HDFS 2001W Exam 2

Population

The entire group of people a study is designed to investigate

Sampling frame

The list of quasi-list of units composing a population from which a sample is selected

sampling unit

an element or person considered for selection into a sample

sample

the collection of sampling units selected from the population

Representativeness

the degree to which a sample reflects the characteristics of the population

Parameter

A summary description of a variable in a population

Statistic

A summary description of a variable in a sample

Sampling Error

Error caused by observing a sample instead of the entire population

confidence level

the estimated probability that a population parameter lies within a confidence interval

confidence interval

the range of values within which a population parameter is estimated to lie

Probability sampling

sampling in which every element has a known chance of selection

Random selection

Every person has an equal chance of being selected independently of others

Simple random sampling

Sampling units are assigned numbers and selected randomly

Systematic Sampling

Selecting every nth unit after a random starting point

Stratified Sampling

Dividing a population into groups and sampling from each group

Nonprobability sampling

Sampling methods that do not rely on probability theory

Convenience Sampling

Selecting people who are easiest to access

Purposive Sampling

Selecting people because they have characteristics relevant to the study

Snowball Sampling

Participants help identify additional members of a hard to reach population

Quota Sampling

Sampling designed to match the caracteristics of subgroups within a population

Ethics

Standards or codes of behavior expected of a profession or group

Informed Consent

Participation based on a full understanding of risks and procedures

Respect for Persons

Treating people as autonomous individuals capable of making their own decisions

Beneficence

minimizing harm and maximizing benefits

Justice

fair selection of participants and fair distrubution of risks and benefits

Anonymity

The reseracher cannot identify which response belongs to which participant

Confidentiality

The researcher knows participant identities but agrees not to reveal them

Deception

Withholding information or misleading participants for research purposes

Debriefing

Informing participants about the true purpose of a study after participation

Institutional Review Board (IRB)

Committee responsible for reviewing research involving human participants

Voluntary Participation

Participation free from force or coercion

Questionnaire

Instrument designed to collect information for analysis

Respondent

Person who answers survey questions

Open ended question

Participant provides their own answer

Close ended question

Participant selects from researcher provided responses

Double Barreled Question

A question asking two things at once

Loaded Question

A question worded to encourage a particular response

Negative wording

Question wording that involves negatives and may cause confusion

Response rate

number of respondents divided by the number selected for the survey

Self administered questionnaire

survey completed by the respondent without an interviewer

Interview Survey

Survey conducted by an interviewer asking respondents questions

Secondary Analysis

Reanalysis of data collected by another researcher

Social desirability

Tendency of participants to give socially acceptable answers rather than truthful ones

Experiment

Research involving manipulation of a variable and observation of outcomes

Independent variable

variable manipulated by the researcher

dependent variable

Variable measured to determine the effect of the IV

Experimental Group

Group receiving the treatment or stimulus

Control group

Group not receiving the treatment and used for comparison

Random assignment

Assigning participants to groups by chance

Matching

Pairing subjects on important variables before assigning them to groups

Double Blind experiment

Neither particpants nor researchers know who receives treatment

Cofounding variable

Uncontrolled variable that could explain the results

Quasi Experiment

Experiment lacking key features such as random assignment

One shot case study

one group studied after treatment

One group pretest-posttest design

One group measured before and after treatment

Static group comparison

comparing a treatment group to a group without treatment

Historical events

outside events occuring during the study affect outcomes

Maturation

Natural changes in participants over time affect outcomes

Testing effect

Taking a test influences later performance

Instrumentation

Changes in measurement methods affect results

Regression to the mean

Extreme scores naturally move closer to average over time

Selection bias

Groups differ before treatment begins

Experimental Mortality

Participants drop out before study completion

Demoralization

Control group becomes discouraged because they don’t receive treatment

Evaluation Research

Applied research assessing the effectiveness of programs, policies, or interventions

Program Evaluation

Determines whether a program achieves its intended goals

Needs Assessment

Identifies the existence and extent of a problem

Cost benefit study

Examines whether benefits justify program costs

Monitoring study

Ongoing assessment of implementation and outcomes

Time Series Design

Repeated measurements over time before and after an intervention

Non equivalent control group

Comparison group not created by random assignment

Multiple Time Series Design

Multiple groups measured repeatedly over time

Social Indicators Research

Use existing social data to study social trends and issues

Generalization

Applying findings from a study to a broader population

External Validity

Extent to which findings generalize to other people, settings, and times

Volunteer Bias (Self-selection bias)

Volunteers differ from the larger population

Exact replication

Repeating a study using the same procedures

Conceptual Replication

Testing the same idea using different procedures

Meta Analysis

Statistical technique combining results from many studies