ttest_wizard.testRun.runGroupTTests

Description

Runs one explicit t-test for each group after the first, always using the first group as vector A/reference and the later group as vector B. It preserves group order, copies per-comparison labels and observations into canonical result snapshots, and performs no plotting or file IO.

Inputs

groups

Struct vector with scalar text label and numeric-vector values fields. The first element is the reference group. Nonfinite values are reported through the affected runTTest result.

options

Scalar struct with method, alternative, and alpha fields accepted by runTTest. Per-comparison labels are supplied from groups.

Outputs

results

Column struct vector of canonical runTTest results in group order. Element k compares groups(1) minus groups(k+1).

Options

method

Test label from testRun.choices or "welch", "pooled", or "paired". No default is applied; the field is required.

alternative

Alternative label from testRun.choices or "two_sided", "greater", or "less". Direction is reference minus comparison. No default is applied; the field is required.

alpha

Finite numeric scalar strictly between zero and one. No default is applied; the field is required.

Units

Every group must use the same measurement unit. Means, standard deviations, differences, standard errors, and confidence bounds retain that unit. Test statistics, degrees of freedom, and p-values are dimensionless.

Assumptions

Test choice, independence, and pairing remain the caller's scientific responsibility. A paired method pairs each comparison group separately with the first group by displayed row order. No multiple-comparison correction is applied.

Failure Behavior

Fewer than two groups throws ttest_wizard:InsufficientGroups. A malformed group throws ttest_wizard:InvalidGroups. Individual scientific failures are returned through the stable runTTest result statuses.

Errors

ttest_wizard:InsufficientGroups

groups has fewer than two elements.

ttest_wizard:InvalidGroups

A group label is not scalar text or values is not a numeric vector.

ttest_wizard:InvalidTestOptions

options is missing method, alternative, or alpha, or runTTest rejects one of their values.

Example

groups = struct( ...
"label", {"Reference", "Treatment 1", "Treatment 2"}, ...
"values", {[1 2 3], [2 3 4], [1 2 4]});
options = struct("method", "welch", ...
"alternative", "two_sided", "alpha", 0.05);
results = ttest_wizard.testRun.runGroupTTests(groups, options);
assert(numel(results) == 2)