fsQCA assumptions about unobserved cases and alternative solutions

Why check the assumptions behind a solution?

A solution can become simpler when it uses assumptions about combinations of conditions that were not observed. Those unobserved combinations are often called logical remainders. Different choices about them can lead to different solutions, even with the same observed data.

The independent calculation checks how those combinations are classified, which smallest sets of terms cover the specified configurations, and how alternative solutions are paired. A term is a combination of conditions in the solution. Checking these steps helps establish whether the final expression follows from the intended assumptions.

Which versions belong to this example?

The table identifies the saved QuickPLS development and installer versions associated with these checks. The independent logical calculation and the later R/QCA attempts are described separately below because they did not produce the same kind of evidence.

On a small screen, swipe the table sideways to see every column.

Working through the possible solutions independently

The reference represents each condition as present, absent or omitted from a term. These patterns are called ternary cubes. It then finds minimum covers: the smallest sets of terms that cover the configurations specified by the example.

A hand-worked two-condition example checks the solution logic. A five-condition example checks classification only. The table lists the conservative and parsimonious alternatives and their pairings. Conservative solutions avoid simplifying with unobserved configurations; parsimonious solutions permit those assumptions more broadly. The larger example checks classification, not a further complete set of solutions.

• Before the 4 November reference attempt, the original review had not run the optional R script for QCA. The later attempt is reported below.
• The original review, before the 4 November reference attempt, did not reconstruct the published fuzzy observations or calculate their fit. The logical examples therefore do not establish agreement on those published membership-based results.

What the alternative counts tell you

The counts show whether the independent calculation finds the expected alternatives and pairs them as intended. This is a check of logical choices and solution structure, rather than a table of decimal estimates with one permitted numerical error.

Read the two examples according to their purposes: the smaller example checks solutions, while the larger one checks classifications. Several properties can be checked within either example; those checks are not separate datasets or studies.

• There is no single allowed decimal difference for these logical and workflow checks. Inspect the expected classifications, alternatives and pairings in the report.

Why the R/QCA attempt on 4 November 2026 is not a completed comparison

The optional R/QCA script stopped before it could complete the comparison. The first attempt failed at an empty-table check. After that check was corrected in a separate copy of the script, QCA stopped with the message "All truth table configurations are used".

The successful independent logical calculation remains a separate result. Neither R/QCA attempt reran QuickPLS, and neither supplies a completed QCA package comparison.

How to inspect the counterfactual test report

The JSON summary covers the two-condition solution check, the five-condition classification check, their alternative counts and the outcome of the later reference attempts. Source documents are identified for each part.

Repeating the work requires the original test inputs, the same assumptions and settings, and the corresponding software versions. The download reports completed work; it does not include the original datasets or app source code.

• Read how logical and numerical checks differ ↗
• Browse checks for other methods ↗