Chapter 2
Answers to Before You Go On Questions
1. What are the two core beliefs of a science? The two core beliefs to science are (1) the
universe operates according to certain natural laws, and (2) these laws are discoverable and
testable.
2. What is the difference between inductive and deductive reasoning? Deductive reasoning is a
process that starts with broad principles and applies them in specific situations to prove many
smaller truths; an example would be using the Pythagorean Theorem to calculate the length
of a side of a right triangle. Inductive reasoning is a process where controlled, direct
observations are used to generate broad conclusions and, over time, these conclusions
achieve a non-biased truth about the laws of the universe.
3. What is the difference between a hypothesis and a theory? A theory is based upon
observations that lead researchers to develop ideas about the laws that govern processes and
behaviours. However, a sound scientific theory must first be proven. Therefore, researchers
create hypotheses (specific statements that are objectively falsifiable—meaning they can be
disproved). So think of a hypothesis as a prediction that can be proved true or false through
scientific method.
4. What is the hypothetico-deductive method? The hypothetico-deductive method is a process of
scientific investigation where scientists begin with an educated guess about how the world
works and then design small, controlled studies or observations to support or invalidate that
hypothesis.
5. What are the four goals of psychology? As a science, psychology shares four primary goals
with all other branches of modern science: describing, explaining, predicting, and controlling
the objects of study. However, it is important to note that there are differences between
psychology and the physical sciences in that the search for elements of mental processes and
behaviours is complicated by constantly shifting human factors.
6. What is the main difference between psychology and pseudopsychology? Although
pseudopsychology attempts to answer fundamental questions about human nature and
behaviour, just as psychology does, pseudopsychology does not make use of the scientific
method.
7. Which variable is controlled or manipulated by an experimenter? In an experiment, a
researcher will use different levels of an independent variable in an effort to change a
condition or event that relates to his or her hypothesis. By manipulating or controlling the
independent variable, a researcher hopes to affect the dependent variable—the condition or
event the researcher expects to change as a result of varying the independent variable.
8. What are three descriptive research methods used in psychology? The three descriptive
research methods used in psychology are (1) the case study (focuses on a single person or
subject), (2) naturalistic observations (researchers watch as unobtrusively as possible while
people behave as they normally would), and (3) surveys (a series of questions asked by the
researcher in a descriptive study; can be done in person, over the phone, or by email or a
written questionnaire). Each of the descriptive methods have their own strengths and
weaknesses and differ in their goals, sample sizes, and the extent to which we can generalize
their results back to an entire population.
9. Which research method allows research to say that one variable causes another? An
experimental design, especially one that uses random assignment, will allow a researcher to
make causal attributions about any significant results revealed. That is, significant group
differences on the dependent variable in an experiment can be said to have been caused by
differences in levels of the independent variable.
10. What two pieces of information does a correlation coefficient give about the relationship
between variables? A correlation coefficient gives us both the direction (a negative
correlation versus a positive correlation) and size or strength of the relationship between the
variables (how far away from 0 and toward either +1 or –1 the correlation coefficient is).
This tells us how well we can predict one variable if we know the other.
11. What do the mean and standard deviation tell you about scores of a group? In order to
describe the differences between the scores of experimental groups and control groups,
researchers calculate the mean and standard deviation of each group. The mean is the
arithmetic average of the scores of all participants in a group. The standard deviation is a
statistical index of how much scores vary within a particular group. The mean tells us about
the typical magnitude of whatever we are measuring within the group, and the standard
deviation tells us how spread out the scores are within the group.
12. What do t-tests tell experimenters? After determining the mean and standard deviation,
researchers are then able to better understand and compare research groups. Psychologists
typically compare means using statistical procedures known as t-tests (for two groups). This
procedure looks both at the mean differences and at the variance within the groups, as well as
at the size of the groups. The t-test is also known as a significance test because it measures
whether the differences found between groups are statistically significant; that is, whether the
apparent differences (in the sample studied) likely reflect real or genuine differences in the
general population.
13. What does a research ethics board do? Research ethics boards must be established by any
institution wishing to conduct research. These boards review all proposals for research
projects to ensure that they adhere to the ethical guidelines and standards set by the
appropriate regulatory body.
14. What is informed consent and how does it relate to debriefing? Informed consent requires
that researchers provide as much information as possible about the purpose, procedures,
risks, and benefits of a study to its participants so that they can make informed decisions
about whether they want to be involved in the study or not (Nagy, 2011). However, because
participants cannot always be given full prior knowledge of the purposes and goals of a study
(their responses within the study could be influenced by prior knowledge), researchers are
required to offer a debriefing to participants at the end of the study. This also provides
participants with opportunities to raise additional questions about the study in which they
took part.