SCI 201 Chapter 2 - Planning and Preparation (Terms)

Primary Sources

First-hand observation or an original work, describing original research

Secondary Sources

Second-hand observation that analyze, summarize or synthesizes primary sources

Paraphrasing

Writing the same points from a source in your own words with approximately the same phrasing, citing at the end

Summarizing

Extracting the main points from several sources and synthesizing them into brief statements that are much shorter than the original

Quoting

Directly quoting the source with exact wording and phrasing in quotation marks with a citation at the end

Authority

An aspect in source evaluation in which it is clearly from a well-recognized organized

Accuracy

An aspect in source evaluation where graphical and statistical presentations are clear, accurate, and consistent

Objectivity

An aspect in source evaluation in which the information is given as scientific knowledge, without bias or as advertisement

Currency

An aspect in source evaluation where the information is current or has findings that still hold to the day

Coverage

An aspect in source evaluation in which all the study information has all been provided

Specific Objectives

The essence or focal point of the entire project, unambiguously accounting for the only two possible outcomes of the study

Hypotheses

Educated or informed predictions based on prior knowledge, information from literature, discussions, and personal experience, including main variables expected to be true

Statistical Hypotheses

Both the possible outcomes of a hypothesis test that represent a default position or a difference/relationship

Null Hypothesis (H₀)

A statistical hypothesis that represents the default position in which a relationship cannot be drawn or a hypothesis cannot be proven correct

Alternative Hypothesis (H_a)

A statistical hypothesis that represents a predicted difference or relationship in variables based on the hypothesis

Non-Directional (Two-Tailed) Hypothesis

A hypothesis that tests whether there is any difference between two groups, regardless of what direction the difference is in

Directional (One-Tailed) Hypothesis

A hypothesis that tests whether there is any difference in a specific direction between two groups, where whether the value is greater or less matters

Study Units

Individuals or subjects about which information is required or on which data is recorded

Experimental Units

The study of units in an experimental study design

Units of Observation

The study of units in an observational study design

Population of Interest

The entire collection of all individuals that are of interest in the defined study and about which you want to make conclusions

Census

A sampling strategy in which data is collected about the entire population

Sample

A representative subset of the population from which measurements are taken

Variable

Any characteristic that varies from one study unit to another

Distribution of a Variable

All the values that a variable takes on in data collection

Categorical (Qualitative) Variables

Nominal, nonnumerical variables in which observations are recorded as frequencies classified by some quality or attribute in specific categories

Binary Categorical Variable

A type of categorical variable with only two possible categories

Ordinal Scale Variables

Ordinal, nonnumerical variables in which observations are recorded in categories without a constant interval between units as frequencies, that can be put in order from lowest to highest

Quantitative Variables

Ordinal, numerical variables in which observations are recorded as numerical values with a constant interval size between successive units

Discrete Quantitative Variables

A quantitative variable whose possible values only take on specific values, usually whole numbers that can be counted

Continuous Quantitative Variables

A quantitative variable whose values can take on an infinite number of possible values between any observed range, which is measureable

Ratio Scale

A scale used for quantitative variables in which a true zero point exists, making it possible to establish a ratio

Interval Scale

A scale used for quantitative variables in which there is no true zero point, making it impossible to establish a ratio

Indicator Variables

Categorical variables that are coded in order to convert them into quantitative variables, so that they can be analyzed using numerical hypothesis tests

Derived Variables

When a combination of categorical, ordinal, and quantitative variables are recorded and the values are combined to obtain one derived quantitative variable with combined units

Indices

When a combination of categorical, ordinal, and quantitative variables are recorded and the values are combined to obtain an index of measurements without units

Explanatory (Predictive) Variables

Variables of interest that are hypothesized to explain or affect other variables, but are not likely to be affected by other variables

Response (Dependent) Variables

Variables of interest that are hypothesized to be affected by the explanatory or independent variables

Extraneous Variables

Explanatory variables that are not of interest or are not related to the purpose of the study but may affect the response variable

Factors (Categorical Predictor Variables)

When explanatory variables are applied as treatments in an experiment or considered levels in an observational study

Spatial Aspects

The “where” component of research design, including the physical or virtual environment, and study sites or geographical locations

Temporal Aspects

The “when” component of research design, including the time period (year, month, time of day), and the frequency or period of time that variables are recorded

Random Sampling

The selection of individuals from a population without bias, such that all individuals have an equal chance of selection and the selection of individuals is independent

Simple Random Sampling (SRS)

A type of random sampling in which each individual is selected completely random and independently

Systemic Random Sampling

A type of random sampling in all other individuals following a randomly selected first individual are selected sequentially using some fixed increment

Stratified Random Sampling

A type of random sampling in which the population is divided into strata and proportionally allocated into each strata, and a SRS is taken in each stratum

Proportional Allocation

Proportional division of a sample into strata based on estimated density of the items or size of the strata

Multistage Random Sampling

A type of random sampling in which a large factor is sampled, then smaller and smaller subdivisions of the factor are sampled

Cluster Random Sampling

A type of random sampling in which random clusters of individuals in the sample are selected, then all the clusters are completely sampled

Degree of Variability

How spread out individual data points are from a central point within a single data set

Magnitude of Difference

The difference in amount or value between more than one group

Sampling Variability

The variation in characteristics of interest from one sample to another in the same population, existing regardless of how well random sampling is done

Convenience Sampling

A biased method of sampling in which the researcher selects individuals for sampling data due to ease of access or convenience

Voluntary Response Bias

A type of bias that occurs when the sample consists of volunteers who have willingly agreed and had the choice to participate

Response Bias

A type of bias that occurs when the prompting question in a social survey or the wording of a question seems to suggest a particular response favoured by the researcher

Nonresponse Bias

A type of bias that occurs when a large fraction of those initially sampled fail to respond to some or any of the questions

Incomplete Sampling Frame

A type of bias that occurs when some individuals or groups who belong to a certain sampling frame of reference are excluded due to experimental design error

Undercoverage

A type of bias that occurs when a portion of the population is not included or given a smaller representation than actually required

Observational Studies

A study in which estimation of population parameters is made based on how it occurs in nature or in society

Prospective Observational Study

A type of observational study in which subjects are identified beforehand and data is recorded as the observed event proceeds

Retrospective Observational Study

A type of observational study in which subjects and data are recorded after events have already occurred

Experimental Studies

A study in which the researcher sets up a random experiment by manipulating treatment groups in order to discover a cause-and-effect relationship between variables

Blinding

The act of anonymizing or hiding aspects of bias from those who could affect the results as well as those who could evaluate the results

Single-Blind Experiment

An experiment in which all individuals of either the participants or the researchers are blinded

Double-Blind Experiment

An experiment in which all individuals of the participants and the researchers are blinded

Placebo

Psychological effect of receiving a placebo, which may result in a subject responding to a treatment when they only received an inert placebo

Post Test Design

A type of experimental design in which the only the level of effect of the explanatory variable after treatment is measured in the control and experimental group

Pre Test-Post Test Design

A type of experimental design in which the both the level of effect of the explanatory variable before and after treatment is measured in the control and experimental group

Paired Design

An experimental design in which samples from two populations or the same individual is paired in space or time by some relationship