I have posted quite a bit about the importance of social distancing, and some might be tempted to think that this means that I agree with every policy aimed at slowing the spread of COVID-19 regardless of the cost. This is simply not the case. I focus on explaining the epidemiological side of COVID-19 and the thought process behind different mitigation strategies because that is my area of expertise. I have spent years studying epidemics as part of my research dating back to graduate school. The economic side and the policy side are also extremely important, but, I have commented on them less often because I am less qualified to do so.
The scientific evidence is abundantly clear that decreasing (1) the contact rate between individuals and (2) the probability of transmission are effective ways to slow the spread of infectious disease and in doing so reduce the burden on the healthcare system and the number of deaths. So we know what behaviors can reduce the spread of disease. It is less clear (at least to me) which policies are necessary and appropriate for prompting people to adopt those behaviors. So although you may hear me say that I support existing policies (i.e. I will abide by them and I think they should be given a chance to succeed now that they are in place), that does not mean that I believe that they were the best possible policy that could have been adopted in the first place.
But how could one determine the best possible policy? If our goal is simply to reduce the spread of this disease, then we would do everything in our power to decrease the two factors I mentioned before: the contact rate and the probability of transmission. However, no one and I mean NO ONE is advocating for that. Why? Because that would mean ignoring other important factors. If reducing the spread of disease causes harm in other areas, then that needs to be taken into account.
The reality is that slowing the spread of disease by social distancing has ripple effects in other aspects of life. Less people on the roads means less traffic fatalities and less pollution. That could result in many averted deaths over the long haul even if those deaths would have had nothing to do with COVID-19. At the same time, although a rise in unemployment was inevitable, mandatory closures increase the unemployment rate which will probably result in higher suicide rates, more substance abuse and worse nutrition. This response could cause additional deaths on top of the ones directly caused by COVID-19.
As an example, I just stumbled across an open letter by the head of the local hospital in my town. The state of Michigan ordered the cancellation of all elective procedures and as a result, this hospital is in danger of becoming insolvent and having to close its doors. As stated in the letter:
“When rural hospitals close, people die. There is no way around it. Rural patients are forced to drive an hour or more to receive healthcare at larger health systems in larger towns, even when suffering heart attacks, strokes, birthing complications and other time-sensitive health emergencies. Without quick access to an emergency room, operating room or clinic, lives are lost. “
This is a ripple effect that needs to be considered when evaluating the lockdown policy and its scope.
The point is that our goal should not just be to minimize the number of COVID-19 cases. It should be to minimize the total harm to society (See PS for a comment on this). This notion of total harm is fuzzier than the total number of cases. It includes the intended consequences and the unintended consequences. It includes the number of cases and deaths directly attributable to COVID-19, but it also includes the indirect effects including the economic fallout. It should consider the mental health of our population as well as the physical health. It should include the suffering people experience and the value of the freedom that is lost. Many of these things are difficult (if not impossible) to quantify!
In math, we would call this a multi-objective optimization problem. The goal is to find the best solution to the problem, but the notion of best depends on a variety of factors AKA objectives. For example, one objective might correspond to the loss of life and another might correspond to the loss of economic output. As we change the inputs (behavior and policy), one objective might decrease (less loss of life is good!) while another increases (more loss of jobs is bad!).
As a simple illustration, suppose x measures the intensity of social distancing with x=1 meaning total lockdown and x=0 means changing absolutely nothing. Suppose that f(x) measures the loss of life and g(x) measures the loss of economic output (and any suffering that results from those losses) for a given value of x. It would be reasonable to expect that f(x) decreases as x increases and g(x) increases as x increases. This means that there is no way to minimize both f(x) and g(x) at the same time. How then can we determine the best course of action (i.e. find the value of x that leads to best possible policies/behaviors)?
Before you can even talk about the best solution to a problem like this you would need to determine how you measure best. In other words, you would need to describe the tradeoff between the different objectives. The most common way to do this is to assign a weight (or importance) to each objective. Suppose w represents the weight assigned to the loss of life and (1-w) represents the weight assigned to economic losses. You could construct a new combined objective function: h(x)=w f(x)+(1-w) g(x) that combines these two objectives into a single number. In this context, w=0 would mean you only care about the economy (h(x)=g(x)) and w=1 would mean you only care about the loss of life (h(x)=f(x)). I think all of us would fall somewhere in between those extremes.
Once a weight has been assigned you can apply mathematical tools from calculus to find the best solution. This assumes, of course, that you have already modeled how changes in x affect each objective, which is easier said than done, but I digress.
The problem is that everyone has different beliefs and preferences and therefore we would each assign different values to the weight w. This means that even if we agree on the model itself (exactly how each policy will affect the outcome) we will still disagree on the best solution. Because each of us have competing notions of “best” due to the different weights, what I consider to be the optimal solution, may be suboptimal for you and vice versa.
In light of this, should we throw models and data out the window and go with our gut? I don’t think so. Models should be an essential part of the decision-making process because they are the only tool we have for measuring and comparing and estimating and forecasting. However, models are only as good as the assumptions they are based on, so we need to use them carefully and transparently with those assumptions in mind.
Should we give up on discussing and debating with each other about the merits of different approaches? I don't think that is warranted either. We are all in this together and we will only be able to respond effectively if we all buy in to the solution. In light of this, I believe that an appropriate response is to all of this is to continue the discussion, and as we do so to:
(a) Be aware of the fact that we all assign different weights to some of the objectives that are in play. Even if you don’t consciously think about this an optimization problem, you still have some implied weight in the way that you make decisions. If other people have different implied weights, then they will come to a different conclusion about the best course of action.
(b) Be open and honest about the assumptions we are making when discussing these issues. Otherwise, there is no way to have a civil and productive debate.
(c) Avoid viewing this debate about this crisis in ideological terms. It should not be about left vs right or health vs the economy. Why can’t it be us vs the virus?
(d) Avoid framing these questions as all or nothing propositions. We are not choosing between doing nothing or hiding under our beds until this blows over. There are an array of different policies and behaviors to consider, and each should be evaluated on their own merits.
(e) Be respectful and willing to listen. Deep down, we all want this to be over. Let’s start from there and then work together to find the best way to work toward that goal.
PS I have had a couple of discussions with friends that revealed that our core disagreements were ethical/philosophical. I tend to view most, if not all, of the options on the table as morally acceptable. This is based on my Christian faith and its implications for my beliefs about morality and the role of government. I don’t like restrictive government control; I would like to avoid it if possible; but I do not consider it immoral or unethical under the circumstances. That is why I frame it as an optimization problem. Starting with this assumption, it is natural to talk about finding the best combination of behavioral changes and interventions for dealing with this crisis.
However, some people believe that certain interventions (such as mandatory lockdowns) are morally wrong and unacceptable under any circumstances. If that is the case, then it completely changes the calculus. In that case, it makes sense to oppose these interventions even if they are effective and the benefits outweigh costs. If that is your perspective, then all of this talk about finding the best solution is irrelevant, and there is not much of a point in debating the merits of each option from a health or economic perspective.
So if you are approaching this issue from the perspective that these types of government interventions are morally wrong, then our discussions probably need to begin with the assumptions and worldview that lead to that moral judgement if we are to understand each other.
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