src/HOL/Probability/Probability_Space.thy
changeset 39302 d7728f65b353
parent 39198 f967a16dfcdd
child 40859 de0b30e6c2d2
equal deleted inserted replaced
39301:e1bd8a54c40f 39302:d7728f65b353
    32   "joint_distribution X Y \<equiv> distribution (\<lambda>x. (X x, Y x))"
    32   "joint_distribution X Y \<equiv> distribution (\<lambda>x. (X x, Y x))"
    33 
    33 
    34 lemma (in prob_space) distribution_cong:
    34 lemma (in prob_space) distribution_cong:
    35   assumes "\<And>x. x \<in> space M \<Longrightarrow> X x = Y x"
    35   assumes "\<And>x. x \<in> space M \<Longrightarrow> X x = Y x"
    36   shows "distribution X = distribution Y"
    36   shows "distribution X = distribution Y"
    37   unfolding distribution_def ext_iff
    37   unfolding distribution_def fun_eq_iff
    38   using assms by (auto intro!: arg_cong[where f="\<mu>"])
    38   using assms by (auto intro!: arg_cong[where f="\<mu>"])
    39 
    39 
    40 lemma (in prob_space) joint_distribution_cong:
    40 lemma (in prob_space) joint_distribution_cong:
    41   assumes "\<And>x. x \<in> space M \<Longrightarrow> X x = X' x"
    41   assumes "\<And>x. x \<in> space M \<Longrightarrow> X x = X' x"
    42   assumes "\<And>x. x \<in> space M \<Longrightarrow> Y x = Y' x"
    42   assumes "\<And>x. x \<in> space M \<Longrightarrow> Y x = Y' x"
    43   shows "joint_distribution X Y = joint_distribution X' Y'"
    43   shows "joint_distribution X Y = joint_distribution X' Y'"
    44   unfolding distribution_def ext_iff
    44   unfolding distribution_def fun_eq_iff
    45   using assms by (auto intro!: arg_cong[where f="\<mu>"])
    45   using assms by (auto intro!: arg_cong[where f="\<mu>"])
    46 
    46 
    47 lemma prob_space: "prob (space M) = 1"
    47 lemma prob_space: "prob (space M) = 1"
    48   unfolding measure_space_1 by simp
    48   unfolding measure_space_1 by simp
    49 
    49