Chapter 10- The Concept of Measurement Flashcards
Measurement
the process of assigning numbers or labels to persons, objects, or events in accordance with specific rules for representing quantities or qualities of attributes
Rule
a guide, a method, or a command that tells a researcher what to do
Measurement Process
- Identify Concept of interest
- Develop a construct
- Create a constitutive definition
- Develop an operational definition
- Create a measurement scale
- Evaluate the reliability and validity of the scale
- Utilize the scale
- Collect research findings
Construct
specific types of concepts that exist at higher levels of abstraction than do everyday concepts
Constitutive definition
a statement of meaning of the central idea or concept under the study, establishing its boundaries; also known as theoretical, or conceptual, definiton
Operational definition
specifies which observable characteristics will be measured and the process for assigning a value to the concept
Construct Equivalence
how people see, understand, and develop measurements of a particular phenomenon
Scale
set of symbols or numbers so constructed that the symbols or numbers can be assigned by a rule to the individuals (or their behaviors/attitudes) to whom the scale is applied
Nominal scales
partitions data into categories that are mutually exclusive and collectively exhaustive, implying that every bit of data will fit into one and only one category and that all data will fit somewhere on the scale;
uses numerals to identify objects, individuals, events or groups
Ordinal scales
scales that maintain the labeling characteristics of nominal scales and have the ability to order data
in addition to identification, provides information about the relative amount of some characteristic possessed by an event, object, etc, (order)
Interval scales
contain all the features of ordinal scales with the added dimension that the intervals between the points are equal
Ratio scales
have all the characteristics of other scales as well as a meaningful absolute zero or origin so that magnitudes can be compared arithmetically
What are 8 errors in validity of measurements
- A true difference in the characteristic being measured
- Differences due to stable characteristics of individual respondents such as personality, values, and intelligence
- Differences due to short-term personal factors such as mood swings, health problems etc.
- Differences caused by situational factors such as distractions or others present in the interview situation
- Differences resulting from variations in administering the survey
- Differences due to the sampling of items included in the questionnaire
- Differences due to the sampling of items included in the questionnaire
Differences due to a lack of clarity in the measurement instrument - Differences due to mechanical or instrument factors
Reliability
the degree to which measures are free from random error and, therefore, provide consistent data
what are 3 ways to assess reliability?
test-retest reliability, the use of equivalent forms, and internal consistency