Research Methods and Statistics

Created by Patricia_D_Carson 

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critical thinking

process of evaluating claims or hypotheses and making judgments about them on the basis of well-supported evidence

hypothesis

a prediction stated as a testable proposition, usually in the form of an if-then statement

variables

specific factors or characteristics that are manipulated and measured in research

data

numbers that represent research findings and provide the basis for research conclusions

operational definition

a statement of the specific methods used to measure a variable; a detailed explanation of the variable

theory

cluster of explanations of a phenomenon that help predict, explain, and control that behavior

naturalistic observation

method gathering descriptive information involving watching behaviors, without interfering, as they naturally occur

case study

used to collect descriptive data through the intensive examination of a phenomenon in a particular individual, group, or setting (particularly useful for rare or complex phenomena)

survey

questionnaire or interview administered to a large group; designed to obtain descriptions of peoples' behaviors/beliefs

correlational studies

research method that examines relationships between variables in order to analyze trends in data, test predictions, etc. (they do NOT discern cause and effect relationships)

experiment

the only research method to show causation, this involves obtaining a random sample of subjects and using control and experimental groups; allows a researcher to control the data-collection process

independent variable

controlled by the researcher, experienced by the control group, this is what the researcher thinks will HAVE an effect on some other behavior

dependent variable

behavior affected by another variable, it is observed and measured (usually before and after and experiment takes place)

experimental group

receives the critical part of the experiment (the independent variable)

control group

provides a baseline for comparison, does not receive critical treatment (independent variable)

experimenter bias

occurs when experimenters ask leading questions or otherwise search for evidence that supports their hypothesis and don't look for evidence that refutes it

random variable

a confounding variable in which uncontrolled factors affected the dependent variable along with or instead of the independent variable

random assignment

random distribution of participants to experimental or control groups - used to distribute the impact of uncontrolled variables randomly, and most likely evenly, across the groups, minimizing the chance they will distort the results

placebo effect

improvement caused by a participant's knowledge and expectations: can be from a treatment that contains nothing known to be helpful, but that nevertheless produces benefits because a person believes it will be beneficial.

confounding variable

any factor that affects the dependent variable, along with or instead of the independent variable

double-blind design

design for research in which neither the experimenter nor the subjects know who is in the experimental or control group

sampling

the process of selecing participants for research who are members of the population the researcher wishes to study

generalize

to apply the results of one's study to people beyond just the researcher's sample

representative sample

a group of subjects whose characteristics fairly reflect the characteristics of the population they belong to

random sample

a group of subjects selected froma population whose members all had an equal chance of being selected

biased sample

a group of research subjects selected froma population whose members did not all have an equal chance of being chosen

sampling error

part of a sampling process that results in a biased sample

convenience sample

when researchers draw participants from the populations that are readily available to them

twin studies

study the heredity-environment question by comparing the similarity seen in identical twins with those of nonidentical pairs

descriptive statistics

numbers that describe and summarize a set of research data

inferential statistics

set of mathematical procedures that help researchers learn if their research data reflects a true relationship or could be due to random chance

mode

measure of central tendency that is the value that occur most frequently in a data set

median

measure of central tendency that is the halfway point in a set of data

mean

measure of central tendency that is the arithmetic average of the scores in a set of data

range

measure of variability that is the difference between the highest and lowest values in a set of data

standard deviation

measure of variability that is the average difference between each score and the mean of the data set (demonstrates consistency)

correlation

the degree to which one variable is related to another

correlation coefficient

a statistic (r) that summarizes the strength and direction of a relationship between two variables

statistical significance

a term used to describe research results that have been shown by a statistical test to be UNLIKELY to be due to random chance

ethics

code used by psychologists dictating that they minimize discomfort or risk for research participants

hindsight bias

tendency to believe, after learning an outcome, that one would have foreseen it.

theory

set of assumptions used to explain phenomena & offered for scientific study

hypothesis

testable prediction, often implied by a theory

operational definition

statement of procedures used to define research variables which helps to enable replication

replication

repeating of research study to determine if its finding extends to other participants and circumstances

case study

descriptive research technique in which one person or a small group is studied in depth in hope of revealing universal principles

survey

research method in which info is obtained by asking many individuals a fixed set of questions

false consensus effect

tendency to overestimate extent to which others share our beliefs and behaviors

population

all cases in a group, from which samples may be drawn for a study

random sample

sample that fairly represents a population because each member has an equal chance of inclusion.

naturalistic observation

descriptive research that involves observing and recording behavior without trying to manipulate and control the situation.

correlation

measure of the extent to which two factors vary together which can be positive or negative or non

scatterplot

graphed cluster of dots, each of which represents the values of two variables. The slope of the points suggests the direction of the relationship between the two variables.

illusory correlation

perception of a correlation between variables where none exists.

experiment

research method in which investigator manipulates one or more factors (IV) to observe effect on some behavior or mental process (DV)

control condition

condition of experiment that contrasts with experimental condition and serves as a comparison for evaluating the effect of the treatment.

double-blind procedure

experimental procedure in which both research participants and research staff are ignorant about whether the research participants have received the treatment or a placebo.

experimental condition

condition of experiment that exposes participants to treatment, that is, to one version of the IV

placebo effect

experimental results caused by expectations alone; any effect on behavior caused by the administration of an inert substance or condition, which is assumed to be an active agent.

dependent variable

variable that may change in response to manipulations of the IV (what is measured)

independent variable

experimental factor that is manipulated; variable whose effect is being studied.

mean

arithmetic average of a distribution,

median

middle score in a distribution; half scores are above it and half are below it.

mode

most frequently occurring score(s) in a distribution.

range

difference between highest and lowest scores in a distribution.

standard deviation

computed measure of how much scores vary around the mean score.

statistical significance

statistical statement of how likely it is that an obtained result occurred by chance - expressed as p or sig.

Steps in the Research Process

1) select topic, 2) focus question, 3) design study, 4)collect data, 5) Analyze data, 6)interpret data, 7) inform others

What is a Research Question:

the organizing principle for an individual study. It clarifies exactly what the researcher wants to understand, describe, or explain

Characteristics of a Good Research Question:

1) It elicits an explanation or description, not an answer 2) It links contructs & suggests associations or relationships 3) It can be addressed w/ empirical evidence 4) It is focused and feasible

PICO approach

Patient/problem, intervention, comparison intervention, outcomes. Works best for quantitative designs

Confidence intervals:

allow us to use sample data to estimate a population value like the ture mean or the true proportion. EX: what is the true avg amount students spend weekly on alcohol

Hypothesis testing:

Allows us to use sample data to test a claim about a population, such as testing whether a population proportion or population mean = some #. EX: is the true avg amount that students spent weekly on alcohol $20

Null hypothesis:

always represents the status quo, i.e. the hypothesis that requires no change in current behavior.

Alternative hyposthesis

is the conclusion that the researcher is trying to make.

Using the PubMed database

Identify the key concepts in your research question. Example: Find citations about bronchodilators for treating asthma in children.The key concepts are bronchodilators, asthma and children Enter the significant terms into the search box. Press the Enter key or click Go

Currency

how up to date the information that is being used

Writing References in APA style

Author (alphabetical) month/year, journal name, article name, where it was retrieved

Difference between a literature review and a research paper

Research paper - supports your own argument. Literature review-summary and synthesis of the arguments and ideas of others

Literature review strategies

Find a focus - organize around an idea, Construct a working thesis statement, Organize: Basic categories include: Introduction Body Conclusions Organizing the body methods include: Chronological, Thematic, Methodological

Reasons behind making outlines

Aids in the process of writing, Helps organize ideas

Purpose statement

a declarative sentence which summarizes the specific topic and goals of a document. It is typically included in the introduction to give the reader an accurate, concrete understanding what the document will cover and what he/she can gain from reading it. To be effective it should be: specific and precise, concise, clear, goal oriented

Thesis

The answer to the question is the thesis statement for the paper.

Types of Outlines

Alphanumeric, Full Sentence, Decimal

Keys to a Successful Presentation:

Define Objectives, Know Your Audience, Organize Your Presentation, Develop Visual Aids, Address Your Delivery, Develop Your Q&A, Check Out Your Environment

Scientific Structure

Report of Literature Search, Methodology/Techniques, Results, Interpretation/Discussion, Future Implications

The 3 step outline of a presentation

Step One: Tell them what you will tell them Step Two: Tell them Step Three: Tell them what you told them

Importance of visual aids

Increase Audience Interest, Focus Audience Attention, Induce Audience Participation, Reinforce Points of Emphasis, Increase Retention of Content

What % of what we learned is by sight?

87%

What % of what % of we learn is from what we see and hear

50%

What % of what we learn is by participation

70%

Effective delivery factors

Enthusiasm, Audience Bonding, Posture/Movement, Gestures, Eye Contact, Voice Quality

Hazards of presentations

Poor Introduction, Equipment Failure, Missing Materials, Lighting, Hecklers, Late Returners

Effective/Ineffective purpose statement: "The purpose of this paper is to describe the changes that are occurring in corporate America

ineffective: too vague

Ineffective/effective purpose statement:"The purpose of this report is to discuss the eating disorders Anorexia and Bulimia

Ineffective: to vague

ineffective/effective purpose statement: This article will cover the different ways a company can become organized

Ineffective: obscure and misleading

Ineffective/effective purpose statement:This paper will describe four common causes of co-worker conflict in organizations and explain how to use a five-step procedure to constructively manage this conflict

effective: very specific

Ineffective/effective purpose statement: This report will explain how supervisors can use four planning strategies to improve employee productivity in the workplace

effective: very specific

Ineffective/effective purpose statment: This purpose of this report is to describe the main causes of traffic congestion in Seattle

Effective: leaves no doubt about the reporters main purpose

Research Ethics

3 Principles: Beneficence, Respect, Justice 6 Norms: Valid Research Design, Researcher Competence, Identify Consequences, Appropriate Sample Selection, Voluntary Informed Consent, Inform Participants whether harm will be compensated

Undoing Deception

Debriefing, Dehoaxing, Guarding Privacy & Confidentiality of Participants, Obtain fully informed consent

Autonomy

the right or condition of self-government

Beneficence

maximizing good outcomes for science, humanity, and the individual research participants & minimizing or avoiding unnecessary risk, harm, or wrong

Voluntary Participation

without threat or undue inducement

Informed Consent

agree to participate without threat or undue inducement knowing what a reasonable person in the same situation would want to know before giving consent & explicitly agreeing to participate

Random Assignment

assignment of subjects/participants so that both the criteria of equal probability and independence are fullfilled

Random Selection

the selection of each unit is independent of the selection of any other unit; every person in a population has equal probability of being selected

Defining Characteristics of Experimental Research

1) change x & observe y 2) control as many variables as possible, manipulate 1 to yield causation 3) results are interpreted as "true" within a certain degree of probability

Confounds

other factors that can affect an outcome in an experiment- not measured, but explains results

Independent Variable

a variable that is managed or manipulated in an experiment to determine whether it affects a dependent variable

Dependent Variable

a variable that is observed or measured in an experiment to determine whether it is affected by an independent variable

Criterion Variable

a variable being studied in a correlational project, regarding the extent to which it is correctly predicted by one or more predictor variables

Predictor Variable

a variable being studied in a correlational project, regarding the extent to which it correctly predicts one or more criterion varialbes

Internal Validity

an aspect of design validity: the extent to which all extraneous variables are controlled, enabling results to be interpreted unambiguously regarding the people, setting & occasions studied

External Validity

Generalizability of results to other people, times, places & circumstances than those studied, as relevant to the project's mission

Null Hypothesis

a statistical hypothesis of "no difference" or "no relation" in populations represented by the samples

Experimental Hypothesis

a statement that expresses a prediction about what the answer to a research question will be or an idea about the phenomenon being studied

Control Group

composed of subjects that are alike in all preexisting characteristics to the experimental group, except for the treatment experienced by the experimental group

Correlational Coefficient

a statistical measure expressing the relationship between two or more variables with a single number between 1 & 1, inclusive

Correlational Research

investigate relationships among variables studied

Cross Sectional Research

"cohort design" based on independent group comparisons among samples who have reached different stages of development at the time the study is conducted

Longitudinal Research

studies the same people at different times; inferences about the developmental variable are based on repeated measures comparisons

Reliability

a measure of consistency

Validity

evidence that an instrument/study measures the construct it claims to

Case Study

descriptive research approach- studies intensively a given social unit (individual, group, institution, etc.)

Ethnographic Research

research method designed to describe & analyze practices & beliefs of cultures & communities; involves entering into first hand interaction with people in their everyday lives

Participatory Research

participants participate in the research process- Cooperative Inquiry or Participatory Action Research

Focus Group

a semistructured group interview procedure

Descriptive Research

describes what is without inferring causation

Threats to Internal Validity

1) History 2) Maturation 3) Testing 4) Instrumentation 5) Statistical Regression 6) Differential Selection 7) Experimental Mortality 8) Selection-Maturation Interaction 9) Experimental Treatment Diffusion 10) Compensatory Rivalry by Control Group- John Henry Effect 11) Compensatory Equalization Diffusion 12) Resentful Demoralization of the Control Group

Stratified Sampling

a method of sampling in which the population is subdivided according to one or more stratification variables before the sample is selected, each subdivision of the population is represented by a corresponding subdivision in the sample

Intensity Sampling

sites or individuals are selected in which the phenomenon of interest is strongly represented , but not necessarily extreme

Simple Random Sampling

random sampling applied to the entire frame at once; requires access to the entire population-every person has equal probability of being selected

Cluster Sampling

a procedure in which intact groups rather than individuals are sampled

Probability Sampling

sample is drawn in such a way that makes it probable that the sample is approximately the same as the population on the variables to be studied (SRS, systematic, stratified, cluster, multistage)

Convenience Sampling

a set of individuals studied in a research project because they are conveniently available, without regard to whether they are representative of a population

Operational Definition

experimentally accessible population; moving from a theoretical definition of a concept to something that can be measured; practical, measurable

Conceptual Definition

a theoretical definition of a concept that uses other constructs to explain the meaning

Constructivist Paradigm

reality is socially constructed, research-attempt to understand from POV of those experiencing ; research can not be separated from researcher bias

Postpositivist Paradigm

rational, empiricist, value free & causal nature of what we observe can be concluded; prefer experimental design & random assignment

Percentile Scores

refer to the percentage of cases in a norm sample who scored below an individual's score

Standardized Tests

have instructions for uniform administration, procedures and norms & have been put through rigorous developmental cycles

Measures of Central Tendency

mean, median, mode

Meaning of p Values

Power-ability to detect deviations from the null hypothesis; ex. .5% chance will detect statistical significance if it is present

Statistical Significance

of a magnitude rarely obtained by random sampling from populations for which the null hypothesis is true; probability that the difference in scores occurred because of reasons other than error

Norm Referenced Tests

individuals performances can be compared with the norm group; results from 1 or more large samples with known characteristics

ANOVA

analysis of variance- a test for the significance of differences among three of more means; parametric

T test

inferential statistical test- used to compare two groups; parametric

Chi Square

test of statistical significance for categorical date; non-parametric