Short Instructions for using ScatterBrainTM with SAT/ACT Data

Recently SAT and ACT data for years 2017 and 2022 were downloaded  for most regular Texas high schools. The data were packaged with my visual display program and put on the website https://polinetworks.com . Following are some step-by-step instructions to enable you to view and interact with that data.  Begin by printing these instructions, do a  <ctrl>/click on  the preceding link, and then perform the following steps:

1.     Click on the last link on the left-hand part of the screen, SAT_ACT.

2.     After reading the Introduction page, click on Item 2.  Display interactive graphs, to the left.

3.     Two graphs will be displayed.  There are 860 high schools represented by the points in each graph.  Each school is represented in both graphs, and are linked to each other, as you will see. In the LH graph,  the vertical axis shows the percentage of students in the schools who achieved a TEA criterion level of performance on the SAT or the ACT (2022). The horizontal axis represents the percentage of FRPL students in the schools.

4.     The graph on the right has the same horizontal axis, but shows a predicted percentage of students in each school who achieved the criterion level, on the vertical axis. As stated in the introduction (Item 1. Introduction to the left) a regression was performed with the percentage of students achieving the criterion level (ABV_CRIT), which was plotted in the left-hand graph, as the dependent variable. Included in the Introduction page is a table of coefficients resulting from the regression, 7 in all. As stated there, the final adjusted r-square is 0.778. (When only FRPL% (ED22) was used as an independent explanatory variable, the adjusted r-square was 0.565.) 

5.     Going back to the graphs, first insert a global regression line in each.  To do this:

a.     Click on [Regr] button;

b.     Make sure both graphs have the linear button on;

c.      Click on the squares for View?  LHG Global and View?  RHG Global.

d.     Click on [Accept].

6.     A feature was recently added to display two different sets of fields in the data window, below the graphs. For this demo, click on the [D1D2} button. It should change to color red, and a different set of field names will appear above the window.

7.     Information about a single point/school can be displayed by drawing a rectangle around it.  A rectangle is formed using the mouse as follows:

a.     Move the cursor near to the point of interest, say above it and to the left, and click the LMB (don’t hold down).

b.     Move the cursor, which will result in a rectangle, by moving the mouse; enclose the point of interest with the rectangle and click the LMB again;

c.      You will see that the enclosed point is now blinking, and data associated with it is displayed in the first row of the data area. If you want to increase the size of the blinking point, click on the [R=1] button. Repeated clicking will increase the size in several discrete steps.

d.     Notice that the selected point is blinking at the position of the selected school in both graphs.

e.     Depressing the LMB once more (with the cursor located in either graph) will terminate the blinking, and will allow you to repeat that process.  If you enclose more than one point in the rectangle, attention will move to successive points after each LMB click.

f.       If you inadvertently enclose more points than you intended, click on the [Clear] button, and start over. In fact, click the [Clear] button now.

8.     The first set of graphs shows 5 outliers up near the 100% value in the LH graph. You could view them as just described, one at a time, or as a group. To view them as a group, do the following:

a.     Click on the [Multi] button, changing it to color red;

b.     Using the mouse to move the cursor as described above, create a rectangle that encloses just those 5 points (click, move, click);

c.      The same 5 points are highlighted in both graphs, and summary data for them is displayed in the data table. The numbers shown are weighted averages, the weights being the enrollments of the schools. Note: these summary statistics only occur if the [Multi] button is “On” or red.

9.     To compare results for groups of schools, do the following:

a.     Click on [Reset], and make sure the [Mult] button is color red.

b.     Move the cursor above and to the left of all points in the LH graph and click the LMB; the cursor should not be to the left of the y-axis vertical line.

c.      Move the cursor down and to the right, enclosing a number of points. As you do this, note that the number in the small gray box near the lower left-hand corner of the graph changes.  The number at any instant is the percentage of all students in the schools enclosed inside the rectangle at that instant. As an exercise, move the cursor down to the x-axis and then move it left or right until it reads approximately 10 percent, then click the LMB again. Data for the schools thus captured are shown in the data window.

d.     Repeat (c), but at the opposite side of the same graph. That is, move the cursor to a point near the upper RH extreme of the same graph, at the maximum value of 100% FRPL. The cursor should not be moved beyond the limit of the vertical axis line. Click the LMB, then move the cursor down near the x-axis and adjust left or right until the percentage in the small box is again near 10 percent, then click the LMB again.

e.     There will now be two rows of data in the data table, one corresponding to each of the 10-percent selections just made. For each row, the PRED_ABV (predicted percentage reaching the SAT/ACT criterion) should be close to ABOV_CRIT (actual value).  The same should be true for the next two columns, which contain actual SAT results and predicted results. These last remarks assume the data fields exhibited correspond to the [D1D2] button being in its red state. There are obviously very large differences in the test score results between the two groups chosen.  The group at the left should have had approximately 12 pct FRPL (ED%) students, the second group about 93 percent.

f.       Any sets of schools can be compared to one another, using the procedure just described.

10.  Clicking on either the [LHG] or [RHG] buttons will change the graphs being displayed on either side.  The third graph, which shows the schools plotted on a state map with the Educational Service Center (ESC) regions drawn in, only works properly on the left-hand side. In clicking/rotating among the 8 different graphs, the last one, with G8 in its title line, is intriguing.  One would think there would be a pretty stable relationship between the SAT scores (horizontal axis) and the SAT/ACT meets criterion percentage, plotted on the vertical axis.  If you switch the [Multi] function off (not red) and use the mouse-drawn rectangles to identify some of those schools which seem to be outliers, in virtually all cases their SAT scores exceed predictions, but the SAT/ACT meets criterion percentages vary somewhat in that regard.

11.  Another feature allows you to select just those schools in a specific district

a.     Restore the display to its original state by clicking on the item 2. Display interactive graphs to the left. Note that the [D1D2] button has reverted to color white, indicating the data fields shown have been changed back to the original ones.

b.     Select the [Hlt/Sel] button, making it color red.

c.      Click on the popup list labelled District, and select/click on a large district, such as Austin ISD. Only the high schools in Austin should now be displayed.

d.     De-select the [Hlt/Sel] function, making it color white. It should only be set (red) when a district or a county is being selected. Also, click on [Clear].

e.     The two mouse identification functions described above will work with this reduced set.  If the [Multi] function is used (i.e., if it is red) the percentages shown as you vary the size of the encompassing rectangle will now only refer to the selected subset of schools’ enrollments.

f.       The [Hlt/Sel] feature can also be used with counties.  If it is on/red, selecting a county from the County pop-up list will select the districts in that county, and will put the districts’ names into the District pop-up list, from which they can be used as described previously  

12.  A final feature pointed to is the [Lists] function.  The program/webpage  already includes two lists of districts. One has the name D16, 16 of the larger districts, the other has the name BIG100, 100 of the largest school districts. To use either of these, do the following;

a.     Click the [Reset] button, then Click on the [Lists] button.

b.     Click on the [Select List] button on the page that pops up.

c.      Select either D16 or BIG100. The district names included in the selected list should appear in the left-hand panel.

d.     Click on the button named [SelectDistricts].

e.     If the [Hlt/Sel] button is turned off (white) selecting one of the district names that was written to the District popup select list will highlight the schools in that district.  If the [Hlt/Sel] button is turned on (red), selecting one of the district names that were written to the district popup list will in turn select and display only those schools in that selected district. However, other districts and their schools can be selected from the district names’ popup list.  If the [Hlt/Sel] button is off/white when a district is selected from the district list, the schools in that district are merely highlighted in a distinct color, but the other schools are not deselected.

f.       Clicking on the [Reset] button re-selects all districts and schools.

g.     Last hint; having clicked on the [List] button, thereby displaying the double-paned edit page, if you then use the mouse to select a district name from the Dname popup list, that name will be written to the left-hand area, titled “Create external lists:” Selecting additional names from the list of district names will add them to the list area.  If you then type in a name for the new list you have just created, in the box just to the right of the [Save] button, and then click on the [Save] button, the list will be saved to what is called local storage on your computer. The next time you go to this list edit page, and click on [Select List], the name of your newly-created list will appear in the drop-down menu where it can be selected. Only the schools contained in the districts in your custom list will then be available for interacting with, until the [Reset] button is clicked. This feature is useful if the user intends to focus on a specific set of districts for some reason.

13.  There is an option named [Instructions] available at the right-most side of the buttons lined up at the bottom of the display. Those instructions are still fairly accurate, although they were written specifically for an earlier version of the software and data set (see list on Home page).