Merge pull request #197 from andrjohns/feature/arm_ch7

Updates ARM Ch.7 Models

Author: rok-cesnovar

ARM/Ch.7/congress.stan

@@ -4,11 +4,14 @@ data {
   vector[N] vote_86;
   vector[N] vote_88;
 }
+transformed data {
+  matrix[N,2] x = [vote_86', incumbency_88']';
+}
 parameters {
-  vector[3] beta;
+  real alpha;
+  vector[2] beta;
   real<lower=0> sigma;
 } 
 model {
-    vote_88 ~ normal(beta[1] + beta[2] * vote_86 
-                     + beta[3] * incumbency_88,sigma);
+  vote_88 ~ normal_id_glm(x, alpha, beta, sigma);
 }

ARM/Ch.7/earnings1.stan

@@ -4,10 +4,13 @@ data {
   vector[N] height;
   vector[N] male;
 } 
+transformed data {
+  matrix[N,2] x = [height', male']';
+}
 parameters {
-  vector[3] beta;
-  real<lower=0> sigma;
+  real alpha;
+  vector[2] beta;
 } 
 model {
-  earn_pos ~ bernoulli_logit(beta[1] + beta[2] * height + beta[3] * male);
+  earn_pos ~ bernoulli_logit_glm(x, alpha, beta);
 }

ARM/Ch.7/earnings2.stan

@@ -5,16 +5,15 @@ data {
   vector[N] sex;
 } 
 transformed data {
-  vector[N] log_earnings;
-  vector[N] male;
-
-  log_earnings = log(earnings);
-  male = 2 - sex;
+  vector[N] log_earnings = log(earnings);
+  vector[N] male = 2 - sex;
+  matrix[N,2] x = [height', male']';
 }
 parameters {
-  vector[3] beta;
+  real alpha;
+  vector[2] beta;
   real<lower=0> sigma;
 } 
 model {
-  log_earnings ~ normal(beta[1] + beta[2] * height + beta[3] * male, sigma);
+  log_earnings ~ normal_id_glm(x, alpha, beta, sigma);
 }

ARM/Ch.7/earnings_interactions.stan

@@ -5,19 +5,16 @@ data {
   vector[N] sex1;
 } 
 transformed data {
-  vector[N] log_earnings;
-  vector[N] male;
-  vector[N] height_male_inter;
-
-  log_earnings = log(earnings);
-  male = 2 - sex1;
-  height_male_inter = height .* male;
+  vector[N] log_earnings = log(earnings);
+  vector[N] male = 2 - sex1;
+  vector[N] height_male_inter = height .* male;
+  matrix[N,3] x = [height', male', height_male_inter']';
 }
 parameters {
-  vector[4] beta;
+  real alpha;
+  vector[3] beta;
   real<lower=0> sigma;
 }
 model {
-  log_earnings ~ normal(beta[1] + beta[2] * height + beta[3] * male 
-                             + beta[4] * height_male_inter, sigma);
+  log_earnings ~ normal_id_glm(x, alpha, beta, sigma);
 }

ARM/Ch.7/wells.stan

@@ -3,9 +3,13 @@ data {
   vector[N] dist;
   int<lower=0,upper=1> switc[N];
 }
+transformed data {
+  matrix[N,1] x = [(dist / 100)']';
+}
 parameters {
+  real alpha;
   vector[2] beta;
 } 
 model {
-  switc ~ bernoulli_logit(beta[1] + beta[2] * dist / 100);
+  switc ~ bernoulli_logit_glm(x, alpha, beta);
 }