### Are Call Limits Adaptive?

In the same vein as previous posts, I'm continuing to think about current practices that might be recast as adaptive.

Call limits are a fairly common practice. But they are also, at least for projects that I have worked on, notoriously difficult to implement. For example, it may happen that when project targets for numbers of interviews are not being met, then these limits will be violated.

We might even argue that since the timing of the calls is not always well regulated, that it is difficult to claim that cases have received equal treatments prior to reaching the limit. For example, three calls during the same hour is not likely to be as effective as three calls placed on different days and times of day. Yet they would both reach a three-call limit. [As an aside, it might make more sense to place a lower-limit on "next call" propensities estimated from models that include information about the timings of the call, as Kreuter and Kohler do here.]

In any event, subject to some modification, call limits do imply an adaptive rule where there are two possible design protocols: 1) make another call, 2) stop calling. The rule might take the following form: after the third call, stop if there has never been contact. The tailoring variable is the contact history (ever contact?) and the number of calls. Both of these are drawn from paradata.

In my view, these sorts of stopping rules are adaptive.

### "Responsive Design" and "Adaptive Design"

My dissertation was entitled "Adaptive Survey Design to Reduce Nonresponse Bias." I had been working for several years on "responsive designs" before that. As I was preparing my dissertation, I really saw "adaptive" design as a subset of responsive design.

Since then, I've seen both terms used in different places. As both terms are relatively new, there is likely to be confusion about the meanings. I thought I might offer my understanding of the terms, for what it's worth.

The term "responsive design" was developed by Groves and Heeringa (2006). They coined the term, so I think their definition is the one that should be used. They defined "responsive design" in the following way:

1. Preidentify a set of design features that affect cost and error tradeoffs.
2. Identify indicators for these costs and errors. Monitor these during data collection.
3. Alter the design features based on pre-identified decision rules based on the indi…

### An Experimental Adaptive Contact Strategy

I'm running an experiment on contact methods in a telephone survey. I'm going to present the results of the experiment at the FCSM conference in November. Here's the basic idea.

Multi-level models are fit daily with the household being a grouping factor. The models provide household-specific estimates of the probability of contact for each of four call windows. The predictor variables in this model are the geographic context variables available for an RDD sample.

Let $\mathbf{X_{ij}}$ denote a $k_j \times 1$ vector of demographic variables for the $i^{th}$ person and $j^{th}$ call. The data records are calls. There may be zero, one, or multiple calls to household in each window. The outcome variable is an indicator for whether contact was achieved on the call. This contact indicator is denoted $R_{ijl}$ for the $i^{th}$ person on the $j^{th}$ call to the $l^{th}$ window. Then for each of the four call windows denoted $l$, a separate model is fit where each household is assum…

### Goodhart's Law

I enjoy listening to the data skeptic podcast. It's a data science view of statistics, machine learning, etc. They recently discussed Goodhart's Law on the podcast. Goodhart's was an economist. The law that bears his name says that "when a measure becomes a target, then it ceases to be a good measure." People try and find a way to "game" the situation. They maximize the indicator but produce poor quality on other dimensions as a consequence. The classic example is a rat reduction program implemented by a government. They want to motivate the population to destroy rats, so they offer a fee for each rat that is killed. Rather than turn in the rat's body, they just ask for the tail. As a result, some persons decide to breed rats and cut off their tails. The end result... more rats.

I have some mixed feelings about this issue. There are many optimization procedures that require some single measure which can be either maximized or minimized. I think thes…