Home / DOE / Charts / Pareto of Regression Coefficients / Options

Options¶

This page is the control by control reference for the dialog titled Create Pareto of Regression Coefficients. What the finished chart shows is on Pareto of Regression Coefficients, and how each bar is formed is on Math Details.

Nothing on this panel decides which coefficients appear. The bars are every active term of whichever output level you tick in the Outputs tree. The two boxes below control how many of those bars are drawn and which way round the chart sits, and that is all.

Outputs¶

The left side of the dialog is a box headed Outputs holding a tree with three levels: the worksheet, then each output on it, then each level of that output. Tick the levels you want a chart for. The dialog opens with every level on the active sheet already ticked.

The two upper levels are three-state. Ticking a worksheet or an output ticks everything under it, and clearing it clears everything under it. When only some of the children are ticked, the parent shows a partial state rather than a tick, so the tree tells you at a glance whether a selection is complete.

One worksheet at a time. Ticking anything on a second worksheet silently clears every tick on the one you had selected, and the options on the right rebuild for the new sheet. There is no warning and no way to draw charts from two source sheets in one Create.

If you press Create with nothing ticked, the dialog tells you At least one chart must be selected. and stays open.

This chart is built from a regression sheet only. Design sheets are not offered, because the chart plots a value that only a fitted model can produce.

One Pareto chart per ticked level, and the levels this chart offers are not the same as the ones the other charts offer:

A quantitative output offers Y-Hat and, when the output has a usable standard deviation model, S-Hat.
A binary output offers one line, not two. The other charts of this family offer both the event and the non-event; the Pareto is built with the non-event level suppressed, so only the event appears.
A nominal output offers one line per level except the reference level, which is left out of the tree entirely. The reference level has no coefficients of its own, so there is nothing to draw.

Bars¶

A box headed Bars offers two choices. All terms, selected by default, puts every coefficient of the ticked output level's model on the chart. Top N: is followed by a count box that holds 5 by default and is enabled only when Top N: is chosen; a whole number typed there is meant to limit the chart to that many bars, ranked by the size of the coefficient.

The count box accepts only a whole number; typing anything else marks the box invalid with Must be a whole number, checked when focus leaves the box, and pressing Create with any box on the panel still invalid is refused outright with a message that one or more entries are not a valid number, so an invalid entry never reaches the chart. Once the box holds a valid whole number, a value below 2 (0 or 1) is silently raised to 2. This is where the box stops working as advertised: the chart only actually limits its bar count for a typed value of 3 or higher. A value of 0, 1, or 2 in Top N mode draws every bar, exactly as All terms would, with no warning that the limit did not apply. The box carries no upper limit; a count larger than the number of coefficients available simply draws all of them.

In short: 3 is the smallest count the box honours. A Top N: of 3 or more limits the chart. A Top N: of 0, 1 or 2 draws every bar, exactly as All terms would, and nothing on screen says the limit was ignored. The two-bar Pareto the box appears to offer cannot be produced by any entry.

Layout¶

A box headed Layout offers Vertical or Horizontal, choosing whether the bars run up and down or side to side. Vertical is selected by default.

Turning the chart moves the axis titles with their axes. The term axis is titled Factor and the value axis |Coeff|. The two titles belong to the axes rather than to the edges of the chart, so choosing Horizontal makes the term axis the vertical one and the Factor title travels with it.

Horizontal also reverses the order the terms are plotted in, which is what keeps the ranking reading from the top downwards. Without that reversal the largest bar would sit at the bottom, because a bar chart plots its first category nearest the origin. Vertical needs no such adjustment: its first category is already at the left. Either way the sort itself is unchanged, and the two layouts show the same bars in the same ranking.

While it draws¶

While charts are being written, a status line reports what is happening and a progress bar appears only when more than one chart is being drawn, since a bar for a single chart would sit at 100 percent from the moment it appeared.

Cancel stops the run cleanly between charts, not part way through one. A chart that has already been written stays; the sheet that was mid-write is deleted rather than left half finished. So cancelling never leaves a partial chart behind, but it can leave fewer sheets than you asked for.

Creating with the dialog left open lets you build several charts from one set of options without reopening it. The charts are identical either way: the only difference is whether the window closes afterwards.

When nothing is drawn¶

If the options you chose produce no drawable chart, the dialog reports There are no valid charts selected for the report. and writes nothing. Where the reason is specific, for example an axis rule or a source restriction, that more specific message is shown instead.

A model with no active term other than the constant produces no chart, because the constant is never drawn and there would be nothing left to put on a bar.

The dialog is owned by the Excel window, so Excel cannot cover it while it is open. If it seems to have vanished, it is on another monitor rather than behind the workbook.