For multi-year summaries, MMARS offer 4 different types of comparisons:
Method #1) Non-matched students:
This is sometimes referred to as a cross-section, and compares, for each year, DIFFERENT sets of students. It is the default choice for “standard” reports like Performance Level Distributions and At-or-Above Proficient Summaries across multiple years.
Example: 2016-2017 Grade 8 students at a middle school. The reports will compare the "Class of 2017" (8th grade in 2017) with the Class of 2016 and Class of 2015. Each year represents a different group of students (unless anyone was retained).
Method #2) Matched students:
This compares, for each year, the SAME set of students, and includes only students with data for all selected years.
Example: 2016-2017 Grade 8 students at a middle school. The reports will compare the 2017 8th grade students vs. those SAME students' scores in 2016 and 2015 (when they were in grades 7 and 6). This compares exactly the same set of students; any student not having data ALL of the compared years (such as a student who transferred into the district during grade 7) is not included.
Method #3) Grade Cohort:
This is similar to Matched Students, but it is not per-pupil longitudinally matched. This compares/follows the same "class" of students, that changes somewhat, based on mobility (some students come and some leave). In other words, if there were zero mobility, then the Grade Cohort would be the same as Matched Students; think of this group as Matched Students, but without the strict exclusion rules for a student that does not have data for each of the selected years. So, it is generally the same group of students, followed for multiple years. This is what the CDE refers to as a "Cohort".
Example: 2016-2017 Grade 8 students at a middle school. The reports will compare the 2017 8th grade students vs. 2016 7th grade vs. 2015 6th grade. These students are peers, but the make-up of the group changes somewhat each year, based on mobility. All students in each year/grade are included.
Since this method "follows" a graduating class, it is by definition available only "by Grade". In other words, you can't run it schoolwide or districtwide cohort reports with multiple grade levels.
Method #4) Per-Year Pre/Post Matched Students:
These are used by our Improvement/Decline and Pre/Post Summaries. This is the same logic as "Matched Students," but here it is applied independently for each pair of years.
Example: 2016-2017 Grade 8 students at a middle school. The reports will compare the 2017 8th grade students vs. those SAME students' (7th grade) scores in 2016. It will also compare 2016 8th grade students vs. those SAME students' (7th grade) scores in 2015. For each pair of years, the "anchor" group changes and each separate 2-year comparison is using the exact same set of students, and only those with both pre and post scores.
This is particularly useful for evaluating teacher effectiveness at improving students' SBAC scores. For example, a multi-year report for a 5th grade teacher would show, for each year, the change in performance of students instructed by that teacher for that year. We compare the scores of the "outgoing" students vs. those same students' scores when they first arrived in the class (from the prior SBAC testing).
- Improvement / Decline, Pre/Post Summary, Pre/Post Summary with PL Detail all use method #4, because, by definition, they are comparing sets of students over the course of only 2 years.
- Performance Level and At-or-Above reports offer #1, #2, and #3.
- Cluster Performance is available by #1 only. This is because as students are promoted from grade to grade the cluster/goal/skill content changes, and this content is not comparable from year to year. For any fixed grade level (over different years) you can compare different sets of students.
- SBAC Claim Performance reports offer #1, #2, and #3. While Claims are effectively the same entity as Clusters (a skill that is subordinate to a subtest), Claims don't change from grade to grade, so we are able to compare in various ways.