Statistical Testing Error
In science and in life, we are always dealing with a large amount of uncertainty. That’s just how it goes. If we waited to be certain in all situations before speaking or acting, we’d never say or do anything. When we do our probabilistic testing of hypotheses, we can expect to make errors periodically. There are two types of errors that we make, and from which we hope to learn.
- TYPE I, OR ALPHA ERROR
We reject the null hypothesis when it is in reality true. (We accuse our friend of using a loaded coin when our friend was really playing fair.)
The alpha level not only sets the cutoff point at which we will reject the null hypothesis; it also sets the likelihood of committing this type of error. When we set an alpha level of .05, we are committing ourselves to a 5% chance of rejecting a true null hypothesis, at a p-level of .01 it’s 1%, at .001, it’s .1%. The lower the alpha level, the less chance of committing this type of error. But this certainty has a cost. The lower we set the alpha level, the greater the chance that we will commit a beta error and accept a false null hypothesis. We sacrifice what we call POWER in order to use a very low alpha level. This other competing type of error, which we must try to balance out the chance of, is - TYPE II, OR BETA ERROR
We fail to reject the null hypothesis when it is in reality false. (We assume our friend is playing fair when in fact he or she is playing with a loaded coin.)
Beta is the probability of making this type of error. The implication of this type of error is that in our quest to be scrupulous about not accepting a chance or random effect as an actual systematic effect of interest, we ignore a possible effect of interest.
Why all this testing?
We need our test and our significance levels to allow us a sufficient level of power as well as carefully guard against finding effects that aren’t there. Power is the potential for our research and tests to reject an actually false null hypothesis. If we set our alpha levels so low that we have little or no chance of doing so, it’s not a good thing.
Think of alpha and beta as lying on a graph with a diagonal – as one goes up, the other goes down. The .05 significance level, in most cases, is regarded as the best compromise level between alpha and beta errors, although significance of results at .01 level is generally more highly prized in the world of research. Although this is usually a very good thing, let’s say your research results show that the effect you were looking at would have occurred only 2% of the time by chance. At a an alpha level of .01, you still fail to reject the null hypothesis even though there has been an effect from your treatment. You probably did not allow yourself sufficient power in setting the alpha level. You commit a beta error.
The alpha level, along with the number of subjects, is used in conjunction with statistical tables in order to set a "critical" value for our statistic ("t" for t tests and "F" for ANOVA.) If our testing procedure yields a t or F value higher than the critical value, we can reject the null. If our obtained t or F (obtained from the test) does not exceed the critical, we FAIL TO REJECT the null (by custom we do not "Accept" because nothing has been proven and a future research study may not replicate our non-significant results. Because of the reciprocal nature of these types of error, we need to carefully consider the consequences of each before we set our alpha level.
Related Research Paper Topic Suggestions
Action Research - Action research is a form of self-reflective research paper. Custom written action research papers from Paper Masters for Undergraduate or Graduate level students.
Biases Research - Biases in Research essays discuss why it is important for researchers to acknowledge their biases when conducting research.
Collaborative Research - Paper Masters specializes in collaborative research and theory driven research papers. Paper Masters can help with your collaborative research project or find you refrences that are examples of collaborative research in any field of study.
Data Analysis - Data analysis within research discusses the process used for inspecting and modeling data in order to discover useful information.
Data Warehouse - Research papers on data warehouse discuss the repository of data from a host of sources, that deals with the business at hand.
Empirical Analytical Inquiry - Custom written research papers based upon empirical-analytical research studies from Paper Masters.
Empirical Article - Empirical Article research papers examine a type of writing for articles that relies on scientific data derived from observation and/or experimentation.
Evaluation Research - Evaluation research from Paper Masters provides custom written applied research that is based on systematically evaluating a program, action or policy.
Experimental Method - Experimental Method is a type of research methodology that uses either quasi-experimental or true experimental methodology to conduct a study.
Hermeneutic Research - Custom written undergraduate or graduate level hermeneutics research papers that focus on the interpretation of texts, events and recorded interactions.
Historical Comparative Research - Custom written historical comparitive research projects from Paper Masters - Specialists in all forms of research studies at the graduate and undergraduate level.
How To Write a Literature Review - How to write a literature review - according to Paper Masters, the experts in custom research papers and lit reviews.
Inferential Statistical Procedures - Analysis of inferential statistical procedures in academic research papers and studies. Capstone projects, Theses and doctoral projects often include inferential statistical procedures.
Literature Review Approach - How to approach writing a literature review using top-down and bottom-up research strategies.
Measurement Construction - Measurement Construction Research Papers look at a sample of an order placed on a data collection instrument with specific variables to measure.
Phenomenology - Custom written phenomenology research papers that describe a type of research known as phenomena. How or why something occurs is important in academic studies.
Qualitative Dissertation - Paper Masters shows you how to write a Qualitative Dissertation. Our writers know how to write graduate and Masters Level research and can provide you with a perfect example of how to write qualitative research for academic credit.
Qualitative Research Methods - Qualitative Research Methods research papers on the research employed in academic disciplines that seek to understand an aspect of human behavior.
Qualitative Research Report - How to analyze qualitive research reports. Tips to defining the problem statement, study purpose, research methods and data collection in a qualitative study.
Qualitative Studies - Qualitative studies such as grounded theory, phenomenology, ethnography, ethnomethodology and descriptive studies are outlined.
Quantitative Research - Quantitative Research examines types of data and statistical research and use quantitative methodology to present the results of a study.
Quantitative Research Design - Quantitative Research Design term papers look at an order on a graduate level project on quantitative statistical analysis.
Regression - Regression predicts future outcomes on past performance. Many types of academic research papers use regression analysis to illustrate data that was collected in a study. Paper Masters provides custom regression analysis in any research project.
Secondary Data Collection - Secondary Data Collection and search strategies can be divided into three criteria: data retrieval methods, data location, and Internet searching.
Statistical Hypothesis Testing - Statistical hypothesis testing in academic research papers and master's theses.
Survey Case Study Research Method - A combination of the survey research method and the case study research method is used to collect data. Sociology term papers are available at Paper Masters.
Theoretical Inquiry Research - Theoretical Inquiry in research papers from Paper Masters match your exact needs because they are custom written by professional writers.
Theoretical Orientation Hypothetical Case - This project consists of a detailed written case summary, formulation, and treatment plan based on theoretical orientation for a hypothetical patient.
What is Correlation - Correlation in an academic study is examined in light of statistical analysis.