©M.A. Oct 2025
Units 5-26 of Research Methodology and Descriptive Statistics (Pre-master Psychology)
Welcome hardworking students.
This is a summary of all the microlectures given by Henk van der Kolk for Research Meth and
Descriptive Statistics. Good luck. Hope this helps.
Sincerely,
M.A.
Pre-master Psychology student 2025
Contents:
Unit 5: Conceptualization, constructs as combinations of facets ................................................2
Unit 6: Operationalization and data collection ..........................................................................5
Unit 7: measuring constructs using content analysis .................................................................7
Unit 8 – Two aspects of data quality .........................................................................................9
Unit 9 – Displaying univariate data in R ................................................................................. 13
Unit 10: Summarizing Ratio Variables ................................................................................... 14
Unit 11: Distributions and Z-scores in R................................................................................. 17
Unit 12 – Causality and bivariate causal hypotheses ............................................................... 18
Unit 13 – Visualizing and analyzing bivariate relationships in R.............................................. 21
Unit 14 – Causality and the effect of third variables ................................................................ 22
Unit 15 – Research designs for testing causal hypotheses ......................................................... 25
Unit 16 & 17– Elaboration: analyzing multivariate relationships using tables .......................... 29
Unit 19 – Sampling ................................................................................................................ 32
Unit 20 – first steps towards inference: certainty about means ................................................ 38
Unit 23 – Normal distribution ................................................................................................ 40
Unit 24 – Describing the association between two variables ..................................................... 42
Unit 26: Data collection methods and measurement ................................................................ 44
1
,©M.A. Oct 2025
Unit 5: Conceptualization, constructs as combinations of facets
Facets= dimensions or traits
Concept and constructs
Many concepts are simple.
• How much money is in your bank
• How much energy a windmill produces
Examples of constructs (relationships between facets)
• And: Bachelor -> Dichotomy
• Not: Gender -> typology
• Or: Democracy -> dichotomies or indices (ordinal/scale)
• Missing: Personality
Relation concepts to observations
Concepts/constructs / term: this is the deductive way
• We identify facets of these constructs
• The indicators we find measuring the constructs
• The indicators are used in the measurement procedure (observations)
The inductive way
Starting with observations
Arriving at the construct at the end
Everyone uses constructs
Violence, personality
• Constructs can refer to units and variables
• For example: State
A bachelor
Bachelor is a variable characterizing people
Conceptualize: People are or are not bachelors
• Dichotomy
The facets of the variable:
The relationship between facets and terms (conceptualization using AND)
Term: being a bachelor or not
• Married or not
• Over 18 or not
• Male or not
AND: a set of necessary and sufficient conditions
• If we miss information about one of the facets we cannot tell
• If we have information about the three facets, we can tell
Gender as a dichotomy
• Meanings of Sex/gender
• Term: Male or female
2
,©M.A. Oct 2025
Variables
• XX or XY chromosome
• Characteristics at birth
• Category in passport
Typology is a way to categorize four examples instead of two
• Operationalization is for example: man, woman and ‘other’
Democracy
Underlying facets:
• Rule or law
• Popular elections
OR (only sufficient conditions) dichotomy (family resemblance)
Missing: just a set of somehow related variables
Example: personality
Personality is a set of variables and not combined in any way
Conceptualization dimensions
Personality
Political efficacy
Constructs consist of facets
• For example, we have 5 dimensions in personality: openness, conscientiousness, extraversion,
agreeableness and neuroticism
• Missing relationship
Four types of relationships
Missing: a set of somehow related variables
NOT: creating (matrix) typologies
AND: necessary and sufficient conditions
OR: family resemblance (sufficient conditions)
NOT
Attention Seeking
Unstable Stable
Neuroticism
Reflective
Extraversion
Attention seeking, reflective, unstable and stable are traits they characterize individuals
1. As a set of (five) (unrelated) traits, OR
2. As a set of types (based on dichotomous traits)
Eysenck’s study of personality (choleric, sanguine, phlegmatic and melancholic)
3
, ©M.A. Oct 2025
Efficacy
New concept: political efficacy
The feeling that individual’s political action does or can have an impact upon the political process.
The OR relationship with ordinal
Indices, typologies and scales
Measure theoretical constructs
First, they must conceptualize → operationalized and then measured
Example
‘What are the mathematical abilities of students at this university’
➔ Some theoretical variables are simply observed (gender, age)
➔ Others are complex, like construct (bachelor, democracy, IQ, mathematical abilities)
Making clear what you mean with the variables means your conceptualizing
Content validity
If all the aspects of a construct are included in the operationalizations: the content is valid
Combining indicators into one construct
• Index
• Typology
• Scale
We have 60 mathematical questions that go in one construct
Index:
Creating an ordinal variable by simply adding up’ answers
Typology
Creating a nominal variable, by using the intersection of two or more variables
• Correct answers to adding.
• Correct answers to multiplication
Make an X and Y axel and put them there, you get four types
Scale
Creating an ordinal variable by combining answers (as in an index)
- After checking the empirical relationships between the answers and sometimes by considering
these relationships
Gutman scale
• Also make an X Y axel
• But maybe there is no- one in this category.’
• But only 3 types instead of 4
4
Units 5-26 of Research Methodology and Descriptive Statistics (Pre-master Psychology)
Welcome hardworking students.
This is a summary of all the microlectures given by Henk van der Kolk for Research Meth and
Descriptive Statistics. Good luck. Hope this helps.
Sincerely,
M.A.
Pre-master Psychology student 2025
Contents:
Unit 5: Conceptualization, constructs as combinations of facets ................................................2
Unit 6: Operationalization and data collection ..........................................................................5
Unit 7: measuring constructs using content analysis .................................................................7
Unit 8 – Two aspects of data quality .........................................................................................9
Unit 9 – Displaying univariate data in R ................................................................................. 13
Unit 10: Summarizing Ratio Variables ................................................................................... 14
Unit 11: Distributions and Z-scores in R................................................................................. 17
Unit 12 – Causality and bivariate causal hypotheses ............................................................... 18
Unit 13 – Visualizing and analyzing bivariate relationships in R.............................................. 21
Unit 14 – Causality and the effect of third variables ................................................................ 22
Unit 15 – Research designs for testing causal hypotheses ......................................................... 25
Unit 16 & 17– Elaboration: analyzing multivariate relationships using tables .......................... 29
Unit 19 – Sampling ................................................................................................................ 32
Unit 20 – first steps towards inference: certainty about means ................................................ 38
Unit 23 – Normal distribution ................................................................................................ 40
Unit 24 – Describing the association between two variables ..................................................... 42
Unit 26: Data collection methods and measurement ................................................................ 44
1
,©M.A. Oct 2025
Unit 5: Conceptualization, constructs as combinations of facets
Facets= dimensions or traits
Concept and constructs
Many concepts are simple.
• How much money is in your bank
• How much energy a windmill produces
Examples of constructs (relationships between facets)
• And: Bachelor -> Dichotomy
• Not: Gender -> typology
• Or: Democracy -> dichotomies or indices (ordinal/scale)
• Missing: Personality
Relation concepts to observations
Concepts/constructs / term: this is the deductive way
• We identify facets of these constructs
• The indicators we find measuring the constructs
• The indicators are used in the measurement procedure (observations)
The inductive way
Starting with observations
Arriving at the construct at the end
Everyone uses constructs
Violence, personality
• Constructs can refer to units and variables
• For example: State
A bachelor
Bachelor is a variable characterizing people
Conceptualize: People are or are not bachelors
• Dichotomy
The facets of the variable:
The relationship between facets and terms (conceptualization using AND)
Term: being a bachelor or not
• Married or not
• Over 18 or not
• Male or not
AND: a set of necessary and sufficient conditions
• If we miss information about one of the facets we cannot tell
• If we have information about the three facets, we can tell
Gender as a dichotomy
• Meanings of Sex/gender
• Term: Male or female
2
,©M.A. Oct 2025
Variables
• XX or XY chromosome
• Characteristics at birth
• Category in passport
Typology is a way to categorize four examples instead of two
• Operationalization is for example: man, woman and ‘other’
Democracy
Underlying facets:
• Rule or law
• Popular elections
OR (only sufficient conditions) dichotomy (family resemblance)
Missing: just a set of somehow related variables
Example: personality
Personality is a set of variables and not combined in any way
Conceptualization dimensions
Personality
Political efficacy
Constructs consist of facets
• For example, we have 5 dimensions in personality: openness, conscientiousness, extraversion,
agreeableness and neuroticism
• Missing relationship
Four types of relationships
Missing: a set of somehow related variables
NOT: creating (matrix) typologies
AND: necessary and sufficient conditions
OR: family resemblance (sufficient conditions)
NOT
Attention Seeking
Unstable Stable
Neuroticism
Reflective
Extraversion
Attention seeking, reflective, unstable and stable are traits they characterize individuals
1. As a set of (five) (unrelated) traits, OR
2. As a set of types (based on dichotomous traits)
Eysenck’s study of personality (choleric, sanguine, phlegmatic and melancholic)
3
, ©M.A. Oct 2025
Efficacy
New concept: political efficacy
The feeling that individual’s political action does or can have an impact upon the political process.
The OR relationship with ordinal
Indices, typologies and scales
Measure theoretical constructs
First, they must conceptualize → operationalized and then measured
Example
‘What are the mathematical abilities of students at this university’
➔ Some theoretical variables are simply observed (gender, age)
➔ Others are complex, like construct (bachelor, democracy, IQ, mathematical abilities)
Making clear what you mean with the variables means your conceptualizing
Content validity
If all the aspects of a construct are included in the operationalizations: the content is valid
Combining indicators into one construct
• Index
• Typology
• Scale
We have 60 mathematical questions that go in one construct
Index:
Creating an ordinal variable by simply adding up’ answers
Typology
Creating a nominal variable, by using the intersection of two or more variables
• Correct answers to adding.
• Correct answers to multiplication
Make an X and Y axel and put them there, you get four types
Scale
Creating an ordinal variable by combining answers (as in an index)
- After checking the empirical relationships between the answers and sometimes by considering
these relationships
Gutman scale
• Also make an X Y axel
• But maybe there is no- one in this category.’
• But only 3 types instead of 4
4
