in the light of established facts. Research hypothesis is a predictive statement capable o being tested by a scientificc method.

26 Characteristics of a hypothesis Hypothesis should be clear and precise. It should be capable of being tested. Hypothesis should state relationship between variable, if happens to be a relational hypothesis. Hypothesis should be limited in scope and must be specific. Hypothesis should be stated, as far as possible, in most simpl terms. Hypothesis should be consistent with most known facts. Hypothesis should be amenable to testing within a reasonabl time. Hypothesis must explain the facts that gave rise to the need fo explanation.

27 Hypothesis Testing In order to reach an objective decision as to whether a particular hypothesis is confirmed by a set of data, we must have an objective procedure for either rejecting or accepting that hypothesis. Objectivity is emphasized because one of the requirements of the scientific method is that one should arrive at scientific conclusions by methods which are public and which may be repeated by other competent investigators.

28 Steps involved in Hypothesis Testing i. Stating the null hypothesiss ii. Choosing a statistical testt (with its associated statistical model) for testin the null hypothesis iii. Specifying the significance level and a sample size iv. Finding the sampling distribution of the test statistic under the nu hypothesis v. Defining the region of rejection vi. Computing the value of test statistic using the data obtained from th sample(s) and making a decision based on the value of the test statistic an the predefined region of rejection

29 Null hypothesis: The first step in the decision-making procedure is to state the null hypothesis Null hypothesis is usually denoted by H 0. The null hypothesis is a hypothesis of no difference. It is usually formulated for th he express purpose of being rejected. If it is rejected, the alternativee hypothesis H 1 may be accepted. The alternative hypothesis is the operational statement of the experimenter s research hypothesis. The research hypothesis is the prediction derived from the theory under test. When we want to make a decision about differences, we test H 0 agains H 1. H 1 constitutes the assertion that is accepted if H 0 is rejected.

30 Example of null and alternative hypothesis Null Hypothesis (H 0 ) = Attending Refresher Course has no effect on the performance of teachers Alternative Hypothesis (H 1 ) = Attending Refresher Course has a positive effect on the performance of teachers

31 The choice of the statistical test: The field of statistics has developed to the extent that we now have, for almost all research designs, alternative statistical tests which might be used in order to come to a decision about a hypothesis. The nature of the data collected largely determines the test criterion to be used.

32 The level of significance and the sample size: When the null hypothesis and alternative hypothesis have bee stated, and when the statistical test appropriate to the proble has been selected, the next step is to specify a level significance (α) and to select a sample size (n). Common values are 0.05 and There are two types of errors which may be made in arriving at a decisi about H o. The first, the Type I error, is to reject H o when in fact it is true. The secon the Type II error, is to accept H o when in fact it is false.

33 (iv) The sampling distribution: Sampling distributions represent a troublesome topic for many students. However, they are important because they are the basis for making statistical inferences about a population from a sample. It is that distribution we would get if we took all possible samples of the same size from the same population, drawing each randomly and workout a frequency distribution of the statistic computed from each sample. One problem sampling distributions solve for us is to provide a basis for using samples to make inferences about populations.

34 (v) The region of rejection: The region of rejection consists of a set of possible values whic are so extreme that when H o is true, the probability is very smal The probability associated with any value in the region o rejection is equal to or less tha anα.

35 (vi) The decision: If the statistical test yields a value which is in the region of rejection, we reject H o.

36 State H o and H 1 Specify the level of significance Decide the correct sampling distribution Sample a random sample(s) and workout an appropriate value fromthesampledata Calculate the probability that sample result would diverge as widely as it has from expectations, if H o were true. Is this probability equal to or smaller than α value in case of one-tailed test and α/2 in case of two-tailed test? Yes Reject H o No Accept H o Flow diagram of Hypothesis Testing

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38 Epilogue Being a good scientist requires patience, perseverance, imagination, curiosity, a skepticism; the essence of science is to doubt without adequate proof. Science also requires knowing how to make and interpret observations (whi presupposes a broad point of view), how to ask the right questions, how to theori without getting lost in the details, an nd knowing when to do experiments and app statistical tests. Recognition of one s work is desirable but should not be the primary goal, a publishing papers should be used primarily as a test of the scientist s ability to purs good science. The whole of science is nothing more than a refinement of everyday thinking. - Albert Einste

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40 How is research defined... Martin Shuttleworth --- "In the broadest sense of the word, resear includes gathering of data, information and facts for the advancement knowledge." Creswell --- "Research is a process of steps used to collect and anal information to increase our understanding of a topic or issue". It consists three steps: Pose a question, collect data to answer the question, and pres an answer to the question Research is any systematic investigation, with an open mind, to establish nov facts, solve new or existing problems, prove new ideas, or develop new theories Research is a process of collecting, analyzing and interpreting information answer questions.

41 But to qualify as research, the process must have certain characteristics: it must, as far as possible, be: Controlled Rigorous Systematic Valid and verifiable Empirical, and Critical

42 Controlled: The concept of control implies that, in exploring causality in relati to two variables (factors), a study should be set-up in a way that minimiz the effects of other factors affecting the relationship. Rigorous-scrupulous in ensuring that the procedures followed to find answers questions are relevant, appropriate and justified. Systematic- implies that the procedure adopted to undertake an investigati followed a certain logical sequence. Valid and verifiable- this concept implies that whatever you conclude on t basis of your findings is correct and can be verified by you and others. Empirical- this means that any conclusions drawn are based upon hard eviden gathered from information collected from real life experiences observations. Critical- critical scrutiny of the procedures used and the methods employed crucial to a research enquiry. The process of investigation must be foolpro and free from drawbacks. The process adopted and the procedures used mu be able to withstand critical scrutiny.

43 Because the scientific method is a feedback loop of induction and deduction, it often isn't possible to determine where the process ha started, but a common starting point is used here: 1. Observation: We observe something about the world and obtained through any or all of our senses; it 2. Repetition: A single observation has little long-term value, so more observations are necessary. New observations are obtained deliberately as part of an effort to confirm or refute the initia observation. Observations can be stated in the form of a question or problem. 3. Induction: arrive at new knowledge. This information might b may come through intentional efforts or accidentally After arranging and considering our observations, we create a general principle to describe wha happened and, more importantly, explains why it happened. This principle, called a hypothesis should be framed as broadly as possible.

44 4. Deduction: To see if our hypothesis is correct, we need to create deductions phrased as predications in the form "if principle P is true, then X should occur or fact F should be true." 5. Testing: Once we have predictions, we need to collect more observations by testing them. We need to determine if some fact (F) is already tr rue or if some event (E) occurs or can be caused to occur. 6. Induction (again): After we produce more observations, we need to look at our general principle again. If our predictions were true, our hypothesis is stronger; if this is successfully repeated multiple times, the hypothesis may be called a 'scientific theory.' If our predications failed, there are three possibilities: our theory was mistaken and we need to reformulate it; our deductions from the theory were mistaken and we need reconsider our understanding of it; or our experiments were flawed and we need to try again.

45 45 Normal Science based on the modern view of reality Normal science is empirical sciencee data, evidences or observations are necessary to support theory. Determination of significant fact, matching of facts with theory, and articulation of theory basic paradigm of normal science that we accept. Research based on shared paradigm is committed to the same rules and standards for scientific practice. That commitment and the apparent consensus it produces are both the genesis and the continuation of a research tradition. Paradigms involve different assumptions of truth or reality normal science is based on a modern view of reality.

46 46 Methodology The conduct of scientific inquiry Methodology is the science of finding out knowledge (truth). The standards for determining truth is rigorin logic and methods The scientific community determines the standards of rigor and professional competence. Each scientist is accountable to the sci ientific community for adhering to standards of professional competencee and norms. The visible part of our scientific conduct and results is reconstructed logic The ethics of science is in the conduct of the scientist.

47 47 Scientificc Research Scientific research is a systematic, controlled, empirical, and critical investigation of natural or social phenomena (using commonly accepted methodology) that either (a) is guided by theoryand hypotheses about the presumed (true) relations amon ng such phenomena, or b) results in theory and propositions about the possible (true) relationships among such phenomena.