Research and Methods

Question 1

Assignment

Answer 1

The process by which participants are put into either an experimental or a control group.

Random assignment means that each participant has an equal chance of being placed into any group.

It limits the effects of confounding variables based on differences between people.

Using random assignment diminishes the chance that participants in the two groups differ in any meaningful way.

Question 2

Confounding Variables

Answer 2

Any difference between the experimental and control conditions (such as time of day), except for the independent variable, that might affect the dependent variable.

An experiment allows the researcher to manipulate the independent variable and control for confounding variables.

Question 3

Experiment

Answer 3

The only research method that can show a causal relationship.

Allows the researcher to manipulate the independent variable and control for confounding variables.

A confounding variable is any difference between the experimental and control conditions (such as time of day), except for the independent variable, that might affect the dependent variable.

Experiments compare at least two groups: an experimental group and a control group that differ based on the independent variable.

Question 4

Stratified Sampling

Answer 4

A process that allows a researcher to ensure that the sample represents the population on some criteria, such as age or race.

For instance, if a researcher thinks that participants of different racial groups might respond differently, he or she would want to make sure that each race is represented in the sample in the same proportion that it appears in the overall population.

In other words, if 500 of the 1,000 students in a school are Caucasian, 300 are African American, and 200 are Latino, in a sample of 100 students the researcher would want to have 50 Caucasians, 30 African Americans, and 20 Latinos.

Question 5

Random Sampling (Selection)

Answer 5

A method of selecting a sample from a population.

Every member of the population has an equal chance of being selected. Random sampling (selection) increases the likelihood that the sample represents the population and that one can generalize the findings to the larger population.

If you are choosing a random sample of students from a high school, you might list all the students in alphabetical order by their last name and choose every fifth student to be in your sample.

Question 6

Population

Answer 6

The group from which a sample is selected.

The population includes anyone or anything that could possibly be selected to be in the sample.

The goal in selecting a sample is that it represents a larger population.

If you are studying how high school students at a particular school feel about online privacy, you might choose a random ample of 100 high school students from the population of all high school students at that particular school.

Question 7

Sampling

Answer 7

The individuals on whom the research is conducted are called participants (or subjects), and the process by which participants are selected is called sampling.

To select a sample (the group of participants), first identify the population from which the sample will be selected.

The population includes anyone or anything that could possibly be selected to be in the sample. The goal in selecting a sample is that it represents a larger population.

Random sampling (selection) means that every member of the population has an equal chance of being selected.

Random sampling (selection) increases the likelihood that the sample represents the population and that one can generalize the findings to the larger population.

Question 8

Reliability

Answer 8

Good research is both valid and reliable.

Research is reliable when it can be replicated. For example, a personality test that returns the same results each time a person takes it would be considered reliable.

If the researcher conducted the same research in the same way, the researcher would get similar results.

I related concept is validity: research is valid when it measures what the researcher set out to measure; it is accurate.

Question 9

Validity

Answer 9

Good research is both valid and reliable.
research is valid when it measures what the researcher set out to measure.

For example, a personality test that accurately describes a person’s true personality traits would be considered valid.

The related concept is reliability: Research is reliable when it can be replicated; it is consistent.

Question 10

Operational Definitions

Answer 10

An explanation of how variables are measured.

Two variables need to be operationally defined in the hypothesis “Watching violent television programs makes people more aggressive”:

• What programs will be considered violent?
• What behaviors will be considered aggressive?

Question 11

Hypothesis

Answer 11

A statement that expresses a relationship between two variables.

In an experimental hypothesis, the dependent variable depends on the independent variable.

In other words, a change in the independent variable will produce a change in the dependent variable.

For instance, consider the hypothesis that watching violent television programs makes people more aggressive.

In this hypothesis, watching television violence is the independent variable since the hypothesis suggests that a change in television viewing will result in a change in the dependent variable, aggression.

In testing a hypothesis, researchers manipulate the independent variable and measure the dependent variable.

Question 12

Theory

Answer 12

Aims to explain some phenomenon and allows researchers to generate testable hypotheses with the hope of collecting data that support the theory.

Hypotheses often grow out of theories.

Question 13

Basic Research

Answer 13

Research that explores questions that are of interest to psychologists but are not intended to have immediate, real-world applications.

An example of basic research is an investigation into which areas of the brain are involved in seeing color.

The other category of research is applied research, which is conducted in order to solve practical problems.

Question 14

Applied Research

Answer 14

Research that psychologists conduct to solve practical problems, such as investigating how people can best resolve personality conflicts at work.

Research that has clear, practical applications.
The other category of research is basic research, which explores questions that are of interest to psychologists but are not intended to have immediate, real-world applications.

Question 15

Scatter Plot

Answer 15

A graph of correlated data.

Graphs pairs of values, one on the y-axis and one on the x-axis.

For instance, the number of hours a group of people study per week could be plotted on the x-axis, while their GPAs could be plotted on the y-axis. The result would be a series of points called a scatter plot.

The closer the points come to falling on a straight line, the stronger the correlation.

A line that slopes upward, from left to right, indicates a positive correlation.

A downward slope indicates a negative correlation.

Question 16

Hindsight Bias

Answer 16

Tendency of people, upon hearing about research findings (and many other things), to think that they knew it all along.

After an event occurs, it is relatively easy to explain why it happened.

The goal of scientific research, however, is to predict what will happen in advance.

An example of hindsight bias: Someone reads a study indicating that married people tend to live longer. This person says, “That’s obvious! Everyone already knew that!”

Question 17

APA Ethical Guidelines for Animal Research

Answer 17

The APA (American Psychological Association) established ethical guidelines for human and animal research.
Ethical psychological studies using animals must meet the following
requirements:
* Have a clear scientific purpose.
* Care for and house animals in a humane way.
* Acquire animal subjects legally.
* Design experimental procedures that employ the least amount of suffering feasible.

Question 18

Survey Method

Answer 18

Involves asking people to fill out surveys.

Often used to gather opinions or attitudes and for correlational research.

Response rate refers to the proportion of a surveyed group who respond to and return a survey.

Question 19

Naturalistic Observation

Answer 19

A research method that involves observing participants in their natural habitats without interacting with them.

The goal is to get a realistic and rich picture of the participants’ behavior.

Cannot establish cause and effect relationships between variables.

Jane Goodall used naturalistic observation to study chimpanzees by observing them in their natural environment and taking careful notes on their behaviors.

Question 20

Case Study

Answer 20

A research method used to get a full, detailed picture of one participant or a small group of participants.

For instance, clinical psychologists often use case studies to present information about a person suffering from a particular disorder.

Allows researchers to get the richest possible picture of what they are studying, but the focus on a single individual or small group means that the findings cannot be generalized to a larger population.

Question 21

Descriptive Statistics

Answer 21

Ways of describing a set of data.

Measures of central tendency are a common descriptive statistic. (Mean, Median, Mode)

The mean is the average of all the scores in a distribution.

The median is the central score in the distribution.

The mode is the score that appears most frequently.

Question 22

Measures of Variability

Answer 22

A type of descriptive statistical measure that attempts to depict the diversity of the distribution.

Range, variance, and standard deviation are measures of variability.

Range is the distance between the highest and lowest score in a distribution.

Variance and standard deviation are closely related; standard deviation is simply the square root of the variance.

Both measures essentially relate the average distance of any score in the distribution from the mean.

Question 23

Normal Curve

Answer 23

A bell-shaped curve that represents a distribution of scores that is normally distributed (a few scores at the low end and high end of the distribution, with most of the scores clustered around the mean).

Approximately 68 percent of scores in a normal distribution fall within one standard deviation of the mean.

Approximately 95 percent of scores fall within two standard deviations of the mean.

Almost 99 percent of scores fall within three standard deviations of the mean.

Question 24

Statistical Significance

Answer 24

Scientists have decided that 5 percent (0.05) is the cutoff for statistically significant results. This means that in a statistically significant experimental result, the chance that a result occurred by chance is 5 percent or less.

Researchers use inferential statistics to determine whether results are statistically significant.

Question 25

Inferential Statistics

Answer 25

Statistics that can determine whether or not findings can be appl to the larger population from which the sample was selected.

Related to the concept of statistical significance: Scientists have decided that 5 percent (0.05) is the cutoff for statistically signif results.

This means that in a statistically significant experimenta result, the chance that a result occurred by chance is 5 percent or less.

Question 26

APA Ethical Guidelines for Human Research

Answer 26

The APA (American Psychological Association) established ethical guidelines for human and animal research.

Any type of academic research must first propose the study to the ethics board or institutional review board (IRB) at the institution.

Guidelines for human research include:
* Coercion
* Informed consent
* Anonymity /confidentiality
* Lack of risk
* Debriefing procedures

Question 27

Correlation

Answer 27

A statistical measure of a relationship between two variables.

Correlation does not imply causation: Just because two variables are correlated does not mean that one variable causes the other.

Can be either positive or negative. A positive correlation between two variables means that the presence of one variable predicts the presence of the other. A negative correlation means that the presence of one variable predicts the absence of the other.

The strength of a correlation is expressed by a number called a correlation coefficient, which ranges from -1 to +1 where -1 is a perfect, negative correlation and +1 is a perfect, positive correlation.
(.07-.09=Highly correlated)
(.05-.07=Moderatly correlated)

DIFFERENT THAN STATISTICAL SIGNIFICANCE AT .05

Height is positively correlated with shoe size. The number of cigarettes smoked per day is negatively correlated with longevity.

Question 28

Hawthorne Effect

Answer 28

Being selected to be in a group of people to participate in an experiment will affect the performance of that group, regardless of what is done to those individuals.

Just selecting a sample of people and including them in an experiment will affect the performance of the sample, as the chosen participants will try to please the researcher.
Control groups help to control for the Hawthorne effect.

Question 29

Participant Bias

Answer 29

Also called Response Bias

The tendency for subjects to behave in certain ways based on their perception of an experiment.

It can be controlled using a single-blind procedure (when participants do not know whether they are assigned to an experimental or control group) or a double-blind procedure (when neither the participants nor the researcher is aware of who is in the experimental or control groups while the experiment is going on).

Question 30

Double-Blind Procedure

Answer 30

Method followed such that neither the participants nor the researcher are aware of who is in the experimental or control groups while the experiment is going on.

Double-blind procedures control for both experimenter bias (researchers treating members of the experimental and control groups differently) and participant bias (the tendency for subjects to behave in certain ways based on their perception of an experiment).

Question 31

Experimenter Bias

Answer 31

The unconscious tendency for researchers to treat members of the experimental and control groups differently increases the chance of confirming their hypothesis.

Experimenter bias is not a conscious act. If researchers purposely distort their data, it is called fraud, not experimenter bias.

Using a double-blind procedure can eliminate experimenter bias.

A double-blind occurs when neither the participants nor the researcher are able to affect the outcome of the research.