Define reliability and validity in your own words. Briefly
describe the different types of reliability and...
Define reliability and validity in your own words. Briefly
describe the different types of reliability and validity, including
why it is important to conduct a study that is reliable and
valid.
Solutions
Expert Solution
Reliability is the degree to which an assessment tool produces
stable and consistent results.
Types of Reliability:-
Test-retest reliability is a measure of reliability obtained by
administering the same test twice over a period of time to a group
of individuals. The scores from Time 1 and Time 2 can then be
correlated in order to evaluate the test for stability over
time.
Example: A test designed to assess student learning in
psychology could be given to a group of students twice, with the
second administration perhaps coming a week after the first. The
obtained correlation coefficient would indicate the stability of
the scores.
Parallel forms reliability is a measure of reliability obtained
by administering different versions of an assessment tool (both
versions must contain items that probe the same construct, skill,
knowledge base, etc.) to the same group of individuals. The scores
from the two versions can then be correlated in order to evaluate
the consistency of results across alternate versions.
Example: If you wanted to evaluate the reliability of a
critical thinking assessment, you might create a large set of items
that all pertain to critical thinking and then randomly split the
questions up into two sets, which would represent the parallel
forms.
Inter-rater reliability is a measure of reliability used to
assess the degree to which different judges or raters agree in
their assessment decisions. Inter-rater reliability is useful
because human observers will not necessarily interpret answers the
same way; raters may disagree as to how well certain responses or
material demonstrate knowledge of the construct or skill being
assessed.
Example: Inter-rater reliability might be employed when
different judges are evaluating the degree to which art portfolios
meet certain standards. Inter-rater reliability is especially
useful when judgments can be considered relatively subjective.
Thus, the use of this type of reliability would probably be more
likely when evaluating artwork as opposed to math problems.
Internal consistency reliability is a measure of reliability
used to evaluate the degree to which different test items that
probe the same construct produce similar results.
A)Average inter-item correlation is a subtype of internal
consistency reliability. It is obtained by taking all of the items
on a test that probe the same construct (e.g., reading
comprehension), determining the correlation coefficient for each
pair of items, and finally taking the average of all of these
correlation coefficients. This final step yields the average
inter-item correlation.
B)Split-half reliability is another subtype of internal
consistency reliability. The process of obtaining split-half
reliability is begun by “splitting in half” all items of a test
that are intended to probe the same area of knowledge (e.g., World
War II) in order to form two “sets” of items. The entire test is
administered to a group of individuals, the total score for each
“set” is computed, and finally the split-half reliability is
obtained by determining the correlation between the two total “set”
scores.
Validity refers to how well a test measures what it is
purported to measure. While reliability is necessary, it alone is
not sufficient. For a test to be reliable, it also needs to be
valid. For example, if your scale is off by 5 lbs, it reads your
weight every day with an excess of 5lbs. The scale is reliable
because it consistently reports the same weight every day, but it
is not valid because it adds 5lbs to your true weight. It is not a
valid measure of your weight.
Face Validity ascertains that the measure appears to be
assessing the intended construct under study. The stakeholders can
easily assess face validity. Although this is not a very
“scientific” type of validity, it may be an essential component in
enlisting motivation of stakeholders. If the stakeholders do not
believe the measure is an accurate assessment of the ability, they
may become disengaged with the task.
Example: If a measure of art appreciation is created all of the
items should be related to the different components and types of
art. If the questions are regarding historical time periods, with
no reference to any artistic movement, stakeholders may not be
motivated to give their best effort or invest in this measure
because they do not believe it is a true assessment of art
appreciation.
Construct Validity is used to ensure that the measure is
actually measure what it is intended to measure (i.e. the
construct), and not other variables. Using a panel of “experts”
familiar with the construct is a way in which this type of validity
can be assessed. The experts can examine the items and decide what
that specific item is intended to measure. Students can be involved
in this process to obtain their feedback.
Example: A women’s studies program may design a cumulative
assessment of learning throughout the major. The questions are
written with complicated wording and phrasing. This can cause the
test inadvertently becoming a test of reading comprehension, rather
than a test of women’s studies. It is important that the measure is
actually assessing the intended construct, rather than an
extraneous factor.
Criterion-Related Validity is used to predict future or current
performance - it correlates test results with another criterion of
interest.
Example: If a physics program designed a measure to assess
cumulative student learning throughout the major. The new measure
could be correlated with a standardized measure of ability in this
discipline, such as an ETS field test or the GRE subject test. The
higher the correlation between the established measure and new
measure, the more faith stakeholders can have in the new assessment
tool.
Formative Validity when applied to outcomes assessment it is
used to assess how well a measure is able to provide information to
help improve the program under study.
Example: When designing a rubric for history one could assess
student’s knowledge across the discipline. If the measure can
provide information that students are lacking knowledge in a
certain area, for instance the Civil Rights Movement, then that
assessment tool is providing meaningful information that can be
used to improve the course or program requirements.
Define reliability and validity in your own words. Briefly
describe the different types of reliability and validity, including
why it is important to conduct a study that is reliable and
valid.
Define reliability & validity, describe and separate the
three methods for demonstrating validity. talk about the
relationship between validity and reliability
Describe in your own words the different types of withholdings
that you will withhold from an employees gross pay when doing
payroll. Additionally, describe the types of payments that an
employer may make regarding payroll for employees.
Hedge Transaction Types Briefly explain, in your own words,
three of the hedge transaction types. Describe in which situations
each would be used and why.
Hedge Transaction Types
Briefly explain, in your own words, three of the hedge transaction
types. Describe in which situations each would be used and why.
Reminder: Your initial posting should be 250-500
words
In your own words, briefly define health literacy and describe
one variable in literacy that affects patient understanding and
adherence to provider advice.
Validity, bias, reliability.
Give your own example of a measurement process that is valid but
has large bias.
Also, give your own example of a measurement process that is
invalid but highly reliable.
Define validity and reliability as they pertain to employee
testing. Describe how these two terms/concepts apply to substance
abuse screening in the workplace.