PSYC104 Chapter Notes - Chapter 7: Apgar Score, Intellectual Disability, Response Bias
21 May 2018
School
Department
Course
Professor
Measureet ad Saplig – Week Five
Readigs
What is Measurement?
Used in everyday life.
Very first measurement was Apgar score.
Formal study of measurement requires a development of quantification rules -> essential
guidance for a meaningful interpretation of numbers.
Meaningfully clarifies the relationship between physical characteristics such as weight or
height.
Systematic process of assigning numbers to characteristics or attributes of individuals
using a set of carefully selected and explicitly stated rules.
Use numerical values to assign groups (eye colour for example). It is systematic and
consistent.
Relation Between Measurement and Evaluation
Important for judging whether certain goals and objectives have been met.
Measuring something will lead to an evaluation about it – for example a teacher who
conducts tests to measure whether students are mastering the material. If they fail the goal,
then the teacher will need to establish why the objective has not been met and the reason for
the failure – to then administer other tests to assess things like physical characteristics such as
hearing tests or intelligence tests.
Objective -> Measurement -> Evaluation.
Evaluation -> forming judgments and making decisions from measurements.
Implications of Measurement
Measurement -> process of assigning numbers to characteristics or attributes of individuals.
Test Bias -> content bias and testing situation bias.
Content Bias -> when test items are more favourable toward one group of individuals
relative to another group. (if culture makes it difficult to understand passages or photos etc).
Testing Situation Bias -> a variety of external factors that influence test performance, such
as response bias, test-taking ability, examiner characteristics, and achieving motivations.
Test-taking ability can influence test performance because skilled test-takers employ
strategies.
- Testing situations can favour certain groups of students, it was found that Hispanic
students with low achievement test scores were wrongfully considered as students
with intellectual disabilities.
find more resources at oneclass.com
find more resources at oneclass.com
History of Measurement
Formal use of measurements date back as far as 3000 years ago. Oral school examinations
date back to the beginning of the 13th century and paper examinations in the 16th century.
Examination of individual differences began in the 19th century.
Karl Pearson – Pioneer of modern statistics:
a. The Pearson product-moment correlation that measures a relation between two
continuous variables such as height and weight;
b. Chi-square goodness of fit test that measures association of variables in two-way
tables.
Pioneer of individual test of intelligence – Alfred Binet.
Between the two world wars, a new field of study called psychometrics was introduced -> a
discipline focused on the theory and application of psychological measurement.
Psychometrics focuses on measurement and testing.
Rasch Models -> estimating the difficulty of an item, measuring a given characteristic, and
assessing individuals on particular characteristics.
Item Response Theory -> focuses on the relationship between the individual’s performance
on test items and the individual’s ability that is measured with the test.
- Individual abilities, skills, characteristics (response test items and item
characteristics).
Computerised Adaptive Testing -> assessment method that departs from administering a
fixed set of items to all test-takers because it allows for adjusting item difficulty to the ability
level of an individual.
- Correct items become more difficult.
- Greatest advantage is adjusting item difficulty to ability level of individual.
Levels of Measurement
Rationale for developing different levels of measurement is that the same number can
represent different characteristics.
In one context, the same numeric value for eye colour can also represent a maths test score
ranging from 0 to 30.
Four levels of measurement:
- Nominal
- Ordinal
- Interval
- Ratio
Four levels on the absence or presence of the four features:
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Formal study of measurement requires a development of quantification rules -> essential guidance for a meaningful interpretation of numbers. Meaningfully clarifies the relationship between physical characteristics such as weight or height. Systematic process of assigning numbers to characteristics or attributes of individuals using a set of carefully selected and explicitly stated rules. Use numerical values to assign groups (eye colour for example). Important for judging whether certain goals and objectives have been met. Measuring something will lead to an evaluation about it for example a teacher who conducts tests to measure whether students are mastering the material. Evaluation -> forming judgments and making decisions from measurements. Measurement -> process of assigning numbers to characteristics or attributes of individuals. Test bias -> content bias and testing situation bias. Content bias -> when test items are more favourable toward one group of individuals relative to another group. (if culture makes it difficult to understand passages or photos etc).
