This script is based on my previous Ad Testing Script but has some additional features. Namely, instead of pausing stats based purely on a metric, this script calculates the statistical significance of the test before making a decision. The calculations are based on a blog post and spreadsheet from VisualWebsiteOptimizer that I modified to work with AdWords Ads.
I also incorporated the ability to link directly to the Campaign or AdGroup from the notification email which I posted about before. All you need to do is fill in the __c and __u parameters to enable that feature.
And finally, since this is probably the largest and most complicated script I've shared here, I used the logic from my post about Google Analytics reporting to fire a beacon whenever the script is ran. You are more than welcome to disable it (remove beacon(); from the second to the last line of the main function), but I would love to get an idea of just how many people are using this script.
Since this script is pretty big, and the formatting here can be a little iffy sometimes, you can also download it from GitHub.
Thanks as always for reading and have a fun and safe holiday.
Thanks,
Russ
/*********************************************
* Automated Creative Testing With Statistical Significance
* Version 2.1
* Changelog v2.1
* - Fixed INVALID_PREDICATE_ENUM_VALUE
* Changelog v2.0
* - Fixed bug in setting the correct date
* - Script now uses a minimum visitors threshold
* per Ad instead of AdGroup
* - Added the ability to add the start date as a label to AdGroups
* - Added ability to check mobile and desktop ads separately
* Changelog v1.1.1 - Fixed bug with getDisplayUrl
* Changelog v1.1
* - Added ability to only run on some campaigns
* - Fixed bug in info logging
* Russ Savage
* FreeAdWordsScripts.com
**********************************************/
var EXTRA_LOGS = true;
var TO = ['user@email.com'];
var CONFIDENCE_LEVEL = 95; // 90%, 95%, or 99% are most common
//If you only want to run on some campaigns, apply a label to them
//and put the name of the label here. Leave blank to run on all campaigns.
var CAMPAIGN_LABEL = '';
//These two metrics are the components that make up the metric you
//want to compare. For example, this measures CTR = Clicks/Impressions
//Other examples might be:
// Cost Per Conv = Cost/Conversions
// Conversion Rate = Conversions/Clicks
// Cost Per Click = Cost/Clicks
var VISITORS_METRIC = 'Impressions';
var CONVERSIONS_METRIC = 'Clicks';
//This is the number of impressions the Ad needs to have in order
//to start measuring the results of a test.
var VISITORS_THRESHOLD = 100;
//Setting this to true to enable the script to check mobile ads
//against other mobile ads only. Enabling this will start new tests
//in all your AdGroups so only enable this after you have completed
//a testing cycle.
var ENABLE_MOBILE_AD_TESTING = false;
//Set this on the first run which should be the approximate last time
//you started a new creative test. After the first run, this setting
//will be ignored.
var OVERRIDE_LAST_TOUCHED_DATE = 'Jan 1, 2014';
var LOSER_LABEL = 'Loser '+CONFIDENCE_LEVEL+'% Confidence';
var CHAMPION_LABEL = 'Current Champion';
// Set this to true and the script will apply a label to
// each AdGroup to let you know the date the test started
// This helps you validate the results of the script.
var APPLY_TEST_START_DATE_LABELS = true;
//These come from the url when you are logged into AdWords
//Set these if you want your emails to link directly to the AdGroup
var __c = '';
var __u = '';
function main() {
createLabelIfNeeded(LOSER_LABEL,"#FF00FF"); //Set the colors of the labels here
createLabelIfNeeded(CHAMPION_LABEL,"#0000FF"); //Set the colors of the labels here
//Let's find all the AdGroups that have new tests starting
var currentAdMap = getCurrentAdsSnapshot();
var previousAdMap = getPreviousAdsSnapshot();
if(previousAdMap) {
currentAdMap = updateCurrentAdMap(currentAdMap,previousAdMap);
}
storeAdsSnapshot(currentAdMap);
previousAdMap = null;
//Now run through the AdGroups to find tests
var agSelector = AdWordsApp.adGroups()
.withCondition('CampaignStatus = ENABLED')
.withCondition('AdGroupStatus = ENABLED')
.withCondition('Status = ENABLED');
if(CAMPAIGN_LABEL !== '') {
var campNames = getCampaignNames();
agSelector = agSelector.withCondition("CampaignName IN ['"+campNames.join("','")+"']");
}
var agIter = agSelector.get();
var todayDate = getDateString(new Date(),'yyyyMMdd');
var touchedAdGroups = [];
var finishedEarly = false;
while(agIter.hasNext()) {
var ag = agIter.next();
var numLoops = (ENABLE_MOBILE_AD_TESTING) ? 2 : 1;
for(var loopNum = 0; loopNum < numLoops; loopNum++) {
var isMobile = (loopNum == 1);
var rowKey;
if(isMobile) {
info('Checking Mobile Ads in AdGroup: "'+ag.getName()+'"');
rowKey = [ag.getCampaign().getId(),ag.getId(),'Mobile'].join('-');
} else {
info('Checking Ads in AdGroup: "'+ag.getName()+'"');
rowKey = [ag.getCampaign().getId(),ag.getId()].join('-');
}
if(!currentAdMap[rowKey]) { //This shouldn't happen
warn('Could not find AdGroup: '+ag.getName()+' in current ad map.');
continue;
}
if(APPLY_TEST_START_DATE_LABELS) {
var dateLabel;
if(isMobile) {
dateLabel = 'Mobile Tests Started: '+getDateString(currentAdMap[rowKey].lastTouched,'yyyy-MM-dd');
} else {
dateLabel = 'Tests Started: '+getDateString(currentAdMap[rowKey].lastTouched,'yyyy-MM-dd');
}
createLabelIfNeeded(dateLabel,"#8A2BE2");
//remove old start date
var labelIter = ag.labels().withCondition("Name STARTS_WITH '"+dateLabel.split(':')[0]+"'")
.withCondition("Name != '"+dateLabel+"'").get();
while(labelIter.hasNext()) {
var label = labelIter.next();
ag.removeLabel(label.getName());
if(!label.adGroups().get().hasNext()) {
//if there are no more entities with that label, delete it.
label.remove();
}
}
applyLabel(ag,dateLabel);
}
//Here is the date range for the test metrics
var lastTouchedDate = getDateString(currentAdMap[rowKey].lastTouched,'yyyyMMdd');
info('Last Touched Date: '+lastTouchedDate+' Todays Date: '+ todayDate);
if(lastTouchedDate === todayDate) {
//Special case where the AdGroup was updated today which means a new test has started.
//Remove the old labels, but keep the champion as the control for the next test
info('New test is starting in AdGroup: '+ag.getName());
removeLoserLabelsFromAds(ag,isMobile);
continue;
}
//Is there a previous winner? if so we should use it as the control.
var controlAd = checkForPreviousWinner(ag,isMobile);
//Here we order by the Visitors metric and use that as a control if we don't have one
var adSelector = ag.ads().withCondition('Status = ENABLED').withCondition('AdType = TEXT_AD');
if(!AdWordsApp.getExecutionInfo().isPreview()) {
adSelector = adSelector.withCondition("LabelNames CONTAINS_NONE ['"+[LOSER_LABEL,CHAMPION_LABEL].join("','")+"']");
}
var adIter = adSelector.forDateRange(lastTouchedDate, todayDate)
.orderBy(VISITORS_METRIC+" DESC")
.get();
if( (controlAd == null && adIter.totalNumEntities() < 2) ||
(controlAd != null && adIter.totalNumEntities() < 1) )
{
info('AdGroup did not have enough eligible Ads. Had: '+adIter.totalNumEntities()+', Needed at least 2');
continue;
}
if(!controlAd) {
info('No control set for AdGroup. Setting one.');
while(adIter.hasNext()) {
var ad = adIter.next();
if(shouldSkip(isMobile,ad)) { continue; }
controlAd = ad;
break;
}
if(!controlAd) {
continue;
}
applyLabel(controlAd,CHAMPION_LABEL);
}
while(adIter.hasNext()) {
var testAd = adIter.next();
if(shouldSkip(isMobile,testAd)) { continue; }
//The Test object does all the heavy lifting for us.
var test = new Test(controlAd,testAd,
CONFIDENCE_LEVEL,
lastTouchedDate,todayDate,
VISITORS_METRIC,CONVERSIONS_METRIC);
info('Control - Visitors: '+test.getControlVisitors()+' Conversions: '+test.getControlConversions());
info('Test - Visitors: '+test.getTestVisitors()+' Conversions: '+test.getTestConversions());
info('P-Value: '+test.getPValue());
if(test.getControlVisitors() < VISITORS_THRESHOLD ||
test.getTestVisitors() < VISITORS_THRESHOLD)
{
info('Not enough visitors in the control or test ad. Skipping.');
continue;
}
//Check for significance
if(test.isSignificant()) {
var loser = test.getLoser();
removeLabel(loser,CHAMPION_LABEL); //Champion has been dethroned
applyLabel(loser,LOSER_LABEL);
//The winner is the new control. Could be the same as the old one.
controlAd = test.getWinner();
applyLabel(controlAd,CHAMPION_LABEL);
//We store some metrics for a nice email later
if(!ag['touchCount']) {
ag['touchCount'] = 0;
touchedAdGroups.push(ag);
}
ag['touchCount']++;
}
}
//Let's bail if we run out of time so we can send the emails.
if((!AdWordsApp.getExecutionInfo().isPreview() && AdWordsApp.getExecutionInfo().getRemainingTime() < 60) ||
( AdWordsApp.getExecutionInfo().isPreview() && AdWordsApp.getExecutionInfo().getRemainingTime() < 10) )
{
finishedEarly = true;
break;
}
}
}
if(touchedAdGroups.length > 0) {
sendMailForTouchedAdGroups(touchedAdGroups,finishedEarly);
}
beacon();
}
// A helper function to return the list of campaign ids with a label for filtering
function getCampaignNames() {
var campNames = [];
var labelIter = AdWordsApp.labels().withCondition("Name = '"+CAMPAIGN_LABEL+"'").get();
if(labelIter.hasNext()) {
var label = labelIter.next();
var campIter = label.campaigns().get();
while(campIter.hasNext()) {
campNames.push(campIter.next().getName());
}
}
return campNames;
}
function applyLabel(entity,label) {
if(!AdWordsApp.getExecutionInfo().isPreview()) {
entity.applyLabel(label);
} else {
var adText = (entity.getEntityType() === 'Ad') ? [entity.getHeadline(),entity.getDescription1(),
entity.getDescription2(),entity.getDisplayUrl()].join(' ')
: entity.getName();
Logger.log('PREVIEW: Would have applied label: '+label+' to Entity: '+ adText);
}
}
function removeLabel(ad,label) {
if(!AdWordsApp.getExecutionInfo().isPreview()) {
ad.removeLabel(label);
} else {
var adText = [ad.getHeadline(),ad.getDescription1(),ad.getDescription2(),ad.getDisplayUrl()].join(' ');
Logger.log('PREVIEW: Would have removed label: '+label+' from Ad: '+ adText);
}
}
// This function checks if the AdGroup has an Ad with a Champion Label
// If so, the new test should use that as the control.
function checkForPreviousWinner(ag,isMobile) {
var adSelector = ag.ads().withCondition('Status = ENABLED')
.withCondition('AdType = TEXT_AD');
if(!AdWordsApp.getExecutionInfo().isPreview()) {
adSelector = adSelector.withCondition("LabelNames CONTAINS_ANY ['"+CHAMPION_LABEL+"']");
}
var adIter = adSelector.get();
while(adIter.hasNext()) {
var ad = adIter.next();
if(shouldSkip(isMobile,ad)) { continue; }
info('Found a previous winner. Using it as the control.');
return ad;
}
return null;
}
function shouldSkip(isMobile,ad) {
if(isMobile) {
if(!ad.isMobilePreferred()) {
return true;
}
} else {
if(ad.isMobilePreferred()) {
return true;
}
}
return false;
}
// This function sends the email to the people in the TO array.
// If the script finishes early, it adds a notice to the email.
function sendMailForTouchedAdGroups(ags,finishedEarly) {
var htmlBody = '<html><head></head><body>';
if(finishedEarly) {
htmlBody += 'The script was not able to check all AdGroups. ' +
'It will check additional AdGroups on the next run.<br / >' ;
}
htmlBody += 'The following AdGroups have one or more creative tests that have finished.' ;
htmlBody += buildHtmlTable(ags);
htmlBody += '<p><small>Generated by <a href="http://www.freeadwordsscripts.com">FreeAdWordsScripts.com</a></small></p>' ;
htmlBody += '</body></html>';
var options = {
htmlBody : htmlBody,
};
var subject = ags.length + ' Creative Test(s) Completed - ' +
Utilities.formatDate(new Date(), AdWordsApp.currentAccount().getTimeZone(), 'yyyy-MM-dd');
for(var i in TO) {
MailApp.sendEmail(TO[i], subject, ags.length+' AdGroup(s) have creative tests that have finished.', options);
}
}
// This function uses my HTMLTable object to build the styled html table for the email.
function buildHtmlTable(ags) {
var table = new HTMLTable();
//CSS from: http://coding.smashingmagazine.com/2008/08/13/top-10-css-table-designs/
//Inlined using: http://inlinestyler.torchboxapps.com/
table.setTableStyle(['font-family: "Lucida Sans Unicode","Lucida Grande",Sans-Serif;',
'font-size: 12px;',
'background: #fff;',
'margin: 45px;',
'width: 480px;',
'border-collapse: collapse;',
'text-align: left'].join(''));
table.setHeaderStyle(['font-size: 14px;',
'font-weight: normal;',
'color: #039;',
'padding: 10px 8px;',
'border-bottom: 2px solid #6678b1'].join(''));
table.setCellStyle(['border-bottom: 1px solid #ccc;',
'padding: 4px 6px'].join(''));
table.addHeaderColumn('#');
table.addHeaderColumn('Campaign Name');
table.addHeaderColumn('AdGroup Name');
table.addHeaderColumn('Tests Completed');
for(var i in ags) {
table.newRow();
table.addCell(table.getRowCount());
var campName = ags[i].getCampaign().getName();
var name = ags[i].getName();
var touchCount = ags[i]['touchCount'];
var campLink, agLink;
if(__c !== '' && __u !== '') { // You should really set these.
campLink = getUrl(ags[i].getCampaign(),'Ad groups');
agLink = getUrl(ags[i],'Ads');
table.addCell(a(campLink,campName));
table.addCell(a(agLink,name));
} else {
table.addCell(campName);
table.addCell(name);
}
table.addCell(touchCount,'text-align: right');
}
return table.toString();
}
// Just a helper to build the html for a link.
function a(link,val) {
return '<a href="'+link+'">'+val+'</a>';
}
// This function finds all the previous losers and removes their label.
// It is used when the script detects a change in the AdGroup and needs to
// start a new test.
function removeLoserLabelsFromAds(ag,isMobile) {
var adSelector = ag.ads().withCondition('Status = ENABLED');
if(!AdWordsApp.getExecutionInfo().isPreview()) {
adSelector = adSelector.withCondition("LabelNames CONTAINS_ANY ['"+LOSER_LABEL+"']");
}
var adIter = adSelector.get();
while(adIter.hasNext()) {
var ad = adIter.next();
if(shouldSkip(isMobile,ad)) { continue; }
removeLabel(ad,LOSER_LABEL);
}
}
// A helper function to create a new label if it doesn't exist in the account.
function createLabelIfNeeded(name,color) {
if(!AdWordsApp.labels().withCondition("Name = '"+name+"'").get().hasNext()) {
info('Creating label: "'+name+'"');
AdWordsApp.createLabel(name,"",color);
} else {
info('Label: "'+name+'" already exists.');
}
}
// This function compares the previous and current Ad maps and
// updates the current map with the date that the AdGroup was last touched.
// If OVERRIDE_LAST_TOUCHED_DATE is set and there is no previous data for the
// AdGroup, it uses that as the last touched date.
function updateCurrentAdMap(current,previous) {
info('Updating the current Ads map using historical snapshot.');
for(var rowKey in current) {
var currentAds = current[rowKey].adIds;
var previousAds = (previous[rowKey]) ? previous[rowKey].adIds : [];
if(currentAds.join('-') === previousAds.join('-')) {
current[rowKey].lastTouched = previous[rowKey].lastTouched;
}
if(previousAds.length === 0 && OVERRIDE_LAST_TOUCHED_DATE !== '') {
current[rowKey].lastTouched = new Date(OVERRIDE_LAST_TOUCHED_DATE);
}
//if we make it here without going into the above if statements
//then the adgroup has changed and we should keep the new date
}
info('Finished updating the current Ad map.');
return current;
}
// This stores the Ad map snapshot to a file so it can be used for the next run.
// The data is stored as a JSON string for easy reading later.
function storeAdsSnapshot(data) {
info('Storing the Ads snapshot to Google Drive.');
var fileName = getSnapshotFilename();
var file = DriveApp.getFilesByName(fileName).next();
file.setContent(Utilities.jsonStringify(data));
info('Finished.');
}
// This reads the JSON formatted previous snapshot from a file on GDrive
// If the file doesn't exist, it creates a new one and returns an empty map.
function getPreviousAdsSnapshot() {
info('Loading the previous Ads snapshot from Google Drive.');
var fileName = getSnapshotFilename();
var fileIter = DriveApp.getFilesByName(fileName);
if(fileIter.hasNext()) {
return Utilities.jsonParse(fileIter.next().getBlob().getDataAsString());
} else {
DriveApp.createFile(fileName, '');
return {};
}
}
// A helper function to build the filename for the snapshot.
function getSnapshotFilename() {
var accountId = AdWordsApp.currentAccount().getCustomerId();
return (accountId + ' Ad Testing Script Snapshot.json');
}
// This function pulls the Ad Performance Report which is the fastest
// way to build a snapshot of the current ads in the account.
// This only pulls in active text ads.
function getCurrentAdsSnapshot() {
info('Running Ad Performance Report to get current Ads snapshot.');
var OPTIONS = { includeZeroImpressions : true };
var cols = ['CampaignId','AdGroupId','Id','DevicePreference','Impressions'];
var report = 'AD_PERFORMANCE_REPORT';
var query = ['select',cols.join(','),'from',report,
'where AdType = TEXT_AD',
'and AdNetworkType1 = SEARCH',
'and CampaignStatus = ENABLED',
'and AdGroupStatus = ENABLED',
'and Status = ENABLED',
'during','TODAY'].join(' ');
var results = {}; // { campId-agId : row, ... }
var reportIter = AdWordsApp.report(query, OPTIONS).rows();
while(reportIter.hasNext()) {
var row = reportIter.next();
var rowKey = [row.CampaignId,row.AdGroupId].join('-');
if(ENABLE_MOBILE_AD_TESTING && row.DevicePreference == 30001) {
rowKey += '-Mobile';
}
if(!results[rowKey]) {
results[rowKey] = { adIds : [], lastTouched : new Date() };
}
results[rowKey].adIds.push(row.Id);
}
for(var i in results) {
results[i].adIds.sort();
}
info('Finished building the current Ad map.');
return results;
}
//Helper function to format the date
function getDateString(date,format) {
return Utilities.formatDate(new Date(date),AdWordsApp.currentAccount().getTimeZone(),format);
}
// Function to build out the urls for deeplinking into the AdWords account.
// For this to work, you need to have __c and __u filled in.
// Taken from: http://www.freeadwordsscripts.com/2013/11/building-entity-deep-links-with-adwords.html
function getUrl(entity,tab) {
var customerId = __c;
var effectiveUserId = __u;
var decodedTab = getTab(tab);
var base = 'https://adwords.google.com/cm/CampaignMgmt?';
var url = base+'__c='+customerId+'&__u='+effectiveUserId+'#';
if(typeof entity['getEntityType'] === 'undefined') {
return url+'r.ONLINE.di&app=cm';
}
var type = entity.getEntityType()
if(type === 'Campaign') {
return url+'c.'+entity.getId()+'.'+decodedTab+'&app=cm';
}
if(type === 'AdGroup') {
return url+'a.'+entity.getId()+'_'+entity.getCampaign().getId()+'.'+decodedTab+'&app=cm';
}
if(type === 'Keyword') {
return url+'a.'+entity.getAdGroup().getId()+'_'+entity.getCampaign().getId()+'.key&app=cm';
}
if(type === 'Ad') {
return url+'a.'+entity.getAdGroup().getId()+'_'+entity.getCampaign().getId()+'.create&app=cm';
}
return url+'r.ONLINE.di&app=cm';
function getTab(tab) {
var mapping = {
'Ad groups':'ag','Settings:All settings':'st_sum',
'Settings:Locations':'st_loc','Settings:Ad schedule':'st_as',
'Settings:Devices':'st_p','Ads':'create',
'Keywords':'key','Audiences':'au','Ad extensions':'ae',
'Auto targets':'at','Dimensions' : 'di'
};
if(mapping[tab]) { return mapping[tab]; }
return 'key'; //default to keyword tab
}
}
// Helper function to print info logs
function info(msg) {
if(EXTRA_LOGS) {
Logger.log('INFO: '+msg);
}
}
// Helper function to print more serious warnings
function warn(msg) {
Logger.log('WARNING: '+msg);
}
/********************************
* Track Script Runs in Google Analytics
* Created By: Russ Savage
* FreeAdWordsScripts.com
********************************/
function beacon() {
var TAG_ID = 'UA-40187672-2';
var CAMPAIGN_SOURCE = 'adwords';
var CAMPAIGN_MEDIUM = 'scripts';
var CAMPAIGN_NAME = 'AdTestingScriptV2_1';
var HOSTNAME = 'www.freeadwordsscripts.com';
var PAGE = '/Ad_Testing_Script_v2_1';
if(AdWordsApp.getExecutionInfo().isPreview()) {
PAGE += '/preview';
}
var DOMAIN_LINK = 'http://'+HOSTNAME+PAGE;
//Pulled from: http://stackoverflow.com/questions/105034/how-to-create-a-guid-uuid-in-javascript
var uuid = 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g,
function(c) {var r = Math.random()*16|0,v=c=='x'?r:r&0x3|0x8;return v.toString(16);});
var url = 'http://www.google-analytics.com/collect?';
var payload = {
'v':1,'tid':TAG_ID,'cid':uuid,
't':'pageview','cs':CAMPAIGN_SOURCE,'cm':CAMPAIGN_MEDIUM,'cn':CAMPAIGN_NAME,
'dl':DOMAIN_LINK
};
var qs = '';
for(var key in payload) {
qs += key + '=' + encodeURIComponent(payload[key]) + '&';
}
url += qs.substring(0,qs.length-1);
UrlFetchApp.fetch(url);
}
/*********************************************
* Test: A class for runnning A/B Tests for Ads
* Version 1.0
* Based on VisualWebsiteOptimizer logic: http://goo.gl/jiImn
* Russ Savage
* FreeAdWordsScripts.com
**********************************************/
// A description of the parameters:
// control - the control Ad, test - the test Ad
// startDate, endDate - the start and end dates for the test
// visitorMetric, conversionMetric - the components of the metric to use for the test
function Test(control,test,desiredConf,startDate,endDate,visitorMetric,conversionMetric) {
this.desiredConfidence = desiredConf/100;
this.verMetric = visitorMetric;
this.conMetric = conversionMetric;
this.startDate = startDate;
this.endDate = endDate;
this.winner;
this.controlAd = control;
this.controlStats = (this.controlAd['stats']) ? this.controlAd['stats'] : this.controlAd.getStatsFor(this.startDate, this.endDate);
this.controlAd['stats'] = this.controlStats;
this.controlVisitors = this.controlStats['get'+this.verMetric]();
this.controlConversions = this.controlStats['get'+this.conMetric]();
this.controlCR = getConversionRate(this.controlVisitors,this.controlConversions);
this.testAd = test;
this.testStats = (this.testAd['stats']) ? this.testAd['stats'] : this.testAd.getStatsFor(this.startDate, this.endDate);
this.testAd['stats'] = this.testStats;
this.testVisitors = this.testStats['get'+this.verMetric]();
this.testConversions = this.testStats['get'+this.conMetric]();
this.testCR = getConversionRate(this.testVisitors,this.testConversions);
this.pValue;
this.getControlVisitors = function() { return this.controlVisitors; }
this.getControlConversions = function() { return this.controlConversions; }
this.getTestVisitors = function() { return this.testVisitors; }
this.getTestConversions = function() { return this.testConversions; }
// Returns the P-Value for the two Ads
this.getPValue = function() {
if(!this.pValue) {
this.pValue = calculatePValue(this);
}
return this.pValue;
};
// Determines if the test has hit significance
this.isSignificant = function() {
var pValue = this.getPValue();
if(pValue && pValue !== 'N/A' && (pValue >= this.desiredConfidence || pValue <= (1 - this.desiredConfidence))) {
return true;
}
return false;
}
// Returns the winning Ad
this.getWinner = function() {
if(this.decideWinner() === 'control') {
return this.controlAd;
}
if(this.decideWinner() === 'challenger') {
return this.testAd;
}
return null;
};
// Returns the losing Ad
this.getLoser = function() {
if(this.decideWinner() === 'control') {
return this.testAd;
}
if(this.decideWinner() === 'challenger') {
return this.controlAd;
}
return null;
};
// Determines if the control or the challenger won
this.decideWinner = function () {
if(this.winner) {
return this.winner;
}
if(this.isSignificant()) {
if(this.controlCR >= this.testCR) {
this.winner = 'control';
} else {
this.winner = 'challenger';
}
} else {
this.winner = 'no winner';
}
return this.winner;
}
// This function returns the confidence level for the test
function calculatePValue(instance) {
var control = {
visitors: instance.controlVisitors,
conversions: instance.controlConversions,
cr: instance.controlCR
};
var challenger = {
visitors: instance.testVisitors,
conversions: instance.testConversions,
cr: instance.testCR
};
var z = getZScore(control,challenger);
if(z == -1) { return 'N/A'; }
var norm = normSDist(z);
return norm;
}
// A helper function to make rounding a little easier
function round(value) {
var decimals = Math.pow(10,5);
return Math.round(value*decimals)/decimals;
}
// Return the conversion rate for the test
function getConversionRate(visitors,conversions) {
if(visitors == 0) {
return -1;
}
return conversions/visitors;
}
function getStandardError(cr,visitors) {
if(visitors == 0) {
throw 'Visitors cannot be 0.';
}
return Math.sqrt((cr*(1-cr)/visitors));
}
function getZScore(c,t) {
try {
if(!c['se']) { c['se'] = getStandardError(c.cr,c.visitors); }
if(!t['se']) { t['se'] = getStandardError(t.cr,t.visitors); }
} catch(e) {
Logger.log(e);
return -1;
}
if((Math.sqrt(Math.pow(c.se,2)+Math.pow(t.se,2))) == 0) {
Logger.log('WARNING: Somehow the denominator in the Z-Score calulator was 0.');
return -1;
}
return ((c.cr-t.cr)/Math.sqrt(Math.pow(c.se,2)+Math.pow(t.se,2)));
}
//From: http://www.codeproject.com/Articles/408214/Excel-Function-NORMSDIST-z
function normSDist(z) {
var sign = 1.0;
if (z < 0) { sign = -1; }
return round(0.5 * (1.0 + sign * erf(Math.abs(z)/Math.sqrt(2))));
}
// From: http://picomath.org/javascript/erf.js.html
function erf(x) {
// constants
var a1 = 0.254829592;
var a2 = -0.284496736;
var a3 = 1.421413741;
var a4 = -1.453152027;
var a5 = 1.061405429;
var p = 0.3275911;
// Save the sign of x
var sign = 1;
if (x < 0) {
sign = -1;
}
x = Math.abs(x);
// A&S formula 7.1.26
var t = 1.0/(1.0 + p*x);
var y = 1.0 - (((((a5*t + a4)*t) + a3)*t + a2)*t + a1)*t*Math.exp(-x*x);
return sign*y;
}
}
/*********************************************
* HTMLTable: A class for building HTML Tables
* Version 1.0
* Russ Savage
* FreeAdWordsScripts.com
**********************************************/
function HTMLTable() {
this.headers = [];
this.columnStyle = {};
this.body = [];
this.currentRow = 0;
this.tableStyle;
this.headerStyle;
this.cellStyle;
this.addHeaderColumn = function(text) {
this.headers.push(text);
};
this.addCell = function(text,style) {
if(!this.body[this.currentRow]) {
this.body[this.currentRow] = [];
}
this.body[this.currentRow].push({ val:text, style:(style) ? style : '' });
};
this.newRow = function() {
if(this.body != []) {
this.currentRow++;
}
};
this.getRowCount = function() {
return this.currentRow;
};
this.setTableStyle = function(css) {
this.tableStyle = css;
};
this.setHeaderStyle = function(css) {
this.headerStyle = css;
};
this.setCellStyle = function(css) {
this.cellStyle = css;
if(css[css.length-1] !== ';') {
this.cellStyle += ';';
}
};
this.toString = function() {
var retVal = '<table ';
if(this.tableStyle) {
retVal += 'style="'+this.tableStyle+'"';
}
retVal += '>'+_getTableHead(this)+_getTableBody(this)+'</table>';
return retVal;
};
function _getTableHead(instance) {
var headerRow = '';
for(var i in instance.headers) {
headerRow += _th(instance,instance.headers[i]);
}
return '<thead><tr>'+headerRow+'</tr></thead>';
};
function _getTableBody(instance) {
var retVal = '<tbody>';
for(var r in instance.body) {
var rowHtml = '<tr>';
for(var c in instance.body[r]) {
rowHtml += _td(instance,instance.body[r][c]);
}
rowHtml += '</tr>';
retVal += rowHtml;
}
retVal += '</tbody>';
return retVal;
};
function _th(instance,val) {
var retVal = '<th scope="col" ';
if(instance.headerStyle) {
retVal += 'style="'+instance.headerStyle+'"';
}
retVal += '>'+val+'</th>';
return retVal;
};
function _td(instance,cell) {
var retVal = '<td ';
if(instance.cellStyle || cell.style) {
retVal += 'style="';
if(instance.cellStyle) {
retVal += instance.cellStyle;
}
if(cell.style) {
retVal += cell.style;
}
retVal += '"';
}
retVal += '>'+cell.val+'</td>';
return retVal;
};
}