Array of registered metric types and their arguments

Timeout value, in seconds, for experiment stats cache.

By default, 60 minutes (3600). Updatable via the shrimptest_stats_timeout filter. Also the timeout used to setup the stats-generating WP Cron process.

• usedby: shrimptest_plugin_cron_setup()

Array of registered variant types and their arguments

Delete the specified experiment, if the status will allow.

INDIVIDUAL EXPERIMENT FUNCTIONS

Will delete data not only from the experiments data, but will also delete associated data from other tables.

• return: the number of rows that were deleted
• global: wpdb $wpdb:
• usedby: ShrimpTest_Interface::admin_new_experiment_redirect()

• int $experiment_id
• bool $force

Return a "display-friendly" string of a given metric value, based on the metric that it is.

For example, if the metric is counting currency, the function may take 5 and return '$5'.

• string $metric_name
• float $value
• float $raw

Get an experiment's specification

INDIVIDUAL EXPERIMENT FUNCTIONS
Returns all the data from the experiments table, with the "data" column, if available, unserialized into an array. All associated variants from the experiments_variants table will also be put in the "variants" entry as an array.

• global: wpdb $wpdb:
• usedby: shrimptest_plugin_cron_setup()
• usedby: ShrimpTest_Interface::get_menus()
• uses: ShrimpTest_Model::get_experiment_variants()

• int $experiment_id

Get the computed stats for the specified experiment

INDIVIDUAL EXPERIMENT FUNCTIONS
Will try to pull the stats from the stats cache (which uses the WordPress Transients API), but will recreate it if it has expired or if $force is set.

The return value is organized as follows: for an experiment with X variants, there will be X+2 entries. Entries 0..(X-1) will have statistics for each of the variants. There is also an entry called "total". The variant and total statistics entries are themselves arrays, with the following entries:

• variant_name
• N, the number of participants in the experiment
• avg, the average value of the metric
• sum, the aggregate total value of the metric
• sd, the variance of the metric, in standard deviations

Finally, the return value also has a "stats" entry which contains the following properties:

• unix, human, two representations for the time when this stat was computed
• time, how long this experiment calculation took
• duration_reached, true if the experiment has specified an experiment duration and it has been reached.

If the experiment specification specified an experiment duration, and it has been met with this experiment stats computation, the action shrimptest_experiment_duration_reached will be triggered, and the duration_reached property will be added to the experiment data.

• return: see description for specification
• global: wpdb $wpdb:
• todo: support metric types whose "type" is not "better"
• usedby: shrimptest_plugin_cron_setup()
• usedby: shrimptest_plugin_cron_do_stats()
• uses: ShrimpTest_Model::zscore()
• uses: ShrimpTest_Model::update_experiment()
• uses: ShrimpTest_Model::normal_cdf()

• int $experiment_id
• bool $force

Get a particular experiment variant and its specification

EXPERIMENT VARIANT FUNCTIONS

• global: wpdb $wpdb:
• usedby: ShrimpTest_Variant_Title::swap_title()
• usedby: ShrimpTest_Variant_Shortcode::shortcode_handler()

• int $experiment_id
• int $variant_id

Get an array of metric type objects with some basic metadata, for editing.

Used by the ShrimpTest UI, so metrics which are _programmatic will be disabled, unless they are turned on, for example.

• uses: ShrimpTest_Model::sort_by_defaultness()

• string $current_type

Get an array of variant type objects with some basic metadata, for editing.

Used by the ShrimpTest UI, so variants which are _programmatic will be disabled, unless they are turned on, for example.

• uses: ShrimpTest_Model::sort_by_defaultness()

• string $current_type

Initialization

• global: wpdb $wpdb:
• usedby: ShrimpTest::load_model_and_interface()
• uses:

• ShrimpTest &$shrimptest_instance

Sort by "defaultness"

HELPER FUNCTIONS
A sorting function which will prefer to order objects which have the _default property further forward.

• usedby: ShrimpTest_Model::get_metric_types_to_edit()
• usedby: ShrimpTest_Model::get_variant_types_to_edit()

• object $a
• object $b

Update the specified experiment's status code.

INDIVIDUAL EXPERIMENT FUNCTIONS

Will set the start_time when setting to "active", and the end_time when setting to "finished".

• global: wpdb $wpdb:
• usedby: ShrimpTest_Model::update_experiment()
• usedby: ShrimpTest_Variant_Title::save_postdata()
• usedby: ShrimpTest_Variant_Shortcode::process_detected_shortcode()
• usedby: ShrimpTest_Interface::admin_new_experiment_redirect()

• int $experiment_id
• string $status

Update multiple variants of an experiment

EXPERIMENT VARIANT FUNCTIONS

• global: wpdb $wpdb:
• todo: rewrite this to decrease the number of queries that are called.
• usedby: ShrimpTest_Model::update_experiment()
• usedby: ShrimpTest_Variant_Title::save_postdata()
• uses: ShrimpTest_Model::update_experiment_variant()

• int $experiment_id
• array $variants: variants specifications, keyed by variant id

Update a metric value for the given visitor

• global: wpdb $wpdb:
• todo: validate metric id and/or $value, but note, we've already touched in ShrimpTest::update_visitor_metric()
• usedby: ShrimpTest::update_visitor_metric()

• int $experiment_id
• float $value
• boolean $monotonic: if true, will only update if the value is greater (optional)
• int $visitor_id

Compute a z-score based on the control's stats and the variant's stats

HELPER FUNCTIONS

• usedby: ShrimpTest_Model::get_experiment_stats()

• array $control
• array $variant