Data Imputation A method used to fill in missing values due to nonresponse in surveys. The method is based on careful analysis of patterns of missing data. Types of data imputation include mean imputation, multiple imputation, hot deck and cold deck imputation. Data imputation is done to allow for statistical analysis of surveys that were only partially completed. Deduction The process of reasoning from the more general to the more specific.
Deductive Method A method of study that begins with a theory and the generation of a hypothesis that can be tested through the collection of data, and ultimately lead to the confirmation or lack thereof of the original theory. Degrees of Freedom The number of independent units of information in a sample used in the estimation of a parameter or calculation of a statistic.
The degrees of freedom limits the number variables that can be included in a statistical model. Models with similar explanatory power, but more degrees of freedom are generally prefered because they offer a simpler explanation. Dependent Variable The outcome variable. In experimental research, this variable is expected to depend on a predictor or independent variable. Descriptive Statistics Basic statistics used to describe and summarize data. Descriptive statistics generally include measures of the average values of variables mean, median, and mode and measures of the dispersion of variables variance, standard deviation, or range.
Dichotomous Variables Variables that have only two categories, such as gender male and female. Direct Effect The effect of one variable on another variable, without any intervening variables.
Direct Observation A method of gathering data primarily through close visual inspection of a natural setting. Direct observation does not involve actively engaging members of a setting in conversations or interviews.
Rather, the direct observer strives to be unobtrusive and detached from the setting. Discrete Variables A variable that can assume only a finite number of values; it consists of separate, indivisible categories.
The opposite of discrete is continuous. For example, one's gender is either "male" or "female", thus gender is discrete. A person's height could be 5 feet 1 inch, 5 feet 1. Discrimant Analysis A grouping method that identifies characteristics that distinguish between groups. For example, a researcher could use discriminant analysis to determine which characteristics identify families that seek child care subsidies and which identify families that do not.
Dispersion The spread of a variable's values. Techniques that describe dispersion include range, variance, standard deviation, and skew. Distribution The frequency with which values of a variable occur in a sample or a population. To graph a distribution, first the values of the variables are listed across the bottom of the graph. The number of times the value occurs are listed up the side of the graph. A bar is drawn that corresponds to how many times each value occurred in the data.
For example, a graph of the distribution of women's heights from a random sample of the population would be shaped like a bell. Most women's height are around 5'4" This value would occur most frequently, so it would have the highest bar.
Heights that are close to 5'4", such as 5'3" and 5'5" would have slightly shorter bars. More extreme heights, such as 4'7" and 6'1" would have very short bars. Double Barreled Question A survey question whereby two separate ideas are erroneously presented together in one question. Double Blind Experiment A research design where both the experimenter and the subjects are unaware of which is the treatment group and which is the control.
Dummy Coding A coding strategy where each value of a categorical variable is turned into its own dichotomous variable. The dichotomous variable is coded as either 0 or 1. Dummy coding is used in regression analysis to measure the effect of a categorical variable on the outcome when the categorical variable has more than 2 values.
Dummy Variables Categorical variables that are assigned a value of 0 or 1 for use in a statistical analyses see Dummy Coding. Duration Models A group of statistical models used to measure the length of a status or process.
Ecological Fallacy False conclusions made by assuming that one can infer something about an individual from data collected about groups. Econometrics A field of economics that applies mathematical statistics and the tools of statistical inference to the empirical measurement of relationships postulated by economic theory. Effect Size A measure of the strength of the effect of the predictor or independent variable on the outcome or dependent variable.
Endogeneity A threat to the assumption that the independent exogenous variable actually causes the dependent or endogenous variable. Endogeneity occurs when the dependent variable may actually be a cause of the independent variable. Sometimes this is referred to as reverse causality. For example, a researcher may note that states with the death penalty also have high murder rates.
The researcher may conclude that the death penalty causes an increase in the murder rate; however, it could be that states that experience a high murder rate are more likely to institute the death penalty. Endogeneity is the opposite of exogeneity.
Epistemology A way of understanding and explaining how we know what we know. Each research methodology is underpinned by an epistemology that serves as a guiding philosophy and provides a concrete process of research steps. Error The difference between the actual observed data value and the predicted or estimated data value.
Predicted or estimated data values are calculated in statistical analyses, such as regression analysis. Error Term The part of a statistical equation that indicates what remains unexplained by the independent variables. The residuals in regression models. Estimated Sampling Error The predictable and built-in level of error that accompanies all samples of a given size. Estimation The process by which data from a sample are used to indicate the value of an unknown quantity in a population.
Ethnographic Decision Models A qualitative method for examining behavior under specific circumstances. Ethnographic Interviewing A research method in which face-to-face interviews with respondents are conducted using open-ended questions to explore topics in great depth. Questions are often customized for each interview, and topics are generally probed extensively with follow-up questions.
Ethnographers seek to learn the language, thoughts, and practices of a society by participating in the rituals and observing the everyday routines of the community.
Ethnography is primarily based upon participant observation, direct observation, and in-depth interviewing. Evaluation Research The use of scientific research methods to plan intervention programs, to monitor the implementation of new programs and the operation of existing programs, and to determine how effectively programs or clinical practices achieve their goals.
Exogeneity The condition of being external to the process under study. For example, a researcher may study the effect of parental characteristics on their children's behaviors. A parent's religious upbringing is exogenous to their children's behaviors because it is impossible for children's current behavior to impact parent's upbringing, which occurred prior to the birth of the child.
The opposite of exogeneity is endogeneity. Experimental Control Processes used to hold the conditions uniform or constant under which an investigation is carried out.
Experimental Design A research design used to establish cause-and-effect relationships between the independent and dependent variables by means of manipulation of variables, control and randomization. A true experiment involves the random allocation of participants to experimental and control groups, manipulation of the independent variable, and the introduction of a control group for comparison purposes. Participants are assessed after the manipulation of the independent variable in order to assess its effect on the dependent variable the outcome.
Experimental Group In experimental research, the group of subjects who receive the experimental treatment or intervention under investigation. Explanatory Analysis A method of inquiry that focuses on the formulating and testing of hypotheses. Exploratory Study A study that aims to identify relationships between variables when there are no predetermined expectations as to the nature of those relations.
Many variables are often taken into account and compared, using a variety of techniques in the search for patterns. External Validity The degree to which the results of a study can be generalized beyond the study sample to a larger population.
Extraneous Variable A variable that interferes with the relationship between the independent and dependent variables and which therefore needs to be controlled for in some way. Extrapolation Predicting the value of unknown data points by projecting beyond the range of known data points. Face Validity The extent to which a survey or a test appears to actually measure what the researcher claims it measures.
To have face validity, other researchers who read the survey questions must also agree that the questions do appear to measure gender role attitudes. Factor Analysis An exploratory form of multivariate analysis that takes a large number of variables or objects and aims to identify a small number of factors that explain the interrelations among the variables or objects.
Field Notes A text document that detail behaviors, conversations, or setting characteristics as recorded by a qualitative researcher. Field notes are the principle form of data gathered from direct observation and participant observation. Field Research Research conducted where research subjects live or where the activities of interest take place. Field Work Observing human behavior or interviewing individuals within their own communities.
Field work is generally used in collecting qualitative data. It generally involves the researchers long-term relocation to the community under study. Data collection generally takes place over an extended period of time.
Fixed Effects Regression Regression techniques that can be used to eliminate biases associated with the omission of unmeasured characteristics. Biases are eliminated by including an individual-specific intercept term for all cases.
Floor The lowest limit of performance that can be assessed or measured by an instrument or process. Individuals who perform near to or below this lower limit are said to have reached the floor, and the assessment may not be providing a valid estimate of their performance levels. Focus Group An interview conducted with a small group of people, all at one time, to explore ideas on a particular topic.
The goal of a focus group is to uncover additional information through participants' exchange of ideas. Forecasting The prediction of the size of a future quantity e. Frequency Distribution The frequency with which values of a variable occur in a sample or a population.
GIS Geographical Information Systems A computer system that enables one to assemble, store, manipulate, and display geographically referenced information. Generalizability The extent to which conclusions from analysis of data from a sample can be applied to the population as a whole.
Gini Coefficient A measure of inequality or dispersion in a group of values e. The larger the coefficient the greater the dispersion. Grounded Theory The development of social science theory from the inductive analysis of data. This approach is generally used in qualitative research. The specific and detailed observations in the data are studied and understood to such an extent that a theory of more general patterns of behavior can be generated.
Heterogeneity The degree of dissimilarity among cases with respect to a particular characteristic. Heteroskedastic A distribution characterized by a changing non-constant variance or standard deviation. Heteroskedasticity is problematic in statistical models because estimated standard errors will be inefficient and biased.
Consequently, traditional significance test will not be valid. HLM enables a researcher to estimate effects within individual units, formulate hypotheses about cross level effects and partition the variance and covariance components among levels.
Histogram A visual presentation of data that shows the frequencies with which each value of a variable occurs. Each value of a variable typically is displayed along the bottom of a histogram, and a bar is drawn for each value. The height of the bar corresponds to the frequency with which that value occurs. Hypothesis A statement that predicts the relationship between the independent causal and dependent outcome variables.
Hypothesis Testing Statistical tests to determine whether a hypothesis is accepted or rejected. In hypothesis testing, two hypotheses are used: The alternative hypothesis is the hypothesis of interest; it generally states that there is a relationship between two variables. The null hypothesis states the opposite, that there is no relationship between two variables. Imputed Response A missing survey response that is filled in by the data analyst. The method to fill in the missing response is based on careful analysis of patterns of missing data.
Imputation is done to allow for statistical analysis of surveys that were only partially completed. In-depth Interviewing A research method in which face-to-face interviews with respondents are conducted using open-ended questions to explore topics in great depth. Independence The lack of a relationship between two or more variables.
For example, annual snow fall and the Yankee's season record are independent, but annual snow fall and coat sales are not independent. Independent Variable The variables that the researcher expects to be the cause of an outcome of interest. For example, if a researcher wants to examine the effect of gender on income, gender is the independent variable.
Sometimes this variable is referred to as the treatment variable or the causal variable. Index A type of composite measure that summarizes several specific observations and represents a more general dimension. Index Variable A variable that is a summed composite of other variables that are assumed to reflect the same underlying construct. Indicator An observation assumed to be evidence of the attributes or properties of some phenomenon. Indicators allow assessment of progress toward the achievement of intended outputs, outcomes, goals, and objectives.
Indicator Variable A variable that has two values, which are typically coded 0 and 1. Also referred to as a dummy variable. Indirect Effect A condition where one variable affects another indirectly through an intervening variable. For example, gender may have an indirect effect on income if gender affects wage rates.
Inductive Method A method of study that begins with specific observations and measures, from which patterns and regularities are detected. These patterns lead to the formulation of tentative hypotheses, and ultimately to the construction of general conclusions or theories. Instrument Error A type of non-sampling error caused by the survey instrument or questionnaire itself, such as unclear wording, asking respondents for information they are unable to supply or the instrument being changed in some way during the course of the research.
Interaction Effect A situation where the effect of the independent variable on the dependent variable varies depending on the value of another, additional variable. For example, teaching style and student's gender would have an interactive effect if boys learned more in a lecture style classroom, while girls learned more in a discussion style classroom. In other words, the effect of teaching style on learning varies depending on student's gender.
Intercept The expected value of a dependent variable when all the independent variables are equal to zero. Internal Validity The extent to which researchers provide compelling evidence that the causal independent variable causes changes in the outcome dependent variable.
To do this, researchers must rule other potential explanations for the changes in the outcome variable. Interval Scale A scale of measurement where the distance between any two adjacent units of measurement is the same but the zero point is arbitrary. Scores on an interval scale can be added and subtracted but cannot be meaningfully multiplied or divided. Interval Variable A variable wherein the distance between units is the same but the zero point is arbitrary. Interviewer Error A type of non-sampling error caused by mistakes made by the interviewer.
These may include influencing the respondent in some way, asking questions in the wrong order, or using slightly different phrasing or tone of voice than other interviewers. It can include intentional errors such as cheating and fraudulent data entry. The name is derived from the method that each observation is removed i. Kurtosis A statistical equation that measures how peaked a distribution is. The kurtosis of a normal distribution is 0. If kurtosis is different than 0, then the distribution is either flatter or more peaked than normal.
Least Squares A commonly used method for calculating a regression equation. This method minimizes the difference between the observed data points and the data points that are estimated by the regression equation.
Level of Significance See significance level. Likert Scale A scale that on which survey respondents can indicate their level of agreement or disagreement with a series of statements.
The responses are often scaled and summed to give a composite measure of attitudes about a topic. Linear Regression A statistical technique used to find a linear relationship between one or more multiple continuous or categorical predictor or independent variables and a continuous outcome or dependent variable.
Literature Review A comprehensive survey of the research literature on a topic. Generally the literature review is presented at the beginning of a research paper and explains how the researcher arrived at his or her research questions. Logistic Regression A special form of regression used to analyze the relationship between predictor variables and a dichotomous outcome variable.
A dichotomous variable is a variable with only two possible values, e. Logit Model A special form of regression used to analyze the relationship between predictor variables and a categorical outcome variable. Main Effect The effect of a predictor or independent variable on an outcome or dependent variable. Matched Samples Two samples in which the members are paired or matched explicitly by the researcher on specific attributes, such as IQ or income.
Also refers to samples in which the same attribute or variable is measured twice on each subject under different circumstances; also referred to as repeated measures. Maxima The maxima are points where the value of a function is greater than other surrounding points. Mean A descriptive statistic used as a measure of central tendency. To calculate the mean, all the values of a variable are added and then the sum is divided by the number of values.
Some factors that contribute to measurement error include the environment in which a survey or test is administered e. There are many more such factors that can contribute to measurement error. Measures of Association Statistics that measure the strength and nature of the relationship between variables. For example, correlation is a measure of association. Median A descriptive statistic used to measure central tendency.
The median is the value that is the middle value of a set of values. For example, if a sample of individuals are ages 21, 34, 46, 55, and 76 the median age is Member Checking During open-ended interviews, the practice of a researcher restating, summarizing, or paraphrasing the information received from a respondent to ensure that what was heard or written down is in fact correct.
Meta-Analysis A statistical technique that combines and analyzes data across multiple studies on a topic. Methodology The principles, procedures, and strategies of research used in a study for gathering information, analyzing data, and drawing conclusions. There are broad categories of methodology such as qualitative methods or quantitative methods; and there are particular types of methodologies such as survey research, case study, and participant observation, among many others.
Census Bureau to designate an area of adjacent counties except in New England where they are defined by adjacent cities. Metropolitan Statistical Areas MSAs are often used to geographically understand labor markets because individuals often look for work outside of the city or county in which they live. Minima The minima are points where the value of a function is less than other surrounding points.
To ignore the missing data and restrict analyses to those records with reported values for the variables in the analysis, implicitly invokes the assumption that the missing cases are a random subsample of the full sample, that is, they are missing completely at random MCAR.
This is a strong assumption. Missing Data Values in a data set values that were not recorded. Missing values can have many causes including a respondent's refusal to answer survey questions, an interviewer incorrectly coding a response, or questions that do not apply to a respondent. The more missing data there are in a data set, the greater the likelihood of bias. There are several coding strategies that can "fill in" missing data for statistical analyses.
These strategies are called imputation see Data Imputation. Missing Data Imputation A method used to fill in missing values due to nonresponse in surveys. Misspecification Misspecification occurs when the predictor independent variables in a statistical model are incorrect.
The most common cause of model misspecification is that important predictor independent variables are left out of the model. Misspecification often leads to incorrect estimates of the effects of the predictor independent variables that are included in the model on the outcome dependent variable. Mode A descriptive statistic that is a measure of central tendency.
It is the value that occurs most frequently in the data. For example, if survey respondents are ages 21, 33, 33, 45, and 76, the modal age is Multicollinearity A situation in which two or more predictor independent variables in a sample are highly related to each other. When using regression analysis, this can lead to incorrect estimates of their individual effects on the outcome dependent variable. Multicollinearity violates an underlying assumption of regression that each predictor independent variable has an independent impact on the outcome dependent variable.
Multilevel Modeling A model involving variables measured at more than one level of a hierarchy. The term "research methods" typically refers to the strategy or plan that a researcher has devised in order to gather data. While "research methodology" sounds similar to "research method," research methodology refers to the body of practices that govern the acquisition of knowledge within a given field. It is like an action plan full of short- and long-term goals.
It is also a set of actions—an action plan. Research methodology deals with a range of ways to make the most out of solving key research problems.
It is a composite of philosophies, ideals, It is a composite of philosophies, ideals, and foundations that drive the actions, the methods, that will be used.
Think of the methodology as the systematic way in which those tools will be employed. There is no use having a tool without having a process to use it most effectively. This is the same basic gist with method the tool and methodology the process, the guiding force. Think also of the method as a series of techniques, while the methodology is the strategy that determines the use of the techniques. The methods enable the methodology, and the methodology helps decide the best methods. To clarify further, consider this: A questionnaire is a method of data collection; it is a tool.
Qualitative research methodology is the systematic processes and ways to obtain data with a variety of qualitative research tools.
Koro-Ljungberg encourages new and experienced researchers to question common assumptions about the design and interpretation of qualitative research in this guide to qualitative research methodology. Single subject research methodology in behavioral sciences.
Research methodology is a field that is rapidly growing in importance. 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 purpose of the present investigation was to examine the role of self-perception in predicting performance of cooperative learning groups in graduate-level research methodology courses. Effect of self-perception on performance of graduate-level cooperative groups in research methodology courses.
Taking the "Q" out of research: Teaching research methodology courses without the divide between quantitative and qualitative paradigms.
Research is completed through various methods but, since the researcher is immersed within the group for an extended period of time, more detailed information is usually collected during the research.
Glossary of Key Terms This glossary provides definitions of many of the terms used in the guides to conducting qualitative and quantitative research. The definitions were developed by members of the research methods seminar (E) taught by Mike Palmquist in the s and s.
Definition of research methodology: The process used to collect information and data for the purpose of making business decisions. The methodology may include publication research, interviews, surveys and other research techniques, and. The methodology is the general research strategy that outlines the way in which research is to be undertaken and, among other things, identifies the methods to be used in it. These methods, described in the methodology, .
Material and Methods: Following the action research methodology, community participation was emphasized and teachers, parents and other stake holders participated in meetings and through consultative process each step of trauma assessment and management was finalized. Video: Research Methodology: Approaches & Techniques A research method is a systematic plan for doing research. In this lesson, we'll look at the definition for a research method and examine the.