River Sampling Versus RDE Sampling: Which is Superior for Market Research

River sampling versus RDE (Random Device Engagement) sampling: it’s a showdown for the ages. As two of the foremost players in survey sampling methods, these two always appear to compete head-to-head for the attention and execution of market researchers.

As prominent players in the survey research sector, both the RDE and river sampling methods are considered superior to using survey panels for market research. 

As the two dominant means of obtaining a survey sample, which forms the core of any market research campaign, it is crucial to be diligent when deliberating over which method to use for your survey sampling.

This article posits river sampling and RDE sampling in a showdown, so that market researchers and general researchers comprehend which is more fitting for their market research needs.

Defining River Sampling

River sampling is an online survey sampling method — the earliest and simplest of its kind. This non-probability sampling method obtains survey respondents by requesting online visitors to take a survey via clicking on a link that routes them to the survey

The link is placed somewhere in a webpage, email or another area in the digital space. Typically, respondents are scouted through web elements such as banners, ads, promotions and offers.

When site or app users click on the link used in river sampling, they are first routed to the screener portion of the survey and if they fit the requirements set in the screener, they are then routed to the questionnaire portion. 

River sampling derives its name from the metaphorical idea that researchers net their study subjects by catching them in the river that is the internet, specifically the flow of traffic in a website. 

Also called intercept sampling and real‐time sampling, this method extracts respondents by engaging them while they take part in some other digital activity

The Two Types of River Sampling

River sampling exists in two forms. While they may appear to be vaguely interchangeable, each form includes a unique method for procuring respondents. In the showdown of river sampling versus RDE sampling, it’s important to understand the workings of each.

Stratified River Sampling

This kind of river sampling involves drawing samples in real-time from online promotions, those that are disseminated through banners, ads, pop-ups and hyperlinks. Market researchers would choose the websites for survey deployment based on statistics on such websites’ traffic. 

Convenience River Sampling

This submethod of river sampling involves the placement of promotions and hyperlinks across websites without previously analyzing the websites’ traffic numbers and types of visitors. As such, market researchers deploy surveys in a completely blind manner. The point of this form of sampling is to derive maximum data at a minimum cost. 

The Pros and Cons of River Sampling

A commonly used method of sampling respondents, river sampling has several advantages and disadvantages. Understanding them is important for researchers, should they consider using this method, or learning how it differs from other sampling methods, such as RDE sampling. 

The Advantages 

  1. Serves as a powerful replacement for survey panels by providing new respondents, those that have not been influenced or conditioned to take part in a survey.
  2. Engages users in their natural digital environments.
  3. Its survey callouts/ links exist in easily noticeable digital properties. 
  4. Creates a faster alternative to the focus group, which involves a group discussion where dominant participants can take charge and make it difficult for more demure participants.
  5. Ensures complete anonymity of respondents.
  6. Exists as a simple method of data gathering, since all researchers need to do is wait for the data to be aggregated.
  7. An inexpensive source of sampling.
  8. A flexible method that collects respondents in the moment, rather than being profiled prior to the survey and recruited manually.

The Disadvantages 

  1. The devices used by potential and opted-in respondents are completely unknown
  2. There is no access to an advertisement’s ID.
  3. Fraudsters can therefore take the same survey twice or more to increase their incentives or the chance to win a prize.
  4. No degree of demographic, geographic or individual targeting is possible.
  5. Banner ads generally have insufficient response rates.
  6. Banners are pushed through ad networks, diminishing the user experience.
  7. Ad-networks optimize their delivery by fighting against random sampling. 
    1. As such, users are picked due to a higher likelihood of responding, from unobserved variables (to the researcher) correlated with how they will respond. At any rate, none of the data is shared, so it is impossible to correct.
  8. It is difficult to reach an acceptable level of representation, as respondents are not tracked. 
  9. Surveyors have no inkling of who will participate in the surveys due to the lack of tracking and profiling. 
  10. This method is prone to receive straight-lining from the respondents. 

Defining RDE Sampling

RDE sampling, also known as Random Device Engagement is an advanced method of non-probability sampling, one that falls in diametrical opposition with survey panels. It is completely random and organic, with no pre-recruitment and no website monitoring.

RDE sampling refers to the sampling practice of engaging online users on all the devices they are already using, be it within advertising networks, mobile apps and other portals on various devices. 

This involves the careful placement of surveys in gaming interfaces and virtual reality, allowing market researchers to offer non-monetary incentives to respondents. These include coins or points in a game, or the ability to win a major virtual in-game prize.

RDE sampling can be disseminated through digital elements similar to the ones used in river sampling, such as banners, ads and other positions on a webpages, such as buttons. These survey callouts e.t. al., must be placed strategically, so that respondents can easily spot them. They must also be created in a way that sparks the curiosity or interest of the webpage’s visitors to click on them in the first place. 

RDE engages potential respondents in their natural digital environments and respondents enter the survey voluntarily. This method also ensures complete randomization, as no pre-recruiting efforts are involved. 

Respondents are also completely anonymous, in terms of their identities, thus, there is no pressure to answer questions in a particular way, such as one that adheres to societal norms and expectations. 

The Key Differences Between River Sampling and RDE Sampling

Many of the traits in RDE sampling render this method to seemingly mimic river sampling, with no apparent distinguishing features. But this is false — there are several ways in which RDE sampling diverges from the river sampling method. 

Unlike river sampling, RDE sampling offers a monitoring functionality, which tracks the unique identifier of respondents’ devices. The survey software that carries out RDE sampling works natively with the device when it is optimized correctly. For example, a strong example of this would be a mobile-first survey platform. 

Furthermore, unlike river sampling, in which respondents are not tracked or identified by demographics, etc., RDE tracks respondents through a unique ID, one that notifies the researchers when the same respondents are changing devices

RDE also relies on artificial intelligence to weed out poor quality responses, such as gibberish answers and users who are on a VPN.  

The Pros and Cons of RDE Sampling

Random Device Engagement sampling carries various benefits and drawbacks that all market researchers should be aware of, even if they do not choose this sampling method. That is because it is critical to weigh these advantages and disadvantages against those of river sampling for a true comparison.

The Advantages 

  1. A higher quality of data due to AI functionality and automatic quality checks.
  2. Respondents are not conditioned through pre recruiting tactics or pressured to answer questions in a certain way due to being in their natural digital environments.
  3. Offers various telemetry data prone to bias correction, involving location history and application usage.
  4. Has a high coverage due to the heavy usage of mobile phones; phones carry a high penetration of about 70% and decent response rates. 
  5. Avoids fraud from SUMAs (single users on multiple accounts); respondents can only answer once and therefore VPN respondents are disqualified.
  6. Tracks different devices that respondents use, important given the uncertainty of the future use of phones.
  7. RDE is fast and cost-effective.
  8. Able to supplement attitudinal data with a vast array of para or telemetry data. 
    1. For example, those who partake in surveys are rather different than those who don’t. As such, it is necessary to get roughly 30 more demographic, attitudinal, and lifestyle questions to understand social trust and how survey respondents are unusual.

The Disadvantages 

  1. Given that this method involves tracking location and application usage, it is not as anonymous.
  2. In reference to Point 1, the researchers will have to add the necessary disclaimers to their surveys.
  3. Surveys on RDE networks may not exist in as diverse a set as they do in river sampling. 
  4. Is still prone to several kinds of survey bias
  5. Does not offer perfect coverage or known probabilities for every respondent.
  6. Respondents may be subject to survey fatigue if the survey is too long and not built with best practices. 

The Verdict of the River Sampling Vs. RDE Sampling Showdown

In conclusion, who comes up victorious in the showdown between river sampling and Random Device Engagement sampling? In the spirit of remaining unbiased, the true victor is up to the market researcher, the business owner, or the marketing department of a business.

This is because each business and operation will envision their market research campaigns differently and thus will have different requirements and standards for their campaigns. This includes how they will execute survey sampling.  

Both methods secure the privacy of respondents, as respondents are never matched with their identities. However, the major point of difference between these two methods is that river sampling does not capture the devices and app usage of the respondents, while RDE does, given that it tracks respondents through unique IDs.

Thus, when using either of these sampling methods, they will have to be dealt with differently. 

In regards to this, market researchers can make the judgment of which sampling method is best. We believe that based on the better data quality and representativeness of the sample, RDE is the superior survey sampling method.

With river sampling, researchers must assess the stability, span and relevance of the promotions used in tandem with the surveys. Additionally, market researchers will need to check security and quota controls during the sampling process. SIngle users participating multiple times must be thwarted with specialized software.

With RDE sampling, the online survey platform must cooperate with the publishers and their networks, so that market researchers can design a native experience with surveys on their platforms. (In river sampling, banner ads are pushed through the ad network instead). Thus, RDE sampling is objectively the stronger sampling method, given that it seamlessly prevents fraud and poor data from its capabilities of tracking down device usage and fending off VPNs, users take part more than once and other nefarious behaviors that mar the data and sample collection process.