Science & The Snapshot
Read more about the science behind The Snapshot.
Summary of Research
Extensive research and pilot testing was conducted in the envisioning and development of The Snapshot. Read more about the many ways we utilized the indepdendent school community in the creation of this groundbreaking assessment.
An overview of the research and development of The Snapshot.
Reliability is the tendency of test scores to be consistent on two or more testing occasions. The primary question one would ask when inquiring about reliability is: “how likely is the test taker to obtain the same score if he/she were tested over and over and over?” If a test has high reliability, the test takers would tend to obtain similar scores on another occasion of testing, assuming that the test taker’s knowledge or ability level does not change between different occasions of testing.
Reliability is the tendency of test scores to be consistent on two or more testing occasions.
Test validity refers to the degree to which evidence and theory exist to support the interpretation of test scores for particular purposes (AERA, APA and NCME, 2014). It is important to note that we validate a test score for a particular use (e.g., admission, placement), and that validity is not the property of a test in and of itself. This means that as opposed to talking about a test as simply valid or not valid, one should instead state, for example, “There is a great deal of validity evidence to support the use of The Character Skills Snapshot scores for independent school admission and/or placement decisions.” This also represents the notion that validity is a matter of degree and not absolute. It is therefore very important to gather validity evidence over time to either enhance, confirm or contradict previous findings.
Validity is a unified concept, yet there are multiple types of validity evidence that may contribute to the demonstration of validity. These types of evidence may include evidence based on test content—the relationship between the content of a test and the construct or characteristic it is intended to measure (Content Validity). Evidence based on internal structure refers to the degree to which test items and test components conform to the construct (e.g., score reliability, relationship of items and test dimensionality, etc.) (Construct Validity). Another type of validity evidence is based on relations to other variables, such as measures of criteria that the test is expected to predict (e.g., First Year GPA) or relationships to other tests measuring related constructs (Criterion Validity).
Test validity refers to the degree to which evidence and theory exist to support the interpretation of test scores for particular purposes.
Preliminary Validity Data
The relationships described herein explain correlations between the skills measured by The Snapshot and some kind of outcome (e.g., GPA) or relevant personal characteristic (e.g. happiness). Correlations present relationships between two or more concepts that are descriptive, not predictive. While the findings are promising, they should not be interpreted as an indication that one thing causes the other. Data on 608 students from 8 schools were used to examine these relationships. Data were from the Snapshot field trial and should not be considered representative of the larger Snapshot or SSAT populations. As a result, these findings may not generalize beyond this study. A largescale study investigating these relationships with students who completed The Snapshot between September 25, 2017 and July 29, 2018 is ongoing and the findings from that study will be provided when available.
A research study to understand the relationships between the skills measured by The Snapshot and a set of key academic, school engagement, and social-emotional outcomes.