Methods and Statistics
Summary
M&S Summary Chapter 1
Definition scientific research:
“Scientific research is systematic, controlled, empirical, amoral, public, and critical investigation of
natural phenomena. It is guided by theory and hypotheses about the presumed relations among such
phenomena.”
Empirical-analytical paradigm = criterion to distinguish different kinds of research. Is the standard
approach. Two types; positivism and critical rationalism. Both types share the idea of discovering
lawful generalizations / phenomena.
- Positivism: Positivists claim that it is possible to make statements from factual observations
towards a theory. Based on the observations made, we may generalize towards a general
principle by means of induction. (All birds I have seen are also perceived by me to be singing,
so all birds sing.)
- Critical rationalism: Those within this school of thought oppose the inductive statements
mentioned above: even if I see masses of birds and they all sing, I still cannot say with
certainty that the supposed general principle is true. Can be used to show that a general
statement is not true falsification principle. If there is one bird in my sample that doesn’t
sing the theory is false. Problem 1; you could have done an invalid observation. Problem 2;
the general statement can be adapted to these new found observations and is therefore still
not completely rejected.
Critical paradigm = research as it is can’t state a truth because social factors aren’t accounted for in
the current way of researching. Social context is a problem for research for instance.
To get insight into natural phenomena, the phenomena must be measurable by a researcher.
Operationalization = process of making phenomena, behaviour or constructs measurable.
Concept-as-defined = the test, questionnaire, observation
Concept-as-intended = the theoretical construct
If the theoretical construct is given a good approximation, we speak of an adequate or valid
measurement.
A construct must be correctly operationalized in order to arrive at observations that are not only
valid (a good approximation of the abstract construct, you measure what needs to be measured) but
also reliable (observations must be more or less identical when measurement is repeated).
Instrument validation = validity and reliability of measurements is crucial and essential; this type of
research itself is meant to yield valid and reliable instruments that are a good operationalization of
the abstract construct-as-intended.
,Descriptive research = the researcher mostly aims for a description of the phenomenon. There are
different types of descriptive research:
- Correlational research: a correlation is found between possible causes and possible effects
The essential difference between descriptive and experimental research lies in the question as to
cause and effect. Based on descriptive research, a causal relationship between cause and effect
cannot be properly established.
Experimental research = Experimental research is characterized by the researcher’s systematically
manipulating a particular aspect of the circumstances under which a study is conducted. The
advantage of experimental research is that we may usually interpret the research results as the
consequence or effect of the experimental manipulation. Because the research systematically
controls the study and varies just one aspect of it. Different study types:
- Randomized / true experiment = random assignment of participants to conditions. best
method to exclude any non-relevant differences between the conditions of treatment.
- Quasi-experimental research = a particular aspect (such as teaching method) is indeed
systematically varied, but in which participants or groups of students are not randomly
assigned to the experimental conditions.
Laboratory research (experimental) = an aspect of reality is manipulated in a fully controlled
environment. The experiment is not likely to be disturbed by a starting engine or a downpour, but it
is less of a natural environment. It is more artificial.
Field research (experimental) = an aspect of reality is manipulated in an uncontrollable environment.
Many things can happen in the field that may influence the research results, but remain outside of
the researcher’s control. Causes more of a natural environment for the participants.
quantitative research seeks to understand the causal or correlational relationship between variables
through testing hypotheses, whereas qualitative research seeks to understand a phenomenon within
a real-world context through the use of interviews and observation
M&S summary chapter 2
empirical studies = pursue the goal of establishing connections between (supposed) causes and their
(supposed) effects or consequences. The researcher would like to know whether one variable has an
influence on another. Best way is experiment, because the outcome of a good experiment forms the
strongest possible evidence for a connection between the variables investigated.
In experimental research, the effect of a variable manipulated by the researcher on some other
variable is investigated. Hypothesis is prediction of the effect.
Variable = a particular kind of property of objects or people: a property that may vary, i.e., take
different values.
Regarding individuals: their length, their weight, shoe size, speaking rate, number of siblings,
number of children, political preference, income, sex, popularity within a group, etc.
Independent variable = the variable that brings out the investigated effect. Reason for experimental
and control group.
, Dependent variable = The variable that is effected by the independent variable. It is dependent on
this variable. This is also sometimes called the response or score. The responses of participants
change because of the change in the independent variable. (not cause and effect though, more of a
connection between the independent and dependent variable).
A scientific belief must be properly motivated and justified and must be coherent with other beliefs.
a proper scientific statement or theory ought to be falsifiable or refutable or testable, it must have
the possibility to be wrong.
Induction problem = it’s impossible to generalize a statement from a number of specific cases.
Null hypothesis (H0) = a very general hypothesis stating all of this is that. (all swans are white). The
H1 hypothesis is the statement that this is not true. (A black swan has been found). falsification
Falsification = we gain knowledge by rejecting (falsifying) hypotheses, and not by accepting
(verifying) hypotheses. The hypothesis has been proven wrong.
‘Earth’s climate is warming up’ is a good example of a statement that is becoming increasingly
immune to falsification, and, therefore, is becoming increasingly stronger.
The empirical cycle: not always all phases, depends on purpose of research
Observation = the researcher constructs a problem. The
researcher forms an idea of possible relationships between various (theoretical) concepts or
constructs. Could be based on case studies and certain phenomena in a small amount of cases.
Induction = Having started from specific observations, the researcher now formulates a hypothesis
that they suspect is valid in general. A specific case had been observed and has now lead to the
formulation of the hypothesis.
The hypothesis’ empirical content must be clearly described, so the hypothesis must be
specific enough on about who the hypothesis is. The type or class of observations must be
properly described.
a hypothesis also has to be logically coherent: the hypothesis has to be consistent with other
theories or hypotheses.
Three types of hypotheses:
1. Universal-deterministic hypotheses = all A’s are B’s – all swans are white. Validity can never
be truly proven because you cannot examine all cases.
2. Deterministic existential hypotheses = there is some A that is B. If a researcher can
demonstrate that there exists one A that is B, the hypothesis has been verified. However,
