Marketing to consumers is becoming more competitive, complex and fragmented than ever. Nonetheless, entrepreneurs can make highly informed advertising and marketing decisions based on user behavior, and ultimately improve return on investment (ROI), but most businesses leave this valuable information on the table.

The customer conversion journey today may entail a mix of paid and earned media, as well as efforts digital and offline. The only way to know which channels contributed to the customer conversion is through smart measurement.

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Enter attribution.  Attribution is a way of assigning values to marketing channels to determine which contributed to the customer conversion, and where advertising and marketing budgets should be allocated.

For example, say a customer sees your ad on their favorite news site, but doesn’t take action. They later see it on a social network and click the ad, but no conversion occurs. Finally, they see your direct campaign ad on a specific site, click it and the conversion happens. Attribution allows you to track all of this, assign values, pinpoint high-influencing channels and prioritize your marketing strategy.

There are three integral steps for integrating attribution into your marketing campaign.

1. Choose an attribution model: There are a number of attribution models, but among the most commonly used include:

Last click. This assigns full credit to the advertisement that was last clicked. According to a recent survey, 80 percent of advertisers are using this attribution model, though they consider it insufficient. Often, multiple factors contribute to a customer conversion but this model overlooks all of the channels that led the customer down the purchase funnel. They may have seen the ad four times in multiple places, gaining interest each time, but all of the credit would go to that last ad.

First click/first touch point. This model is similar to last click, but in the reverse. It gives full credit to the first clicked ad or first ad displayed to the potential customer, even if it didn’t lead to a conversion right away.

U-shape. This model assigns credit to the first and last touch points. The thought process behind this model is the first ad piqued their interest and the last got them to take action.

Equal. This gives equal credit to each ad or marketing piece the customer viewed. This, however, assumes all ads or marketing efforts are created equal.

Full funnel. This assigns value throughout the different stages of the customer’s journey, revealing powerful insights into the role each ad or marketing piece played. You might assign a certain percentage of the credit to the first ad displayed, a portion to the first ad clicked on, some to the email campaign and, finally, the call-to-action that got them to convert. This allows you to rank the value of each marketing piece and the channel that delivered it.

Test different models to find what works best for your business based on your goals.

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2. Find an attribution platform. Depending on the type of campaign you are running, attribution can be built into the system you are using. If it isn’t, you can use an ad server to introduce it to the campaign. Ad retargeting companies like AdRoll and Perfect Audience have this feature built in, as does Facebook and Google’s DoubleClick Campaign Manager.

For attribution functionality, you can use web analytics platforms such as Google Analytics, IBM Digital Analytics and Adobe Site Catalyst. The other alternative is to hire an attribution specialist to help guide you through the process.

3. A/B testing with attribution is the Holy Grail of customer insights. Attribution combined with A/B testing allows you insights into the channels that are best performing and the ability to test different variables, such as calls to action, value propositions and design, among others. It essentially allows you to understand and optimize how your marketing is impacting the entire sales cycle.

To figure out where your dollars are best spent, integrate attribution into every component of the campaign. That includes social networking ads, retargeting ads, email campaigns, direct campaign ads, etc. The goal is to know “this banner ad, on this site, or this email campaign with this subject line, resulted in X amount of revenue.”

Attribution enables you to better understand your customer’s journey, direct your digital spending accordingly and optimize your media mix.

Related: Tracking Online Consumer Behavior for Improved Marketing Strategies