Internal validity is threatened whenever there exists the possibility that alternative causes, other than the independent variable, are responsible for the effect. There are a number of possible threats to internal validity, the seven most commonly referenced threats include history, maturation, testing, instrumentation, mortality, regression, and selection. History refers to specific events, in addition to the treatment, that occur between the first and second measurement. The longer the interval between the pretest and posttest, the more viable this threat becomes. Maturation pertains to changes in physical, intellectual, or emotional characteristics, that occur naturally over time, that influence the results of a research study. For example, in longitudinal studies, individuals grow older and become more sophisticated. Testing, refers to the effects of taking a test upon performance on a second testing. Exposure to the pretest may influence performance on a posttest. The shorter the interval between the pretest and posttest, the more viable this threat becomes. Instrumentation is concerned with changes in the way a test or other measuring instrument is calibrated that could account for results of a research study. This threat is most likely to occur from an unreliable measuring instrument (Creswell, 2009).
There are two types of research that can be conducted in research studies, these are qualitative and quantitative (Newman, 2011). Qualitative research is a process that uses detailed oriented methodology that tries to achieve a profound knowledge or understanding of specific incident and circumstance, wh...
Within scientific research there is always a strong debate between those that prefer quantitative methods and those who prefer qualitative ones. proponents of quantitative methods have built the standards in experimental research and in researches performed on a large number of subjects and which use sampling criteria and statistical analysis techniques. On the other side, the qualitative method uses procedures of qualitative nature both at the level of collecting the data as well as the level of analyzing them (Tagliapietra, Trifan, Raineri & Lis, 2009). The gathering data procedures include: interviews, group discussions, observations, journals; while the analysis procedures include coding, categorizations and systematic confrontation between the categories and their dimensions. Such research is often defined as an explorative one, opposite to “classical” scientific research aiming to confirm / disconfirm initial hypothesis. Among the qualitative methods used in the scientific research we can list: Focus Group, Speech Analysis, Conversation Analysis, Grounded Theory and Phenomenological Interpretative Analysis (Tagliapietra, Trifan, Raineri & Lis, 2009).
The most popular method of quantitative research is an experiment, which gives casual information and hard numbers (Guts, 2014). Experiments are easy to understand, and provide accessible information that helps predict human behavior (Guts, 2014). In experiments, researchers manipulate variables using experiment and control groups. (Guts, 2014). An experiment includes independent and dependent variables. An independen...
Experimental research attempts to identify relationship by conducting controlled experiments psychological experiments; furthermore, the experimental is a quantitative approach designed to discover the effects of presumed causes (Christensen, Johnson, & Turner, 2014). The key feature of this approach is that one thing is deliberately varied to see what happens to something else to determine the effects of presumed cause. Some individuals use exercise to see if they can lose weight,
The word qualitative assumes an emphasis on the qualities of object and on processes and meanings that are not experimentally examined or measured from the point of quantity, amount, depth, or periodicity. Qualitative researchers accent the socially constructed nature of actuality, the close relationship between the researcher and what is studied, and the situational imperatives that shape demands. Researchers look for answers to questions that accent how social experience is created and given meaning. In contrast, quantitative studies stress the dimension and analysis of causal relationships between variables, not processes. Qualitative forms of demand are thought-out by many social and behavioral scientists to be as much a perspective on how to approach investigating a research problem as it is a method. Denzin, Norman. K. and Yvonna S. Lincoln. Handbook of Qualitative Research. 2nd edition. Thousand Oaks, CA: Sage, 2000.
Quantitative and qualitative research use similar design but, they differ in terms of their epistemological, theoretical and methodological underpinnings. Quantitative research is objectivist epistemology and thus seeks to develop explanatory universal laws in social behaviors by statistically measuring what it assumes to be a static reality. The quantitative research leans towards the views of psychological and social phenomena. On the other hand, qualitative research does not rely on any knowledge from the independent knower, but however socially constructed and that reality is neither static nor fixed. Nonetheless, there are multiple realities that different cultural groups construct on the basis of their world views or value systems, there are multiple interpretations or perspectives on any event or situation (Yilmaz, K.
The aspect of discerning quantitative and qualitative research enables a researcher with the ability to present a phenomenon to the academic community in an appropriate manner (Venkatesh, Brown, & Bala, 2013). The researcher chooses the best method to present the study to an audience based on items such as the type of study to be conducted, the type of data needed for the study, and the amount of resources needed to complete the study. The resources include money, personnel, and arguably the most important resource of time. Additionally, the researcher becomes astute at reviewing other articles in similar methodology, which are either of a quantitative, qualitative, or a mixed method research design. In this article, the author will focus on five select qualitative articles. During this focus, the author will provide a summarization of a topic followed by presenting the problem, purpose, design, and findings of the research article. Moreover, Venkatesh, et al. (2013) stated qualitative research assists in providing the reader a better understanding of a phenomenon by articulating a narrative description of the study to the audience.
According to Burns and Bush (2006), “quantitative research is defined as research involving the use of structured questions in which the response options have been predetermined and a large number of respondents is involved” (p. 202). Quantitative research often uses numerical values; however, the data is always very structured in standardized form, are clear in definition, and provide an orderly process.
Quantitative is based on empirical research, critical interpretation of data in forms of numbers. Mostly, quantitative research uses deductive approach, which begins with a theory, generalizes and tests theory or hypothesis. Quantitative is suitable for researcher aiming at answering questions, operational definitions, an experiment of time series to see how things are changed in number, casual explanation and deductive reasoning. Quantitative research data is based on questionnaires collected from descriptive information, attitude survey, explanatory survey through an interview, form filling, portal, email. (Sue, 2017; University of Surrey, 2017)
Earlier article (University of Paisley 1997) defined approaches to research primitively using these two simplest words helped presenting a good contrast between differing schools of thought. If in a research the emphasis of data collection is on the quality rather than the quantity, it is qualitative. However, when the research is of “quantitative orientation”, data collection focuses on some form of factual relationship.
In comparison to qualitative approach, quantitative data can be generalised as it can be used across a larger scale of variables, for example using larger amount of participants. It is commonly used in the human science field of research because it is replicable making it reliable. It provides numerical, ratings and statistical findings which minimises any bias outcome. On the other hand the quantitative approach is closed to interpretation and doesn’t work well in recognising new
Qualitative and Quantitative study designs both can be beneficial in research design. They both provide valuable options for researchers in the field. These techniques can either be used separately in a research study or they can be combined to achieve maximum information. This paper will define the terms qualitative and quantitative; describe the similarities and differences between each; discuss how qualitative and/or quantitative research designs or techniques could be used in the evaluation of my proposed research; and discuss why linking analysis to study design is important.
Qualitative and quantitative researcher’s exhibited conflicting ways of approaching a research. Some researchers prefer qualitative over quantitative and vice-versa. Also, it is common for qualitative and quantitative to be used together in a research. But, both methods when carried out correctly provide good research. Plus, both methods have their own unique differences and characteristics. In this paper I will define three of these characteristics in a quantitative and qualitative research design and discuss and compare their differences. (Smith & Davis, 2010)