Chapter 4 - Operationalization

Question 1

What is operationalization?

Answer 1

The development of specific definitions for all relevant factors related to the research topic of interest.

Operationalization turns vague or ambiguous concepts into detailed descriptions, which can be measured.

In order to operationalize, a researcher needs to identify indicators logically related to the concept of interest.

Question 2

What is an independent variable and dependent variable?

Answer 2

The independent variable is the one presumed to influence or cause the dependent variable.

Question 3

What is a mediating variable?

Answer 3

Sometimes called the intervening variable is something that influences the mechanism by which the IV affects the DV

A mediating variable may be a factor in WHY the IV-DV relationship exists in the first place.

Ex: If we think our intervention increases fruit and vegetable consumption by first increasing awareness of places to purchase food, this awareness would be considered a mediating variable.

Question 4

What is a moderating variable?

Answer 4

Moderating variables influence the strength or direction of the IV-DV relationship, and contextualize the effect between the IV and DV

Question 5

What is controlled variable?

Answer 5

Variables in research that are accounted for in different ways.

Controlling for the effects of variables is a common in public health research studies.

Researcher holds constant balances across groups, or neutralizes so it will not have an effect on the study.

Question 6

What is constant variable?

Answer 6

A constant variable has no variation. It is the same for all cases in a study, and helps control the effects of the variable.

Question 7

What is a positive correlation?

Answer 7

In a positive correlation, the value of the DV increases or decreases in the same direction as the IV. They both go up or they both go down.

Question 8

What is a negative correlation?

Answer 8

In a negative correlation, the variables change in opposite directions. As one goes up, the other goes down.

Question 9

What is a curvlinear correlation?

Answer 9

A curvlinear correlation occur when the relationship between the variables transforms at certain variable levels.

Question 10

What is a conceptual framework?

Answer 10

Outlines the theoretical or logical relationships among variables, and the progression from the IV to the DV.

The concepts and associated variables are organized and linked sequentially.

These frameworks are typically based on theory, evidence, or specific knowledge. Developing a conceptual framework is useful for considering proposed causal linkages between the variables in the study and other key factors potentially influencing the outcome (e.g. moderating variables(

When developing a conceptual framework, start with the end point and work backwards to identify the potential relationships among the variables.

Question 11

What is a hypotheses?

Answer 11

Hypotheses are statements that predict the nature and extent of relationships between variables based on your research question or research goals in quantitative studies.

Question 12

What is a null hypothesis?

Answer 12

The null hypothesis states that there no differences in attributes, effect, or relation between variables.

Question 13

What is an alternative hypothesis?

Answer 13

The alternative hypothesis affirms the existence of differences in attributes, effect, or relationship between variables.

Question 14

What is a good hypothesis?

Answer 14

Is based on your research question
Predicts the outcome of your research
Is directly related to the variables of interest
Is clear and concise
Is testable

Question 15

What is a dichotomous or binary variable?

Answer 15

Variables with only two attributes (completing intervention or not completing intervention)

Question 16

What are polychotomous variables?

Answer 16

Variables that have more than two attributes. They can be categorical or continuous.

Question 17

What is are the four levels of measurement?

Answer 17

1. Nominal - categories with no numerical value
2. Ordinal - scale in which each value is rank ordered in a way that is higher or lower than the previous value, but intervals are unknown or not equal
3. Interval - Scale in which values have order and equal intervals, without a true zero point
4. Ratio - scale in which values have order and equal intervals, with a true zero point.

Question 18

What is systematic error ?

Answer 18

Systematic error reflects an imprecise measure due to personal views or beliefs, and it affects the way people answer questions there by distorting true responses.

A common reason for systematic error due to bias is social desirability.

Question 19

What is social desirability?

Answer 19

Social desirability is when people tend to answer questions in a way that they think is socially acceptable.

Social desirability can result in acquiescent response set bias

Question 20

What is acquiescent response set bias?

Answer 20

Agreeing or disagreeing with all statements in order to provide what one thinks to be favorable responses.

Question 21

What is random error?

Answer 21

Responses may overestimate or underestimate true values in unpredictable ways , resulting in random error.

They are due to chance and have no consistent pattern.

Sometimes factors such as mood or circumstances influence responses.

Question 22

What are two ways to evaluate the quality of measurement procedures?

Answer 22

Reliability

Validity

Question 23

What is reliability?

Answer 23

The degree of consistency something has. The more reliable a measure is , the less likely it is to be impacted by random error.

Question 24

What types of test are there for reliability?

Answer 24

Test-retest reliability - measure of stability over time. Administering an instrument to collect data from a sample of people and having those same people complete the same measure again.

Internal consistency reliability - items throughout a measure should be consistent, whereby answers to questions relating to similar concepts should be highly associated with one another.

Inter-rater reliability - degree of agreement or consistency among multiple observers.

Question 25

What is validity?

Answer 25

Validity refers to the extent to which a measure is a true reflection of a real meaning of the concept it is intended to measure.

Question 26

What are the different types of validity?

Answer 26

Face Validity - subjective judgement of whether a measure is a reasonable way to measure some concept or if a logical relationship between the variable and the proposed measure exist.

Content Validity - the degree to which a measure covers an entire concept.

Criterion Validity - means scores on one measure are similar to scores on another measure of the same condition or criterion

Predictive Validity - occurs when scores on one measure can predict the scores on a similar measure.

Concurrent validity - a type of criterion validity that exist when scores on one measure are closely related to scores on another measure

Question 27

What is “r” in a linear association?

Answer 27

The sample correlation coefficient (r) is a measure of the closeness of association of the points in a scatter plot to a linear regression line based on those points, as in the example above for accumulated saving over time.

Question 28

What is internal validity?

Answer 28

The extent to which we can infer that the independent variable caused the dependent variable.

Question 29

What is external validity?

Answer 29

The extent to which the findings will generalize to other populations, settings, measures, and treatments

Question 30

What is measurement validity?

Answer 30

The quality of accuracy of individual measures or scores. The extent to which a score measures what it was intended to measure.

Question 31

How do we assess internal validity?

Answer 31

Equivalence of Groups on Participant Characteristics
Low - Groups very different, marked differential attrition
Medium - Some attempts to equate groups or groups found to be similar
High - Random assignments to groups and low attrition

Control of Experiences and Environment Variables (Contamination)
Low - Extraneous variables not controlled, no comparison group
Medium - Attempts to control experiences and environment
High - All extraneous variables controlled, eliminated, or balanced.

Question 32

How do we assess external validity?

Answer 32

Population
Low - actual sample unrepresentative of the theoretical population
Medium - some attempts to obtain good sample
High - actual sample representative of theoretical population

Ecological (naturalness of setting/conditions, extent to which results are restricted to a specific time in history)
Low - Unnatural setting, tester, procedures, and time
Medium - somewhat artificial (Questionnaire)
High - Natural setting, tester, procedures and time

Question 33

What are best practices for operationalization?

Answer 33

Look to past studies for operationalization and measures
Include members of the population of study in defining/modeling
Reduce chance for measurement error
Use existing valid and reliable measures if possible
Keep track of the process of operationalization and measure choice