Inductive and Deductive Research Approaches Compare and Contrast Inductive and Deductive Research Approaches By L. Karen Soiferman University of Manitoba April 2010 1 Inductive and Deductive Research Approaches Abstract This discussion paper compares and contrasts inductive and deductive research approaches as described by Trochim (2006) and Plano Clark and Creswell (2007). It also examines the exploratory and confirmatory approaches by Onwueghuzie and Leech (2005) with respect to the assumption each holds about the nature of knowledge. The paper starts with an historical overview of the two main types of research commonly used in educational settings. It continues with a discussion of the elements that showcase the differences and similarities between the two major research approaches. The elements discussed include: intent of the research, how literature is used, how intent is focussed, how data are collected, how data are analyzed, the role of the researcher, and how data are validated. In addition, there is a section which addresses the decisions researchers must make in choosing the research methodology that allows them to answer their research question. The focus of the discussion is on how the two types of research methodology can be used effectively in an educational setting. It concludes with a look at how the different methods of research can be used collaboratively to form a more complete picture of a research study. 2 Inductive and Deductive Research Approaches Introduction Trochim (2006) refers to two “broad methods of reasoning as the inductive and deductive approaches (p.1). He defines induction as moving from the specific to the general, while deduction begins with the general and ends with the specific; arguments based on experience or observation are best expressed inductively, while arguments based on laws, rules, or other widely accepted principles are best expressed deductively. Creswell and Plano Clark (2007) say that the deductive researcher “works from the ‘top down’, from a theory to hypotheses to data to add to or contradict the theory” (p.23). In contrast, they define the inductive researcher as someone who works from the “bottom-up, using the participants’ views to build broader themes and generate a theory interconnecting the themes” (p. 23). In research, the two main types of analysis typically used are quantitative (deductive) and qualitative (inductive). Though there seems to be some disagreement among researchers as to the best method to use when conducting research and gathering data, these two methods are not mutually exclusive and often address the same question using different methods. Historical Context Onwuegbuzie and Leech (2005) suggest that “instructors of quantitative and qualitative research often view themselves as being in competition with each other” (p. 267). The authors go on to argue that “this polarization has promoted . . . ’uni-researchers’ [who are] namely researchers who restrict themselves either exclusively to quantitative or to qualitative research methods” (p. 268). The reason Onwuegbuzie and Leech give for changing the names dates back to the end of the 19th century when quantitative research was characterized by an implied 3 Inductive and Deductive Research Approaches objectivity and was considered the only way to conduct research. The beginning of the 20th century marked what they refer to as the second research methodology phase. It was at this time that the qualitative research method emerged. Researchers who followed this scientific method believed that “social reality was constructed and thus was subjective” (p. 269). It was at this point that the polarization of quantitative and qualitative research methods began. In the later part of the 20th century the post-structuralists and post-modernists believed in the “incompatibility thesis” (p.270) which said that the quantitative and qualitative paradigms could not coexist (Onwuegbuzie & Leech, 2005). The major difference between the two methods is centered on how they view the nature of reality. The quantitative theorists believe “in a single reality that can be measured reliably and validly using scientific principles”, while qualitative theorists “believe in multiple constructed realities that generate different meanings for different individuals, and whose interpretations depend on the researcher’s lens” (Onwuegbuzie & Leech, 2005, p. 270). It is the relationship between the researcher and the participant that characterizes the disciplines. In quantitative research it is believed that researchers should separate themselves from the participants while qualitative researchers are aware that the relationship between the researcher and the participant is important in the understanding of the observable event. In addition, quantitative researchers believe that “research should be value-free,” while the qualitative researcher understands that “the research is influenced to a great extent by the values of the researcher” (Onwuegbuzie & Leech, 2005, p. 271). Despite the many differences, Onwuegbuzie and Leech (2005) contend that there are many similarities between the two orientations. They propose replacing the terms qualitative 4 Inductive and Deductive Research Approaches and quantitative with exploratory and confirmatory to more clearly reflect the relationship between the two methodologies. The methods may be different but the goals remain the same and Onwuegbuzie and Leech (2005) worry that the separation of the two paradigms can lead students in graduate school to becoming “one-dimensional with regards to their knowledge of the research process” (p. 272). They go on to say that “we continue to prepare students for an ‘either-or’ world, a dichotomous world, that no longer exists” (p.272). Onwuegbuzie and Leech (2005) suggest that “those who teach social/behavioural research methodology have to stop identifying themselves as qualitative or quantitative researchers” (p. 276). The method chosen should depend in large part on what the research question was, what one wants to know, and how they determine they will arrive at that knowledge. According to Trochim (2006), the context, purpose, and types of research questions asked will define the methodological foundations of a study. Onwuegbuzie and Leech (2005) point to the fact that both methods include the use of research questions which are addressed through some type of observation. They also note that the observations in either method will lead the researcher to question why what they observed happened. Another similarity is how the two paradigms interpret data. Both use some form of analysis to find the meaning and employ techniques to verify the data. Compare and Contrast Quantitative research often translates into the use of statistical analysis to make the connection between what is known and what can be learned through research. Collecting and analyzing data using quantitative strategies requires an understanding of the relationships among variables using either descriptive or inferential statistics. Descriptive statistics are used to draw inferences about populations and to estimate the parameters of those populations (Trochim, 5 Inductive and Deductive Research Approaches 2006). Inferential statistics are based on the descriptive statistics and the assumptions that generalize to the population from a selected sample (Trochim, 2006). With quantitative analysis, it is possible to get visual representations for the data using graphs, plots, charts, and tables. For researchers using quantitative analysis, the conclusions are drawn from logic, evidence, and argument (Trochim, 2006). The interpretation of raw data is guided by the general guidelines presented to evaluate the assertions made and to assess the validity of the instrument. Quantitative analysis also employs protocols to control for, or anticipate, as many threats to validity as is possible. Qualitative research can be defined as a study which is conducted in a natural setting. The researcher, in effect, becomes the instrument for data collection. It is up to the researcher to gather the words of the participants and to analyze them by looking for common themes, by focusing on the meaning of the participants, and describing a process using both expressive and persuasive language (Creswell, 2005). Creswell (2005) defines qualitative study as: a type of educational research in which the researcher relies on the view of participants, asks broad, general questions, collects data consisting largely of words (or texts) from participants, describes and analyzes these words for themes, and conducts the inquiry in a subjective, biased manner (p. 39). Qualitative research is a rigorous approach to finding the answers to questions. It involves spending an extensive amount of time in the field, working in the often complex, time consuming process of data analysis, writing long passages, and participating in a form of social and human science research that does not have firm guidelines or specific procedures. 6 Inductive and Deductive Research Approaches Conclusions change and evolve continuously as more data is collected. Qualitative research is often said to employ inductive thinking or induction reasoning since it moves from specific observations about individual occurrences to broader generalizations and theories. In making use of the inductive approach to research, the researcher begins with specific observations and measures, and then moves to detecting themes and patterns in the data. This allows the researcher to form an early tentative hypothesis that can be explored. The results of the exploration may later lead to general conclusions or theories (Creswell, 2005). Creswell and Plano Clark (2007) operate from the assumption that both qualitative research and quantitative research address the same elements in the research process. The differences arise due to the way that the researchers implement each step. For Creswell and Plano Clark (2007), the differences are not opposites but are rather differences on a continuum. As a result of this conclusion, they maintain that no one study is purely quantitative or qualitative and that each method has many of the same elements. The following elements will be discussed to show the differences and similarities between the two major research approaches: intent of the research, how literature is used, how intent is focussed, how data are collected, how data are analyzed, the role of the researcher, and how data are validated. Intent of the Research The intent of research is typically expressed in the form of a purpose statement or the guiding objectives of the study. In quantitative research, the intent is usually to test theories deductively searching for evidence to either support or to refute the hypothesis, while qualitative 7 Inductive and Deductive Research Approaches researchers gather information from individuals to identify themes which allow them to develop theories inductively (Creswell & Plano Clark, 2007). How Literature is Used For quantitative researchers the literature review plays a major role in justifying the research and identifying the purpose of the study. The literature can be used to identify the questions to be asked and to inform the hypotheses. Literature reviews in quantitative research are more comprehensive and more detailed than is the case in qualitative research. In qualitative research, the literature review is used to provide evidence for the purpose of the study and to identify the underlying problem that will be addressed by the inquiry. The literature review is typically brief and does not usually guide the research questions to the same extent as literature reviews in quantitative research does. This is done to ensure that the literature does not limit the types of information the researcher will learn from the participants (Creswell & Plano Clark, 2007). How Intent is Focused The intent of a study and the literature review help to narrow the hypotheses and research questions. In quantitative research, the intent focuses on pointed, close-ended questions that test specific variables that derive from the hypotheses. The researcher tests these hypotheses in an attempt to support or refute the relationship statements in the theories. In qualitative research, the intent is to learn from the participants. Therefore, the questions tend to be open-ended to permit the complexity of a single idea or phenomenon to emerge from the participants’ 8 Inductive and Deductive Research Approaches perspectives. The researcher often focuses on a single phenomenon to gather as much information as possible about that particular phenomena (Creswell & Plano Clark, 2007). How Data are Collected In quantitative research, data can be collected from many participants at many research sites. Researchers rely on gathering information either by sending or administering testing instruments to participants. Data is usually collected through the use of numbers which can be statistically analyzed. In qualitative research, the words and images of a few participants collected at their respective research sites, are recorded by the researcher (Creswell & Plano Clark, 2007). How Data are Analyzed Quantitatively Quantitative research makes use of numerical statistical analysis which allows researchers to either reject the hypotheses or to determine the effect size. Analyzing the data involves addressing each one of the research questions or hypotheses individually. Creswell (2005) identifies two types of statistical analysis: descriptive and inferential. He says that researchers need “descriptive statistics that indicate central tendencies in the data (mean, mode, median), the spread of scores (variance, standard deviation, and range), or a comparison of how one score relates to others (z-scores, percentile rank)” ( p.181). In addition, he says that analyzing the data might also identify the variables: independent, dependent, control, or mediating. The second type of statistical analysis depends on the use of inferential statistics. This type of analysis allows the researcher to compare the effect of independent variables on one or 9 Inductive and Deductive Research Approaches more groups by analyzing changes in the dependent variable (Creswell, 2005). Creswell (2005) says that this allows the researcher to analyze data from a sample and then to draw conclusions about an unknown population. The purpose of this kind of study is to assess whether the differences in groups (their means) or the relationship among variables is much greater or less than what we would expect for the total population (Creswell, 2005). How Data are Analyzed Qualitatively Qualitative researchers choose their analysis methods not only by the research questions and types of data collected but also based on the philosophical assumptions underlying the study. Analysis also requires an understanding of how to make sense of text and images so that the researcher can form answers to the research questions (Creswell, 2005). Qualitative researchers look for patterns or themes in the texts or image analysis. They also look for larger patterns of generalizations (Creswell & Plano Clark, 2007). Data are gathered through methods of observation, interviewing, and document analysis. These results cannot be measured exactly, but must be interpreted and organized into themes or categories. Creswell (2005) discusses six steps commonly used in analyzing qualitative data. The first step is to generate a large consolidated picture from the detailed data (transcriptions or typed notes from interviews) to the more specific: codes and themes. Secondly, it involves analyzing data while still in the process of collecting data. In qualitative research, the data collection and analysis are carried out at the same time. This is different from quantitative research where the collection of data comes before analysis. Thirdly, the phases of research in qualitative research are recursive, where the researcher can move back and forth between collecting data and 10