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Terms in this set (277)
Alternative Hypothesis
A specific statement of prediction that usually states what you expect will happen in your study
Anonymity
The assurance that no one, including the researchers, will be able to link data to a specific individual
Attribute
A specific value of a variable
Cause Construct
Your abstract idea or theory of what the cause is in a cause-effect relationship you are investigating
Concept Mapping
Two dimensional graphs of a group's ideas where ideas that are more similar are located closer together and those judged less similar are more distant. Concept maps are often used by a group to develop a conceptual framework for a research project
Conclusion Validity
The degree to which conclusions you reach about relationships in your data are reasonable
Confidentiality
An assurance made to study participants that identifying information about them acquired through the study will not be released to anyone outside of the study
Constructivist
People who hold a philosophical position that maintains that reality is a conceptual construction. In constructivism, the emphasis is placed on understanding how we construe the world. Constructivists may be realists or subjectivists
Correlational Relationship
Two variables that perform in a synchronized manner
Critical Realism
The belief that there is an external reality independent of a person's thinking (realism) but that we can never know that reality with perfect accuracy (critical)
Cross-Sectional
A study that takes place at a single point in time
Deductive
Top-down reasoning that works from the more general to the more specific
Dependent Variable
The variable affected by the independent variable, for example, the outcome
Ecological Fallacy
Faulty reasoning that results from making conclusions about individuals based only on analyses of group data
Effect Construct
Your abstract idea or theory of what the outcome is in a cause-effect relationship you are investigating
Empirical
Based on direct observations and measurements of reality
Epistemology
Is the philosophy of knowledge or of how you come to know
Evidence-Based Practice
The use of the best available programs or treatments based on careful evaluation using critically reviewed research
Exception Fallacy
A faulty conclusion reached as a result of basing a conclusion on exceptional or unique cases
Exhaustive
The property of a variable that occurs when you include all possible answerable responses
Hierarchical Modeling
The incorporation of multiple units of analysis at different levels of a hierarchy within a single analytic model
Hypothesis
A specific statement of prediction
Hypothetical-Deductive Model
A model in which two mutually exclusive hypotheses that together exhaust all possible outcomes are tested, such that if one hypothesis is accepted, the second must therefore be rejected
Independent Variable
The variable that you manipulate - a program or treatment is typically an independent variable
Inductive
Bottom-up reasoning that begins with specific observations and measures and ends up as general conclusion or theory
Informed Consent
A policy of informing study participants about the procedures and risks involved in research that ensures that all participants must give their consent to participate
Institutional Review Board (IRB)
A panel of people who review research proposals with respect to ethical implications and decide whether additional actions need to be taken to assure the safety and rights of participants
Longitudinal
A study that takes place over time
Methodology
The methods you use to try to understand the world better
Mixed Methods
Any research that uses multiple research methods to take advantage of the unique advantages that each method offers
Mutually Exclusive
The property of a variable that ensures that the respondent is not able to assign two attributes simultaneously
Natural Selection Theory of Knowledge
A theory that ideas have survival value and that knowledge evolves through a process of variation, selection and retention
Negative Relationship
A relationship between variables in which high values for one variable are associated with low values on another variable
Null Hypothesis
The hypothesis that describes the possible outcomes other than the alternative hypothesis
One-Tailed Hypothesis
A hypothesis that specifies a direction
Operationalization
The act of translating a construct into its manifestation. The result is also referred to as an operationalization; that is you might describe your actual program as an operationalized program
Positive Relationship
A relationship between variables in which high values for one variable are associated with high values on another variable, and low values are associated with low values
Positivism
The philosophical position that the only meaningful inferences are ones that can be verified through experience or direct measurement. Positivism is often associated with the stereotype of the hard-headed, lab-coat scientist who refuses to believe in something if it can't be seen or measured directly
Post-Positivism
The rejection of positivism in favor of a position that can make reasonable inferences about phenomena based upon theoretical reasoning combined with experience-based evidence
Qualitative Data
Data in which the variables are not in a numerical form, but are in the form of text, photographs, sound bytes, and so on
Qualitative Variable
A variable that is not in numerical form
Quantitative Data
The numerical representation of some object. A quantitative variable is any variable that is measured using numbers
Quantitative Variable
Data in the form of numbers
Relationship
Refers to the correspondence between two variables
Repeated Measures
Two or more waves of measurement over time
Requests for Proposals (RFPs)
RFPs, published by government agencies and some companies, describe some problems that the agency would like researchers to address. Typically, the RFP describes the problem that needs addressing, the contexts in which it operates, the approach the agency would like you to take to investigate the problem, and the amount the agency would be willing to pay for such research
Research Question
The central issue being addressed in the study, which is typically phrased in the language of theory
Right to Service
The ethical issue involved when participants do not receive a service that they would be eligible for if they were not in your study
Subjectivist
The belief that there is no external reality and that the world as you see it is solely a creation of your own mind
Theoretical
Pertaining to theory social research is theoretical, meaning that much of it is concerned with developing, exploring, or testing the theories or ideas that social researchers have about how the world operates
Third-Variable Problem
An unobserved variable that accounts for a correlation between two variables
Threats to Validity
Reasons your conclusion or inference might be wrong
Time Series
Many waves of measurement over time
Two-Tailed Hypothesis
A hypothesis that does not specify a direction
Unit of Analysis
The entity that you are analyzing in your analysis
Validity
The best available approximation of the truth of a given proposition, inference or conclusion
Variable
Any entity that can take on different values
Voluntary Participation
For ethical reasons, researchers must ensure that study participants are taking part in a study voluntarily and are not coerced
Bell Curve
Smoothed histogram or bar graph describing the expected frequency for each value of a variable. The name comes from the fact that such a distribution often has the shape of a bell
Cluster or Area Random Sampling
A sampling method that involves dividing the population into groups called clusters, randomly selecting clusters, and then sampling each element in the selected clusters. This method is useful when sampling a population that is spread across a wide geographic area
Expert Sampling
A sample of people with known or demonstrable experience and expertise in some area
External Validity
The degree to which the conclusions in your study would hold for other persons in other places and at other times
Generalizability
The degree to which study conclusions are valid for members of the population not included in the study sample
Gradient of Similarity
The dimension along which your study context can be related to other potential contexts to which you might with to generalize. Contexts that are closer to yours along the gradient of similarity of place, time, people, and so on can be generalized to with more confidence than ones that are further away
Heterogenity Sampling
Sampling for diversity or variety
Modal Instance Sampling
Sampling for the most typical case
Multistage Sampling
The combining of several sampling techniques to create a more efficient or effective sample than the use of any one sampling type can achieve on its own
Nonprobability Sampling
Sampling that does not involve random selection
Nonprobational Quota Sampling
A sampling method in which you sample until you achieve a specific number of sampled units for each subgroup of a population, where the proportions in each group are not the same
Population
The group you want to generalize to and the group you sample from in your study
Population Parameter
The mean or average you would obtain if you were able to sample the entire population
Probability Sampling
Method of sampling that utilizes some form of random selection
Proportional Quota Sampling
A sampling method in which you sample until you achieve a specific number of sampled units for each subgroup of a population, where the proportions in each group are not the same
Proximal Similarity Model
A model for generalizing from your study to another context based upon the degree to which the other context is similar to your study context
Quota Sampling
Any sampling method in which you sample until you achieve a specific number of sampled units for each subgroup of a population
Random Selection
Process or procedure that assures that the different units in your population are selected by chance
Response
A specific measurement value that a sampling unit supplies
Sampling/Sample
The actual units you select to participate in your study
Sampling Distribution
The theoretical distribution of an infinite number of samples of the population of interest in your study
Sampling Error
The error in measurement associated with sampling
Sampling Frame
The list from which you draw your sample. In some cases, there is no list; you draw your sample based upon an explicit rule
Sampling Model
A model for generalizing in which you identify your population, draw a fair sample, conduct your research, and finally, generalize your results to other population groups
Simple Random Sampling
A method of sampling that involves drawing a sample from a population so that every possible sample has an equal probability of being selected
Snowball Sampling
A sampling method in which you sample participants based upon referral from prior participants
Standard Deviation
The spread of variability of the scores around their average in a single sample. The standard deviation, often abbreviated SD, is mathematically the square root of the variance. The SD and variance both measure dispersion, but because the SD is measured in the same units as the original measure and variance is measured in squared units, the SD is usually more directly interpretable and meaningful
Standard Error
The spread of the averages around the average of averages in a sampling distribution
Statistic
A specific value that is estimated from data
Stratified Random Sampling
A method of sampling that involves dividing your population into homogenous subgroups and then taking a simple random sample
Systematic Random Sampling
A sampling method in which you determine randomly where you want to start selecting in the sampling frame and then follow a rule to select every xth element the sampling frame list (where the ordering of the list is assumed to be random)
Concurrent Validity
An operationalizations ability to distinguish between groups that it should theoretically be able to distinguish between
Construct Validity
The degree to which inferences can legitimately be made from the operationalizations in your study to the theoretical constructs on which those operationalizations are based
Content Validity
A check of the operationalization against the relevant content domain for the construct
Convergent Validity
The degree to which the operationalization is similar to (converges on) other operationalizations to which it should be theoretically similar
Criterion-Related Validity
The validation of a measure based on its relationship to another independent measure as predicted by your theory of how the measures should behave
Cronbach's Alpha
One specific method of estimating the reliability of a measure. Although not calculated in this manner, Cronbach's alpha can be thought of as analogous to the average of all possible split-half correlations
Discriminant Validity
The degree to which concepts that should not be related theoretically are, in fact, not interrelated in reality
Face Validity
A type of validity that assures that "on its face" the operationalization seems like a good translation of the construct
Mono-Method Bias
A threat to construct validity that occurs because you use only a single method of measurement
Mono-Operation Bias
A threat to construct validity that occurs when you rely on only a single implementation of your independent variable, cause, program, or treatment in your study
Pattern Matching
The degree of correspondence between two patterns
Predictive Validity
A type of construct validity based on the idea that your measure is able to predict what it theoretically should be able to predict
Reliability
The degree to which a measure is consistent or dependable; the degree to which it would give you the same result over and over again, assuming the underlying phenomenon is not changing
Translation Validity
A type of construct validity related to how well you translated the idea of your measure into its operationalization
True-Score Theory
A theory that maintains that every measurement is an additive composite of two components: the true ability of the respondent and random error
Dichotomous Question/ Dichotomous Response Scale/ Dichotomous Response Format
A question with two possible responses
Filter or Contingency Question
A question you ask the respondents to determine whether they are qualified or experieces enough to answer a subsequent one
Focus Group
A qualitative measurement method where input on one or more focus topics is collected from participants in a small-group setting where the discussion is structured and guided by a facilitator
Group-Administered Questionnaire
A survey that is administered to respondents in a group setting
Interval-Level Response Format
A response measured on an interval level, where the size of the interval between potential response values is meaningful. Most 1 to 5 rating responses can be considered interval level
Likert Response Format
An interval-level response format that uses a 5-point integer scale
Mail Survey
A paper-and-pencil survey that is sent to respondents through the mail
Multioption Variable
A question format in which th erespondent can pick multiple variables from a list
Nominal Response Format (Response Format)
A response format that has a number beside each choice where the number has no meaning except as a placeholder for that response
Ordinal Response Format
A response format in which respondents are asked to rank the possible answers in order of preference
Response Brackets
A question response type that includes groups of answers, such as between 30 and 40 years old, or between $50,000 and $100,000 annual income
Response Scale
A sequential numerical response format, such as a 1-to-5 rating format
Semantic Differential
A scaling method in which an object is assessed by the respondent on a set of bipolar adjective pairs
Single-Option Variable
A question response list from which the respondent can check only one response
Structured Response Formats
A response format that is determined prior to administration
Telephone Interview
A personal interview that is conducted over the telephone
Unstructured Response Formats
A response format that is not predetermined and where the response is determined by the respondent
Guttman Scaling
The process of developing a scale in which the items are assigned scale values that allow them to be placed in a cumulative ordering with respect to the construct being scaled
Index
A quantitative score that measures a construct of interest by applying a formula or a set of rules that combines relevant data
Likert Scaling
The process of developing a scale in which the ratings of the items are summed to get the final scale score. Ratings are usually done using a 1-to-5 disagree-to-agree response format. Likert Scales are also called summated scales.
Scaling
The branch of measurement that involves the construction of an instrument that associates qualitiative constructs with quantitative metric units
Thurstone Scaling
The process of developing a scale in which the scale items have interval-level numerical values where the final score is the average scale value of all items with which the respondent agreed
Weighted Index
A quantitative score that measures a construct of interest by applying a formula or a set of rules that combines relevant data where the data components are weighted differently
Case Study
An intensive study of a specific individual or specific context
Coding
The process of categorizing qualitative data
Content Analysis
The analysis of text documents. The analysis can be quantitative, qualtitative, or both. Typically, the major purpose of content analysis is to identify patterns in text.
Data Audit
A systematic assessment of data and data collection procedures conducted to establish and document the credibility of data collection processes and potential inaccuracies in the data
Direct Observation
The process of observing a phenomenon to gather information about it. This process is distinguished from participant observation in that a direct observer does not typicallytry to become a participant in the context and does strive to be as unobtrusive as possible so as not to bias the observation
Exception Dictionary
A dictionary that includes all nonessential words like is, and, of, in a content analysis study
Field Research
A research method in which the researcher goes into the field to observe the phenomenon in its natural state
Indirect Measure
An unobtrusive measure that occurs naturally in a research context
Participant Observation
A method of qualitative observation in which the researcher becomes a participant in the culture or context being observed
Qualititative Measures
Data not recorded in numerical form
Secondary Analysis
Analysis that makes use of already existing data sources
Unitizing
In content analysis, the process of breaking continuous text into separate units that can subsequently be coded
Unobtrusive Measures
Methods used to collect data without interfering in the lives of the respondents
Unstructured Interviewing
An interviewing method that uses no predetermined interview protocol or survey and in which the interview questions emerge and evolve as the interview proceeds
Causal
Pertaining to a cause-effect relationship
Causal Relationship
A cause-effect relationship. For example, when you evaluate whether your treatment or program causes an outcome to occur, you are examining a causal relationship
Compensatory Equalization of Treatment
A social threat to internal validity that occurs when the control group is given a program or treatment (usually by a well-meaning third party) designed to make up for or "compensate" for the treatment the program group gets
Compensatory Program
A program given to only those who need it on the bases of some screening mechanism
Compensatory Rivalry
A social threat to internal validity that occurs when one group knows the program another group is getting and, because of that, develops a competitive attitude with the other group
Control Group
A group, comparable to the program group, that did not receive the program
Covariation of the Cause and Effect
A criterion for establishing a causal relationship that holds that the cause and effect must be related or co-vary
Design
Design of a study is the specification of how the research question will be answered
Diffusion or Limitation of Treatment
A social threat to internal validity that occurs because a comparison group learns about the program either directly or indirectly from program group participants
History Threat
A threat to internal validity that occurs when some historical event affects your study outcome, hypothesis. A specific statement of prediction
Instrumentation Threat
A threat to internal validity that arises when the instruments (or observers) used on the post-test and the pretest differ
Internal Validity
The approximate truth of inferences regarding cause-effect or causal relationships
Maturation Threat
A threat to validity that is a result of natural maturation that occurs between pre-and post measurement
Mortality Threat
A threat to validity that occurs because a significant number of participants drop out
Multiple-Group Threat
An internal validity threat that occurs in studies that use multiple groups
Null Case
The case where the null hypothesis appears to be correct
Plausible Alternative Explanation
Any other cause that can bring about an effect that is different from your hypothesized or manipulated cause
Posttest-Only Nonexperimental Design
A reseach design in which only a posttest is given. It is referred to as non-experimental because no control group
Posttest-Only Randomized Experiment
An experiment in which the groups are randomly assigned and receive only a posttest
Pre-Post Nonequivalent Groups Quasi-Experiment
A research design in which groups receive both a pre- and posttest, and group assignment is not randomized, and therefore, the groups may be nonequivalent, making it a quasi-experiment
Regression Threat
A statistical phenomenon that causes a groups average performance on one measure to regress toward or appear closer to the mean of that measure than anticipated or predicted. Regression occurs whenever you have a non-random sample from a population and two measures that are imperfectly correlated. A regression threat will bias your estimate of the groups posttest performance and can lead to incorrect causal inferences
Resentful Demoralization
A social threat to internal validity that occurs when the comparison group knows what the program group is getting and becomes discouraged or angry and gives up
Selection Bias/Threat
Any factor other than the program that leads to posttest differences between groups
Selection-History Threat
A threat to internal validity that results from any other event that occurs between pretest and posttest that the groups experience differently
Selection Instrumentation
A threat to internal validity that results from differential changes in the test used for each group from pretest to posttest
Selection Maturation Threat
A threat to internal validity that arises from any differential rates of normal growth between pretest and posttest for the groups
Selection-Mortality
A threat to internal validity that arises when there is differential nonrandom dropout between pretest and posttest
Selection-Regression
A threat to internal validity that occurs when there are different rates of regression to the mean in the two groups
Selection-Testing (Threat) or Selection Instrumentation Threats
A threat to internal validity that occurs when a differential effect of taking the pretest exists between groups on the posttest
Single-Group Threats (to Internal Validity)
A threat to internal validity that occurs in a study that uses only a single program or treatment group and no comparison or control
Social Interaction Threats
Threats to internal validity that arise because social research is conducted in real-world human contexts where people react to not only what affects them, but also to what is happening to others around them
Social Threats to Internal Validity
Threats to internal validity that arise because social research is conducted in real-world human contexts where people will react to not only what affects them, but also to what is happening to others around them
Temporal Precedence
Establishing that the hypothesized cause occurs earlier in time than the effect
Testing Threat
A threat to internal validity that occurs when taking the pretest affects how participants do on the posttest
Ethnography
Study of a culture using qualitiative field research
Feasibility
In qualitative research, the "doability" of the design - the degree to which each part of the study is realisitc and appears to have a high probability of success in implementation
Grounded Theory
An iterative qualitiative approach that includes initial generative questions, gathering qualitiative data, identifying theoretical concepts in data, reconsidering theoretical concepts, and so on, until a detailed theory is grounded in observation is achieved
Phenomenology
A philosphical perspective as well as an approach to qualitative methodology that focuses on people's subjective experiences and interpretation of the world
Relevance
The degree to which a study may make a practical contribution to a substantive area as well as the goodness of fit of methods to the study goals in all aspects of the design
Rigor
The soundness of the methods chosen and degree to which the design has accounted for potential problems in any stage of the research
Covariate
Variables you adjust for in your study
Factorial Designs
Designs that focus on the program or treatment, its components, and its major dimensions and enable you to determint whether the program has an effect, whether different subcomponents are effective and whether there are interactions in the effects caused by subcomponents
Fully Crossed Factorial Design
A design that includes the pairing of every combination of factor levels
Incomplete Factorial Design
A design in which some cells or combinations in a fully crossed factorial design are intentionally left empty
Interaction Effect
An effect that occurs when differences on one factor depend on which level you are on another factor
Level
In an experimental design, a subdivision of a factor into components or features
Main Effect
An outcome that shows consistent differences between all levels of a factor
Probabilistic Equivalence
The notion that two groups, if measured infinitely, would on average perform identically
Random Assignment
Process of assigning your sample into two or more subgroups by chance. Procedures for random assignment can vary from flipping a coin to using a table of random numbers to using the random number capability built into a computer
Randomized Block Design
Experimental designs in which the sample is grouped into relatively homogeneous subgroups or blocks within which your experiment is replicated. This procedure reduces noise or variance in data
Solomon Four-Group Design
This design has four groups. Two of th egroups receive the treatment and two do not. Furthermore, one of the treatment groups and one of the controls receive a pretest and the other two do not. Bgy explicitly including testing as a factor in the design, you can assess experimentally whether a testing threat is operating
Switching Replications Design
A two-group design in two phases defined by three waves of measurement. The implementation of the treatment is repeated in both phases. In the repetition of the treatment, the two groups switch roles: the original control group in phase 1 becomes the treatment group in phase 2, whereas the original treatment acts as the control. By the end of the study, all participants have received the treatment
Two-Group, Posttest-Only, Randomized Experiment
A research design in which two randomly assigned groups participate. Only one group receives the program, and both groups receive a posttest.
Double-Pretest Design
A design that includes two waves of measurement prior to the program
Nonequivalent Dependent Variables (NEDV) Design
A single-group pre-post quasi-experimental design with two outcome measures, where only one measure is theoretically predicted to be affected by the treatment and the other is not
Pattern-Matching NEDV Design
A single-group pre-post quasi-experimental design with multiple outcome measures where there is theoretically specified pattern of expected effects across the measures. To assess the treatment effect, the theoretical pattern of expected outcomes is correlated or matched with the observed pattern of outcomes as measured
Proxy-Pretest Design
A post-only design in which, after the fact, a pretest measure is constructed from preexisting data. This is usually done to make up for the fact that the research did not include a true pretest
Quasi-Experimental Design
Research designs that have several of the key features of randomized experimental designs, such as pre-post measurement and treatment-control group comparisons, but lack random assignments
Regression Discontinuity (RD)
A pretest-posttest program-comparison group quasi-experimental design in which a cutoff criterion on the preprogram measure is the method of assignment to group
Regression Line
A line that describes the relationship between two or more variables
Regression Point Displacement (RPD)
A pre-post quasi-experimental research design where the treatment is given to only one unit in the sample, with all units acting as controls. This design is particularly useful to study the effects of community-level interventions, where outcome data is routinely collected at the community level
Statistics
The process of estimating various features from data, often using probability theory
Threats to Internal Validity
Any factor that can lead you to reach an incorrect conclusion about whether there is a causal relationship in your study
Covariance
A statistical estimate of the degree to which two variables vary together. This is distinct from the idea of variance which estimates the variability of a single variable
RD Design
A pretest-posttest-comparison group quasi-experimental design in which acutoff criterion on the preprogram measure is the method of assignment to group
RE Design
The Randomized Experimental (RE) Design is characterized by one essential feature: the random assignment of participants to conditions
.05 Level of Significance
The significance level specifically, alpha is the Type 1 error, or the probability of concluding that there is a treatment effect, when, in reality, there is not
Alpha Level
Same as .05 Level of Significance
Boxplot
A boxplot (or box and whicker plot) is a graphic display invented by John Tukey that summarizes the distribution of as numeric vairable by showing the median and quartiles as a box and the extreme values as "whiskers" extending from the box
Central Tendency
An estimate of the center of a distribution of values. The most usual measures of central tendency are the mean, median, and mode
Codebook
A written description of the data that describes each variable and indicates where and how it can be accessed
Correlation
A single number that describes the degree of relationship between two variables
Correlation Matrix
A table of correlations showing all possible relationships among a set of variables. The diagonal of a correlation matrix always consists of 1's because there are the correlations between each variable and itself. Off-diagonal elements are the correlations of variables represented bu the relevant row and column in the matrix
Cross-Tabulation
A table that describes the frequency and/or percentage for all combinations of two or more nominal or categorical variables
Degrees of Freedom (df)
A statistical term that is a function of the sample size. In the t-test formula, for instance, the df is the number of persons in both groups minus 2
Descriptive Statistics
Statistics used to describe the basic features of the data in a study
Dispersion
The spread of the values around the central tendency. The two common measures of dispersion are the range and the standard deviation
Distribution
The manner in which a variable takes different values in your data
Double Entry
An automated method for checking data-entry accuracy in which you enter data once and then enter it a second time, with the software automatically stopping each time a discrepancy is detected until the data enterer resolves the discrepancy. This procedure assures extremely high rates of data entry
Exploratory Data Analysis
The use of graphic and other methods to examine relationships in a data set. EDA is especially helpful when trying to develop hypotheses about relationships and when examining distributions of variables by themselves or in relation to other variables
Fishing and the Error Rate Problem
A problem that occurs as a result of conducting multiple analyses and treating each one as independent
Frequency Distribution
A summary of the frequency of individual values or ranges of values for a variable
Imputation
Substituting an estimated value for a missing one so that an analysis can include the variable
Mean
A description of the central tendency in which you add all the values and divide by the number of values
Median
The middle number in a series of numbers or the score found at the exact middle or fiftieth percentile of the set of values
Mode
The most frequently occuring value in the set of scores
Pearson Product Moment Correlation
A particular type of correlation used when both variables measured at an interval level of measurement
Qualititative
The descriptive nonnumerical characteristic of some object. A qualitative variable is a descriptive nonnumerical observation
Range
The highest value minus the lowest value
Statistical Power
The probability of correctly concluding that there is a treatment or program effect in your data
Stem and Leaf Diagram
In a stem-and-leaf plot, each observed value is divided into two components - leading digits (the stem) and trainling digits (the leaves). Like the histogram, it shows the entire distribution of a variable, but in addition preserves all of the individual values in the display. The stem-and-leaf plot is one of the many graphic techniques developed by John Tukey
Symmetric Matrix
A square table of numbers that describes the relationships among a set of variables where each variable represents a row or column. Each value in the table represents the relationship between the row and column variable for that cell of the table. The table is "symmetric" when the relationship betweren a specific row and column variable is identical to the relationship between the same column and row. A correlation matrix is a symmetric matrix
Threat to Conclusion Validity
Any factor that can lead you to reach an incorrenct conclusion about a relationship in your observations
Variance
A statistic that describes the variability in the data for a variable. The variance is the spread of the scores around the mean of a distribution. Specifically, the variance is the sum of the squared deviations from the mean divided by the number of observations minus 1
Constant Comparison
The iterative and sequential process used when analyzing qualitative data that involves refinement of categories and interpretations based on increasing depth of understanding
Data Reduction
The systematic process undertaken to convert a set of raw data to a coded or summary form
Open-Coding
A phase of the grounded theory method where you consider the data in minute detail while developing some initial categories
Theoretical Saturation
The point at which the analyst or analysts agree that new data no longer adds new meaning. The analysis is saturated in the sense that it is complete and sufficient
Confidence Intervals
Technically, 1-alpha. The confidence interval is the probability of correctly concluding that there is no treatment effect
Dummy Variable
A variable that uses discrete numbers, usually 0 to 1, to represent different groups in your study in the equations of the GLM
Effect Size
An estimate of the effect of a treatment or program. The effect size is a signal to noise ration where the numerator (top) represents the effect you are trying to assess and the denominator (bottom) represents the variability or noise in the data
Error Term
A term in the regression equation that captures the degree to which the line is in error (that is, the residual) in describing each point
General Linear Model (GLM)
A system of equations that is used as the mathematical framework for most of the statistical analyses used in applied social research
Inferential Statistics
Statistical analyses used to reach conclusions that extend beyond the immediate data alone
Least Squares
The criterion for fitting a regression line so that you minimize the sum of the squares of the residuals from the regression line
Linear Model
Any statistical model that uses equations to estimate lines
Measurement Error
Any influence on an observed score not related to what you are attempting to measure
Model Specification
The process of stating the equation that you believe best summarizes the data for a study
p Value
the estimate of the probability for a test of an hypothesis. Usually the p value is compared to the significance level when testing a hypothesis. If the p value exceeds the designated significance level the alternative hypothesis is accepted; if it does not, the null hypothesis is accepted
Propensity Score Analysis
A statistical modeling approach for adjusting for selection bias by estimating the probability or "propensity" of assignment to treatment given a set of pre-program variables
Residuals
The vertical distance from the regression line to each point. The residual in regression analysis refers to the portion of the outcome or dependent variable that you cannot predict with your regression equation
Slope
The change in y for a change in x of one unit
Standard Error of the Difference
A statistical estimate of the standard deviation one would obtain from the distribution of an infinite number of estimates of the difference between the means of two groups
t-test
A statistical test of the difference between the means of two groups, often a program and comparison group. The t-test is the simplest variation of the one-way analysis of variance (ANOVA)
t-value
The estimate of the difference between the groups relative to the variability of the scores in the groups
Abstract
A concise description of a research study, usually displayed at the beginning of a research publication as a summary
Citation
A brief reference in the text of a research write-up to a specific source used in the article, such as another research article, website, book, etc. Each citation in a write-up should have a complete reference included in the reference section at the end of th earticle
Digital Repository
A publicly shared electronic archive for research reports and data
Distribution Media
In the context of research, it is the universe of possibilities for sharing a research report including all paper and electronic forms
Reference Database Program
A specialized kind of database program designed to help writers keep track of citations. It may include special tools for managing references from the point when a researcher downloads a citation from a bibliographic database to the writing of a manuscript
Reference
A complete description of a source that is relevant to your research, including authors, title, date, publisher, page numbers and location. References for a research write-up are usually all listed at the end of the article
Study Schema
A graphic display allowing the procedural steps of a study and indicating the number of participants at each step
Meta-Analysis
A structured empirical analysis that integrates and summarizes results of multiple research studies or evaluations
Research Synthesis
A structured empirical process of producing integrative summaries of a body of research
Cost-Effectiveness and Cost-Benefit Analysis
Economic assessments of the costs of achieving specific outcomes and of these costs weighed against the estimated benefits
Impact Evaluation
The formal empirical assessment of the overall effects (intended and unintended) of a program or technology
Outcome Evaluations
The formal assessment of whether a program or treatment caused the observed outcomes
Process Evaluations
A structured empirical assessment of the process of delivering a program or technology
Implementation Evaluation
A structured empirical process that assesses the degree to which a program or technology is implemented faithfully according to its conceptual specifications
Structured Conceptualization
Any structured empirical method that can be used to develop a conceptual model or theory, often as the basis for a research project or evaluation
Evaluability Assessment
A structured empirical process of assessing whether a formal evaluation is feasible in any specific context
Needs Assessment
A structured empirical process for assessing the needs for a program or intervention
Summative Evaluations
Evaluations that examine the effects or outcomes of some program or treatment
Formative Evaluations
Evaluations that strengthen or improce the object being evaluated. Formative evaluations are used to improve programs while they are still under development
Evaluation
The systematic acquisition and assessment of information to provide useful feedback about some object
Evolutionary Epistemology
A philosophical position that holds that all knowledge evolves through evolutionary processes of natural selection
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