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SUM 4011 A. Introduction to research design and different research tools. I am a senior researcher at SUM with a doctoral degree in biology. The theses was based on an interdisciplinary study in the rainforest of Guatemala.
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SUM 4011 A Introduction to research design and different research tools • I am a senior researcher at SUM with a doctoral degree in biology. The theses was based on an interdisciplinary study in the rainforest of Guatemala. • Now working on two EU projects; “Integrated water research management” “LUPIS, ex-ante assessment of land use policies in developing countries” 1
Research tools and methods. • Prescribed texts • Read and comprehend the object of each paper • Pay attention to different methodologies, form and structure. • Read them critically. • Don’t pay attention to the statistically analysis. 2
- Different types of research: experimental studies / observational studies / surveys / theoretical studies • Interdisciplinary study, social versus natural science • Important aspects of sampling design • Data analysis • Read critically a presented text Introduction to different research methods 3
Disciplinary / Interdisciplinary studies • Research often inflicts on, or poses assertion involving other disciplines. • Be aware of the competence of authors (and your own). • Is it possible for one person to be competent in more than one discipline? 7
Disciplinary / interdisciplinary study Social and /or naturalscience? Cooperation or not?? • Positive and negative aspects with interdisciplinary studies. • Typical aspects of natural-, versus social science studies?
STRIVER, an EU project with an interdisciplinary focus. • An internationalresearchprojectonintegrated resource water management (IWRM) • Four case studies in four river basins, Glomma, Tagus, Sesan and Tungabhadra. • Stakeholders gave an important input by identifying water pollution pressures and prioritizing them based on their perception and local knowledge.
Different types of studies are characterised by aspects and some studies require a particular study design • Experimental studies • Observational studies • Surveys • Theoretical studies 10
The statement of the problem serves as a guideline throughout the design of the project. • The objective follows the statement of the problem • And the methodology must serve the objectives of the study The statement of the problem, the purpose of the study 4
Hypothesis or research questions? • A hypothesis sharpen and simplify. For a hypothesis to be tested, certain statistical assumptions needs to be met. • Ex. Peres et al., and Moe et al.: What are the hypotheses ? • Research questions enables a broader explorative focus of the investigation, best used in initial phases. • Ex. Stige et al., and Nesheim et al. What are the research questions? 9
Time allocated in a study How to characterize the length of the field period in these articles? • Nesheim et al., (9 months + social anthropology research • Stige et al., several researchers, time period from 1961-2003; 1982-2003 • Peres et al., (22 tree populations), 14 researchers, several ecological factors recorded • Tuomisto et al. 43.38 km long transect, but only 2m wide, 8.6 HA (4 researchers) • DISCUSS time and effort.. 6.2
Experimental studies • Experimental studies are those which include manipulation of predictor variable and randomization of treatments. • Experiments are the best tools for establishing causal relationships empirically. • Highly controlled studies, such as laboratory experiments, may not give rise to realistic results. • There is usually a trade-off between control and realism. 11
Predictor variable : different weather conditions Experiment: random allocation of manipulated predictor variable on response variable/ study units Response variable / study units: roses
Experimental studies • An example : Estimating pine seedling response to ozone and acidic rain. • Ozone level (treatment) was forced into the chambers surrounding the plants. Different levels assigned at random. Four replicates of each level. • Acidic rain levels were imposed by dispensing volumes of premixed solutions (natural rain was excluded). Different levels assigned at random. Four replicates of each level. • Each chamber can receive only one level of the ozone-acidic rain combination. • Thus the experiment involved both manipulation of predictor variable and randomization of treatments!! 12
Observational studies • Observational studies are controlled studies designed with respect to a particular hypothesis, but which lack randomisation of treatments , i.e. there are treatments but these are not randomized. • Such studies usually involve exploring relationships between a predestined set of response and predictor variables in a natural setting. • Such studies are weaker in control than experimental studies, but are usually stronger in realism and representation. • Observational studies (and surveys) often precede experimental studies. 13
Observational studies • Which of the articles would represent an observational study, and why? • Why is this not an experimental study? • If by any means and experimental study would be possible how would that increase the reliability of results? 14
The Peres et al. article, an observational study • It tries to test a hypothesis • The response variable is subject to different treatment levels; • the tree populations (the response variable); • levels of seed exploitation(treatment levels) : persistently harvested stands, unharvested, lightly harvested stands, and moderately harvested stands
Observational studies • An example: Migration in endangered butterfly. • Measured local population size of the butterfly in 50 discrete habitat patches within an area of 15 km2, and habitat quality, vegetation height, and an index of isolation of habitat (patch). • Aim at predicting the local population density of butterfly, and relate densities to the habitat characteristics (treatments). • Thus, there are treatments, but there are no randomization of treatments! 15
Surveys • Descriptive enumerative studies that are not based on any particular hypotheses are termed surveys. • The central design issue in surveys is sampling. • When designing a study, decisions have to be made regarding allocation of effort, the size of each sample, number of replicates and which values the predictor variable should take. 17
TheNesheim et al. study - a survey • No particular hypothesis, but research questions • A field study, and the central design is sampling • The sample: the plot and subplots, and the informants • Response variables: species, people • Predictor variables: abiotic varibles such as light, moisture, soil type etc.
Theoretical studies • Theoretical studies, seeking a variety of relevant data sources • documentary studies, • preparing instruments and tools for data collection and analysis, • theoretical re-interpretation • The Ortner article in the compendium, could serve as an examples of a theoretical study. • What about the articles prescribed for these these lectures? 16
Some important concepts One, when selecting sample units, and two, randomization in manipulative experiments. With randomization we avoid potential biases in empirical studies, any statistical dependencies between sampling units Randomization – what and why?(it concerns two aspects) Replication - what and why? You replicate to increase reliability Bias what ? It is a statistical dependency between sampling units, - in other words, the selected distribution of study units are dependent, thus the results may be wrong ie. will not likely reflect the whole study population. 18
Design an interdisciplinary research project • You need to introduce the project, include a statement of the problem • Study design: • Research questions /hypothesis ?, Which disciplines • Who / what will be studied • How will the informants / study units be selected? • Numbers? Where ? • What relationship will be examined – how will you do it (what will be surveyed, measured, interviewed which tools ?) • Remember the time frame, is the project possible 19
Examples of possible subjects for analysis: • Desertification in the Sahel belt • The development of a national park in a biodiversity hot spot area • Pollution in a small community causing health problems • Agriculture and pesticides and herbicides • Knowledge of nature by a community • Energy consumption 20