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International Journal of
            Population Studies                                              Macroeconomic factors and housing dynamics



              where  χ stands for the weight of non-durable    permanently and the government will not collect any
            consumption. The relative risk aversion coefficient is   property tax from it.
            denoted as σ.                                        The housing production function is defined as:

            2.3. Production sector                                                 ν −  1 ν  −  φ
                                                                        ( ) ( ) ( )
                                                                  Y = ZL    1 φ   K h  N h             (VII)
                                                                       h
                                                                   h
            There are two production sectors in our model: the     t   t  t       t  t    
            non-durable goods sector and the housing sector. The
                                                                         h
            former produces  non-housing goods and is referred to   where  Z  refers to the technology in the construction
                                                                        t
                                                                                                        h
            as  the consumption  sector.  The  latter  one builds houses   sector. The new residential investment at time t is Y . The
                                                                                                        t
            like construction companies and is referred to as the   land share in housing production is denoted as 1−φ, and
            construction sector. Both sectors maximize their profits   the capital share is referred to ν. The land, capital, and labor
                                                                                    h
                                                                                           h
            by choosing input factors. Both the capital market and   input are denoted by L ,  K and  N , respectively.
                                                                                 t
                                                                                          t
                                                                                    t
            labor market are frictionless, and there are no restrictions   The construction firms’ problem can be written as:
            on labor flow and capital flow. Thus, in equilibrium, the
                                                                                                      l
                                                                                           r +
            returns  on  both  input  factors  are  paid  the  same  among   max D  , ht k  =  Y p − h  t h  w N − t  t h  ( t  δ )K −  t h  pL t    (VI)
                                                                           +
                                                                               t
                                                                     h
                                                                   h
            sectors. Land, only provided by the government, is taken   { t K  ,NL }
                                                                      , t
                                                                     t
            as a production factor in housing construction.      Every construction company tries to maximize the
                                                                                            h
            2.3.1. Consumption sector                          profit D h,t+k  in each period, where  p  is the relative house
                                                                                            t
                                                               price in units of the non-durable consumption good. p is
                                                                                                           l
                                                      c
            The output of non-durable goods denoted as,  Y , is   the relative land price, which is fixed and set by the
                                                      t
            produced using physical capital and labor input according   government. The government spending G  at time t is fully
            to the Cobb-Douglas production function:           financed by the sale of the land p L . t  t
                                                                                         l
                     ( ) ( )
                    c
                c
               Y = ZK  t c  α  N t c  1 α  −           (III)     The evolution path in the construction sector is:
                t
                    t
                                                                        h
                                                                  K h    I 1   K   h                (VII)

              where  Z  refers to the productivity in the consumption   t 1  t  t
                     c
                     t
                                                                        h
                                                     c
            sector. Capital and labor input are denoted by  K  and,   where  I  stands for the investment in the housing
                                                                        t
                                                     t
            respectively. α is the capital share.              sector.
              Then the firm’s problem can be written as follows:  The law of motion for the aggregate residential housing
                                                               stock Ht is:
               max D    =  Y −  c  wN −  c  ( t  δ )K c  (IV)
                                    r +
                c
               { t KN c }  , ct k+  t  t  t  t                    H t + 1  =  (1 δ−  h )H +  t  Y t h   (VIII)
                 ,  t
                                                                 The houses depreciate at a constant rate δ  Based on
              where  D (c,t+k)  stands for the profit of the company.   the demographic information, we can easily calculate the
                                                                                                    h.
            Physical capital depreciates at a constant rate δ, and r  refers   aggregate house stock at time t:
                                                     t
                            c
            to the interest rate. I  is the investment in the consumption   jJ  ij
                            t
            sector.                                               H    (   it j  t j                    (IX)
                                                                   t
                                                                             P h )
              The evolution path of aggregate capital in the          j1  i1
            consumption sector is:                               where the h is the individual’s optimal housing service
                                                                           j
                                                                           t
                     c
                c
               K t 1   I 1   K   t c             (VI)    consumption at age j and time t.

                     t
              The price of non-durable goods is normalized to 1.  2.4. Government and social security
                                                               Government in our model has three functions: the first one
            2.3.2. Construction sector                         is to collect payroll tax and run the PAYG social security
            The  construction  firm’s  problem  is  similar  to  the   system; the second one is to distribute government
            consumption firm’s problem, except the construction firm   transfers; and the third one is to lease the lands to finance
            uses an additional input: land. Land is only owned and   government spending to maintain function. To simplify,
            provided by the government at a predetermined fixed   we assume that each spending is financed separately. The
            price. The land stock is unlimited, and then the land   aggregate social security pension is equal to the aggregate
            demand of construction firms is determined by the land   tax  collected,  the  accumulated  government  transfers
            price. When a house is built and sold to the household,   are equal to the market value of all the wealth including
            the land ownership is transferred to the house owner   housing and financial assets left by the households who are
            Volume 11 Issue 1 (2025)                        50                        https://doi.org/10.36922/ijps.3645
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