{"id":501,"date":"2015-01-06T17:07:26","date_gmt":"2015-01-06T17:07:26","guid":{"rendered":"http:\/\/frees.pajarel.net\/?page_id=501"},"modified":"2015-02-20T18:41:33","modified_gmt":"2015-02-21T00:41:33","slug":"constant-transition-forces-in-the-multiple-decrement-table","status":"publish","type":"page","link":"https:\/\/users.ssc.wisc.edu\/~ewfrees\/actuarial-mathematics\/multiple-decrement-models\/4-fractional-age-assumptions\/constant-transition-forces-in-the-multiple-decrement-table\/","title":{"rendered":"Constant Transition Forces in the Multiple Decrement Table"},"content":{"rendered":"<p>Under this assumption, transition forces are constant <em>within the year<\/em>,<br \/>\n\\begin{eqnarray*}<br \/>\n\\mu_{x+t}^{0j} = \\mu_{x}^{0j} , \\text{ for } 0 \\leq t \\lt 1 .<br \/>\n\\end{eqnarray*}<br \/>\nRecall that<br \/>\n\\begin{eqnarray*}<br \/>\n~ _t p_x^{00} &#038;=&#038; \\exp \\left\\{- \\int_0^t sum_{j=1}^n \\mu_{x+s}^{0j} ~ds<br \/>\n\\right\\}<br \/>\n= \\exp \\left\\{- \\int_0^t \\mu_{x+s}^{0\\bullet} ~ds \\right\\},<br \/>\n\\end{eqnarray*}<br \/>\nwhere \\(\\mu_{x}^{0\\bullet}= \\sum_{j=1}^n \\mu_{x}^{0j}\\) is the total force of transition out of state 0 at age \\(x\\). Thus, under the constant force assumption, we have<br \/>\n\\begin{eqnarray*}<br \/>\n~ _t p_x^{00} &#038;=&#038; \\exp \\left\\{-t \\times \\mu_{x}^{0\\bullet}\\right\\},<br \/>\n\\end{eqnarray*}<br \/>\nand, taking the limit as \\(t \\rightarrow 1\\), we have \\(p_x^{00} = e^{-<br \/>\n\\mu_{x}^{0\\bullet}}\\). Thus, we can write<br \/>\n\\begin{eqnarray*}<br \/>\n~ _t p_x^{00} &#038;=&#038; \\left\\{p_x^{00}\\right\\}^t .<br \/>\n\\end{eqnarray*}<br \/>\nFurther,<br \/>\n\\begin{eqnarray*}<br \/>\n_t p_x^{0j} &#038;=&#038; \\int_0^t ~ _s p_x^{00} \\mu_{x+s}^{0j} ~ ds =<br \/>\n\\mu_{x}^{0j} \\int_0^t ~ e^{- s \\mu_{x}^{0\\bullet}} ~ ds \\\\<br \/>\n&#038;=&#038; \\mu_{x}^{0j} \\frac{1-e^{- t\\mu_{x}^{0\\bullet}}}{\\mu_{x}^{0\\bullet}}~=~ \\frac{\\mu_{x}^{0j}}{\\mu_{x}^{0\\bullet}} (1- (p_x^{00})^t)<br \/>\n\\end{eqnarray*}<br \/>\nAgain, taking the limit as \\(t \\rightarrow 1\\), we have<br \/>\n\\begin{eqnarray*}<br \/>\n\\frac{ p_x^{0j}}{1- p_x^{00}} = \\frac{ p_x^{0j}}{p_x^{0\\bullet}}=<br \/>\n\\frac{\\mu_{x}^{0j}}{\\mu_{x}^{0\\bullet}} .<br \/>\n\\end{eqnarray*}<br \/>\nThus, we may write<br \/>\n\\begin{eqnarray*}<br \/>\n_t p_x^{0j} = \\frac{ p_x^{0j}}{p_x^{0\\bullet}} \\left(1- (p_x^{00})^t\\right) .<br \/>\n\\end{eqnarray*}<\/p>\n<p><div class=\"alignleft\"><a href=\"https:\/\/users.ssc.wisc.edu\/~ewfrees\/actuarial-mathematics\/multiple-decrement-models\/4-fractional-age-assumptions\/\" title=\"4. Fractional Age Assumptions\">&#9668 Previous page<\/a><\/div><div class=\"alignright\"><a href=\"https:\/\/users.ssc.wisc.edu\/~ewfrees\/actuarial-mathematics\/multiple-decrement-models\/4-fractional-age-assumptions\/summary\/\" title=\"Summary\">Next page &#9658<\/a><\/div> <\/p>\n","protected":false},"excerpt":{"rendered":"<p>Under this assumption, transition forces are constant within the year, \\begin{eqnarray*} \\mu_{x+t}^{0j} = \\mu_{x}^{0j} , \\text{ for } 0 \\leq t \\lt 1 . \\end{eqnarray*} Recall that \\begin{eqnarray*} ~ _t p_x^{00} &#038;=&#038; \\exp \\left\\{- \\int_0^t &hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":495,"menu_order":0,"comment_status":"closed","ping_status":"open","template":"","meta":{"jetpack_post_was_ever_published":false},"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/P8cLPd-85","acf":[],"_links":{"self":[{"href":"https:\/\/users.ssc.wisc.edu\/~ewfrees\/wp-json\/wp\/v2\/pages\/501"}],"collection":[{"href":"https:\/\/users.ssc.wisc.edu\/~ewfrees\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/users.ssc.wisc.edu\/~ewfrees\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/users.ssc.wisc.edu\/~ewfrees\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/users.ssc.wisc.edu\/~ewfrees\/wp-json\/wp\/v2\/comments?post=501"}],"version-history":[{"count":4,"href":"https:\/\/users.ssc.wisc.edu\/~ewfrees\/wp-json\/wp\/v2\/pages\/501\/revisions"}],"predecessor-version":[{"id":1617,"href":"https:\/\/users.ssc.wisc.edu\/~ewfrees\/wp-json\/wp\/v2\/pages\/501\/revisions\/1617"}],"up":[{"embeddable":true,"href":"https:\/\/users.ssc.wisc.edu\/~ewfrees\/wp-json\/wp\/v2\/pages\/495"}],"wp:attachment":[{"href":"https:\/\/users.ssc.wisc.edu\/~ewfrees\/wp-json\/wp\/v2\/media?parent=501"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}