| Songs | Jeef | Keef | Total |
|---|---|---|---|
| 0 | 0 | 0 | 0 |
| 1 | 13 | -2 | 11 |
| 2 | 18 | -6 | 12 |
| 3 | 24 | -13 | 11 |
| 4 | 28 | -20 | 8 |
| 5 | 30 | -42 | -12 |
DSAN 5450: Data Ethics and Policy
Spring 2026, Georgetown University
Wednesday, April 1, 2026
| Start | End | Topic | |
|---|---|---|---|
| Lecture | 3:30pm | 4:00pm | A Whirlwind Tour of Prisoners’ Dilemmas |
| 4:00pm | 4:50pm | Policy Interventions: Transforming Prisoners’ Dilemmas into Assurance/Invisible Hand Games | |
| Break! | 5:00pm | 5:10pm | |
| 5:10pm | 6:00pm | “Inverse Fairness”(!): Machine-Learning What Policies Value |
Prisoners’ Dilemma feels like a silly math/econ problem at first… then you get brainwashed by pol econ PhD and suddenly see it at the “core” of 95% of global issues
\[ \DeclareMathOperator*{\argmax}{argmax} \DeclareMathOperator*{\argmin}{argmin} \newcommand{\bigexp}[1]{\exp\mkern-4mu\left[ #1 \right]} \newcommand{\bigexpect}[1]{\mathbb{E}\mkern-4mu \left[ #1 \right]} \newcommand{\definedas}{\overset{\small\text{def}}{=}} \newcommand{\definedalign}{\overset{\phantom{\text{defn}}}{=}} \newcommand{\eqeventual}{\overset{\text{eventually}}{=}} \newcommand{\Err}{\text{Err}} \newcommand{\expect}[1]{\mathbb{E}[#1]} \newcommand{\expectsq}[1]{\mathbb{E}^2[#1]} \newcommand{\fw}[1]{\texttt{#1}} \newcommand{\given}{\mid} \newcommand{\green}[1]{\color{green}{#1}} \newcommand{\heads}{\outcome{heads}} \newcommand{\iid}{\overset{\text{\small{iid}}}{\sim}} \newcommand{\lik}{\mathcal{L}} \newcommand{\loglik}{\ell} \DeclareMathOperator*{\maximize}{maximize} \DeclareMathOperator*{\minimize}{minimize} \newcommand{\mle}{\textsf{ML}} \newcommand{\nimplies}{\;\not\!\!\!\!\implies} \newcommand{\orange}[1]{\color{orange}{#1}} \newcommand{\outcome}[1]{\textsf{#1}} \newcommand{\param}[1]{{\color{purple} #1}} \newcommand{\pgsamplespace}{\{\green{1},\green{2},\green{3},\purp{4},\purp{5},\purp{6}\}} \newcommand{\pedge}[2]{\require{enclose}\enclose{circle}{~{#1}~} \rightarrow \; \enclose{circle}{\kern.01em {#2}~\kern.01em}} \newcommand{\pnode}[1]{\require{enclose}\enclose{circle}{\kern.1em {#1} \kern.1em}} \newcommand{\ponode}[1]{\require{enclose}\enclose{box}[background=lightgray]{{#1}}} \newcommand{\pnodesp}[1]{\require{enclose}\enclose{circle}{~{#1}~}} \newcommand{\purp}[1]{\color{purple}{#1}} \newcommand{\sign}{\text{Sign}} \newcommand{\spacecap}{\; \cap \;} \newcommand{\spacewedge}{\; \wedge \;} \newcommand{\tails}{\outcome{tails}} \newcommand{\Var}[1]{\text{Var}[#1]} \newcommand{\bigVar}[1]{\text{Var}\mkern-4mu \left[ #1 \right]} \]

Single, unique Nash equilibrium, and it’s Pareto inferior
(looming in background: unsustainable if total hours/day > 14)
The “Iterated Elimination” Result
| \(\color{#e69f00}B\) | ||||||
| Fish 6h | Fish 8h | |||||
| \(\color{#0072b2}A\) | Fish 6h | \(\color{#0072b2}\cancel{1}\color{black}, \,\) | \(\color{#e69f00}\cancel{1}\) | \(\color{#0072b2}\cancel{0}\color{black},\) | \(\color{#e69f00}\boxed{\mathbf{1.2}}\) | |
| Fish 8h | \(\color{#0072b2}\boxed{\color{#0072b2}\mathbf{1.2}}\color{black}, \,\) | \(\color{#e69f00}\cancel{0}\) | \(\color{#0072b2}\boxed{\color{#0072b2}\mathbf{0.4}}\color{black},\) | \(\color{#009e73}\boxed{\color{#e69f00}\mathbf{0.4}}\) | ||
Boxes = Best Responses:
\[ \begin{aligned} {\color{#0072b2}\text{BR}_A}({\color{#e69f00}\overset{B}{6\textrm{h}}}) &= {\color{#0072b2}8\textrm{h}}, \; {\color{#0072b2}\text{BR}_A}({\color{#e69f00}\overset{B}{8\textrm{h}}}) = {\color{#0072b2}8\textrm{h}} \\ {\color{#e69f00}\text{BR}_B}( {\color{#0072b2}\underset{A}{6\textrm{h}}} ) &= {\color{#e69f00}8\textrm{h}}, \; {\color{#e69f00}\text{BR}_B}( {\color{#0072b2}\underset{A}{8\textrm{h}}} ) = {\color{#e69f00}8\textrm{h}} \end{aligned} \]
Best response is always \(\text{8h}\), no matter what other player does!
\[ \begin{aligned} \implies &{\color{#0072b2}\mathbb{E}[u_A]} = {\color{#e69f00}\mathbb{E}[u_B]} = 0.4 \text{ for now}, \\ &\leadsto \; ? \text{ once fishery collapses (}\textstyle\sum\text{hrs} = 16\text{)} \end{aligned} \]
Pareto Dominance
\(\leadsto\) Operationalizing Power as “second best” outside option(s)
Slightly better for \(A\) \(\implies\) \(A\) accepts:
\[ \begin{aligned} \mathbb{E}[u_A(a_A = \textsf{Reject})] &= \overset{\text{STTP}}{\boxed{0.4}} \; \text{ (prev slide) } \overset{\text{LTTP}}{\color{#e69f00}\boxed{\color{black}\leadsto -\infty}} \\ \mathbb{E}[u_A(a_A = \textsf{Accept})] &= 0.41\cdot 1 + 0.59 \cdot 0 = \boxed{0.41} \\ \mathbb{E}[u_B(a_A = \textsf{Reject})] &= \boxed{0.4} \; \text{ (prev slide) } {\color{#e69f00}\boxed{\color{black}\leadsto 0.39}} \\ \mathbb{E}[u_B(a_A = \textsf{Accept})] &= 0.41\cdot 1 + 0.59 \cdot 1.2 = \boxed{1.118} \end{aligned} \]
\(B\)’s offer = credible threat in both short and long term; same threat from \(A\) would not be credible (\(B\) knows \(A\) would eventually die: \(u_A \leadsto -\infty\))
HW4: observe policy outcome \(o^{\text{TIOLI}}_{B \rightarrow A}\) \(\Leftrightarrow\) social welfare weights \(\omega_B > \omega_A\)
\(\leadsto\) Weber’s descriptive definition of “The State”: Agent with Monopoly on Legal Use of Force (Weber 1919) (remember him?)
An economic transaction is a solved political problem. Economics has gained the title “Queen of the Social Sciences” by choosing solved political problems as its domain. (Lerner 1972)
| \(\color{#e69f00}B\) | ||||||
| Fish 6h | Fish 8h | |||||
| \(\color{#0072b2}A\) | Fish 6h | \(\color{#0072b2}\cancel{1}\color{black}, \,\) | \(\color{#e69f00}\cancel{1}\) | \(\underset{(+1)}{\color{#0072b2}\cancel{0}\color{black}}\underset{\; \leftarrow\vphantom{(+1)}}{,}\) | \(\underset{(-1)}{\color{#e69f00}\boxed{\color{#e69f00}\mathbf{1.2}}}\) | |
| Fish 8h | \(\underset{(-1)}{\color{#0072b2}\boxed{\color{#0072b2}\mathbf{1.2}}}\color{black}\underset{\rightarrow\vphantom{(+1)}}{,} \,\) | \(\underset{(+1)}{\color{#e69f00}\cancel{0}}\) | \(\color{#0072b2}\boxed{\mathbf{0.4}}\color{black},\) | \(\color{#e69f00}\boxed{\mathbf{0.4}}\) | ||
\(\leadsto\)
New game with tax applied
| \(\color{#e69f00}B\) | ||||||
| Fish 6h | Fish 8h | |||||
| \(\color{#0072b2}A\) | Fish 6h | \(\color{#0072b2}\boxed{\mathbf{1}}\color{black}, \,\) | \(\color{#e69f00}\boxed{\mathbf{1}}\) | \(\color{#0072b2}\boxed{\mathbf{1}}\color{black},\) | \(\color{#e69f00}\cancel{0.2}\) | |
| Fish 8h | \(\color{#0072b2}\cancel{0.2}, \,\) | \(\color{#e69f00}\boxed{\mathbf{1}}\) | \(\color{#0072b2}\cancel{0.4}\color{black},\) | \(\color{#e69f00}\cancel{0.4}\) | ||
| \(\color{#e69f00}B\) | |||
| Early | Late | ||
| \(\color{#0072b2}A\) | Early | \(\color{#0072b2}\boxed{\mathbf{4}}\color{black}{,} \color{#e69f00}\boxed{\mathbf{4}}\) | \(\color{#0072b2}\cancel{0}\color{black}{,} \color{#e69f00}\cancel{3}\) |
| Late | \(\color{#0072b2}\cancel{3}\color{black}{,} \color{#e69f00}\cancel{0}\) | \(\color{#0072b2}\boxed{\mathbf{2}}\color{black}{,} \color{#e69f00}\boxed{\mathbf{2}}\) | |
It is not from the benevolence of the butcher, the brewer, or the baker that we expect our meal, but from their regard to their own interest (Smith 1776)
| \(\color{#e69f00}B\) | ||||
| Corn | Taro | |||
| \(\color{#0072b2}A\) | Corn | \(\color{#0072b2}\cancel{2}\color{black}{,} \color{#e69f00}\boxed{\mathbf{4}}\) | \(\color{#0072b2}\boxed{\mathbf{4}}\color{black}{,} \color{#e69f00}\cancel{3}\) | |
| Taro | \(\color{#0072b2}\boxed{\mathbf{5}}\color{black}{,} \color{#e69f00}\boxed{\mathbf{5}}\) | \(\color{#0072b2}\cancel{3}\color{black}{,} \color{#e69f00}\cancel{2}\) | ||
[…I am once again reminding you that] An economic transaction is a solved political problem. Economics gained the title “Queen of the Social Sciences” by choosing solved political problems as its domain
From Ryan Safner’s History of Economic Thought: Welfare Economics
Rotate Greenie’s box 180° and superimpose onto Bluey’s:
[Antecedents (Coase Conditions)] \(\Rightarrow\) «markets produce Pareto-optimal outcomes»
Consequent only true if antecedents hold! Otherwise, proper answer becomes “It depends! Let’s see if data can help us find out!” (Will minimum wage hurt/help blah blah blah… “It depends! Tell me the details!”) (Will new condos blah blah blah yimby nimby…) (Will re-allocating welfare budget from \(X\) to \(Y\) blah blah blah… 👀 HW4)
[Economic inequality] is a social law, something in the nature of man. (Pareto 1896)
We’ve got a [thing] made by men, isn’t that something we should be able to change? (Steinbeck 1939)
Coase Antecedents \(\approx\) equalized power!
\(\neg\)(Coase Antecedents) \(\Rightarrow\) Unequal Power… Puts us in realm of Descriptive Ethics!
[What is] right, as the world goes, is only in question between equals in power; otherwise, the strong do as they please and the weak suffer what they must. [Thucydides (2013); c. 411 BC] (Think of necessary vs. sufficient conditions!)
Like how Gauss-Markov Assumptions \(\Rightarrow\) OLS is BLUE, yet our whole field (at least, a whole class, DSAN5300) built on what to do when G-M Assumptions don’t hold
For policy development, helpful to think through
Our violation: No externalities assumption
Case : Society decides Right to Clean Air \(\prec\) Right to Smoke \(\Rightarrow\) Start at \(E\)
Case Society decides Smoke \(\prec\) Clean Air \(\Rightarrow\) Repeat for \(E' \leadsto X'\)
Last reminder: Externalities \(\Leftrightarrow\) I get reward, others pay costs 🥳
\[ s^*_{\text{Priv}}, x^*_{\text{Priv}} = \argmax_{s,\small\boxed{x}}\left[ p_s s - c_s(s, x) \right] \]
\[ f^*_{\text{Priv}} = \argmax_{f}\left[ p_f f - c_f(f, x) \right] \]
\[ s^*_{\text{Yugo}}, f^*_{\text{Yugo}}, x^*_{\text{Yugo}} = \argmax_{s, f, x}\left[ p_s s + p_f f - c_s(s, x) - c_f(f, x) \right] \]
\[ W(\mathbf{u}) = W(u_1, \ldots, u_n) \Rightarrow W(\mathbf{u})(x) = W(u_1(x), \ldots, u_n(x)) \]
\[ W(\underbrace{v_1, \ldots, v_n}_{\text{Values}})(x) \overset{\text{e.g.}}{=} \omega_1\underbrace{v_1(x)}_{\text{Privacy}} + \omega_2\underbrace{v_2(x)}_{\mathclap{\text{Public Health}}} \]
\[ W(\underbrace{s_1, \ldots, s_n}_{\text{Stakeholders}})(x) = \omega_1\underbrace{u_{s_1}(x)}_{\text{Teachers}} + \omega_2\underbrace{u_{s_2}(x)}_{\text{Parents}} + \omega_3\underbrace{u_{s_3}(x)}_{\text{Students}} + \omega_4\underbrace{u_{s_4}(x)}_{\mathclap{\text{Community}}} \]
\[ \mathbb{E}[Y \mid D = 1, A = 1] = \mathbb{E}[Y \mid D = 1, A = 0] \]
\[ W(u_1, \ldots, u_n)(x) = \frac{1}{n}u_1(x) + \cdots + \frac{1}{n}u_n(x) \]
While the rhetoric of “all men [sic] are born equal” is typically taken to be part and parcel of egalitarianism, the effect of ignoring the interpersonal variations can, in fact, be deeply inegalitarian, in hiding the fact that equal consideration for all may demand very unequal treatment in favour of the disadvantaged (Sen 1992)
| Songs | Jeef | Keef | Total |
|---|---|---|---|
| 0 | 0 | 0 | 0 |
| 1 | 13 | -2 | 11 |
| 2 | 18 | -6 | 12 |
| 3 | 24 | -13 | 11 |
| 4 | 28 | -20 | 8 |
| 5 | 30 | -42 | -12 |


\[ \begin{align*} \max_{m_1,m_2,a_1,a_2}& W(u_1(m_1,a_1),u_2(m_2,a_2)) \\ \text{s.t. }& m_1 + m_2 \leq 14 \\ \phantom{\text{s.t. }} & ~ \, a_1 + a_2 \; \leq 7 \end{align*} \]
DSAN 5450 Week 11: Welfare Weights and Inverse Fairness
Social Welfare Functionals