PSYC 270 Exam 2

the effort to discover, and increase human understanding of how the physical world works

"it has always been this way"
(way of attaining knowledge)

"it feels true"
(way of attaining knowledge)

"the _____ says its true"
(way of attaining knowledge)

"it makes sense logically"
(way of attaining knowledge)

"I observed it to be true"
(way of attaining knowledge)

Science uses both ______ and ______

interrelated set of concepts that is used to explain a body of data and make predictions about the results of future experiments

specific predictions that are derived from theories

essential goal of experiment

Science is not defined by...

an investigation in which at least one variable is manipulated by the researcher.

occurs when you select an IV and another variable varies with it

variables that cannot be manipulated by the investigator

we have less confidence in our conclusions when we cannot manipulate the ______

can theoretically take on any value within a range of values

Ex. Height in inches

take on a limited number of values

Ex. Gender, Year in school

The numbers have only the property of identity

Ex: jersey numbers, M/F, ethnicity

Indicates rank ordering, distances between attributes do not have any meaning

Adding or multiplying are meaningless (thus you can not use a mean)

Ex: rank order of student preference for Coke, Pepsi, Vinegar

A scale that indicates an amount (but there is no 0 point), distance between attributes does have meaning

Averages, SDs are meaningful but not ratios

Ex: Virtually all psychological measurements (e.g. IQ scores, likert ratings), the distance from 30-40 is same as distance from 70-80 (but 80 degrees is not
twice as hot as 40 degrees)

A scale that has equal intervals with a true zero

Many forms of measurement in physics are ratio, but this is rare in psychology

Ex: You have $25 in your bank account, Bill Gates has $3,246,294,387.07 in his account. You have
7.7x10-9 the amount of money that he has in his account.

Unplanned and uncontrolled factor(s) that can arise in an experiment and affect the outcome

An unwanted factor that affects groups differently and make it difficult to know what caused changes in the dv

A researcher manipulates an independent variable and controls for possible confounds; make CAUSAL statements

No explicit manipulation of variables; no differential treatment of groups or differential treatment of one participant at different times; do NOT allow researchers to determine exactly how changes in one or more variables produce, or cause, changes in another variable.

Examples: naturalistic observation,correlational, ex-post facto/quasi-experimental

Comparing existing groups (classification variables) to see if they differ

In-depth research of a single individual or a few people without any manipulation of the environment

Using existing information (e.g., documents, newspaper reports, etc.) to address behavioral issues

Studying people in their natural environment descriptively (without numerical analyses) and holistically

Recording naturally occurring behavior without intervention or manipulation of variables

A definition of a variable in terms of the actual procedures used by the researcher to measure and/or manipulate it

Example: concept social behavior: “the number
of people who spend time in groups,” “the number of times an individual approaches another individual to interact with him or her,” or “the score on a
questionnaire that asks about social behaviors”

refers to the process of assigning arbitrary symbols (usually numbers), according to a predetermined set of rules, to different events or object

potential problems with observational studies:

External validity can be high during _________

degree to which the results of a study apply to individuals and realistic behaviors outside the study

degree to which a study provides causal information about behavior (with alternative explanations of
the data ruled out)

degree to which the results of a study can be replicated under similar conditions

goal of naturalistic observation:

with multiple observers, there must be training and checking to ensure that behaviors are coded in the same way

Pros of archival research

Cons of archival research

scores are indicative of the psychological construct the survey was designed to measure

determining the validity of the scores of a survey by examining the relationship between the survey scores
and other established measures of the behavior of interest

Ex: the SAT is used as a college
entrance exam because scores on this test
have been tested with academic achievement in college (specifically, first-year gpa, 4-year gpa, and college graduation)

A biased sample that doesn’t accurately reflect the population of interest can reduce the _______ of the
survey measure

a sampling error that occurs when individuals chosen for the sample do not respond to the survey, biasing the sample

Way to increase reliability:

the scores are similar each time a participant takes the survey

a form of reliability that tests relationships between scores on different items of a survey

a measure of reliability (internal consistency) based on the average correlations between pairs of items on a survey

there is potentially a difference in the people who respond to a survey compared to those who do not; can be alleviated by offering incentives (problem with survey)

Class of biasing influences that cause people to distort the truth, e.g. social desirability (problem with survey)

Participants may not know the answers (problem with survey)

2 questions in 1 question

Avoid _______ questions

Avoid _______ wording

people favor option presented last; also, the answer to a question might be influenced by the question asked before it.

Example: divorce survey

How to fix an order effect: