|
June 15, 2002
The Administrator's Guide to Data-Driven Decision Making (cont'd)
Data Mining: A Glossary of Terms
Analytical data is consolidated or summarized data used by decision makers to develop and implement new strategies. Examples of analytical data in schools include average daily student attendance, a longitudinal sequence of test scores, and the distribution of disciplinary incidents by hallway in a school building. Analytical data is based on information gleaned from transactional system data.
Decision support systems are those tools and technologies that help administrators make efficient and informed decisions about critical issues such as student and employee performance or financial resource allocation. While one common decision support system is the ordinary spreadsheet, more specialized information management tools can help educators easily make multidimensional queries (asking questions that span several variables, such as grade level, ethnicity, economic status, and test scores) with just a few clicks on a graph.
Histogram is a specialized graph that shows the relative number of occurrences of a particular value or range of values. You can think of the horizontal axis of a histogram as a series of bins that represent the values of the independent variable. The fullness or height of each bin represents the frequency of its occurrence in a data set. Histograms can be helpful in determining whether the results of an assessment are distributed normally or skewed in one direction or another. Histograms can also reveal gaps in performance. For example, imagine a math test in which half of the students in a class were able to demonstrate mastery of dividing fractions and the other half were not. The graph would display this disparity by showing almost half of students' scores on the low end of the grade scale, with the other half distributing on the high end. Bins in the middle would contain few or no scores. This is known as a bimodal distribution and means the low performing group must be retaught.
Pivot table is a spreadsheet or database tool used to display and compare related lists of facts. Pivot tables are especially useful when you want to compare several facts from long lists of data. For example, you could use a pivot table to organize a list of student names with grade level, gender, ethnicity, and SAT-9 score into a summarized form that shows totals for each subgroup. You could then easily compare average scores for eighth-grade girls with eighth-grade boys, or African-American boys versus Hispanic girls.
Transactional data is the day-to-day operational data of an organization that helps it run efficiently. School transactional data, for example, tells us what a student's home address is, what a teacher's highest level of education is, or what a student in sixth grade is averaging in math class. Transactional or operational databases include the student information system, the financial management system, and the library automation system.
< < < Return to Intro
Read other articles from the May Issue
Send a letter to the Editor in response to this article.
|
