Table A-1: Other Estimates of Price Dispersion in US Mortgage Market
Paper Data Main Findings Comments
Agarwal et
al. (2023)
Mortgages originated between 2001 and 2011
and insured by one of the GSEs. 85% of orig-
inations are from 2001-2009.
Residual standard deviation of 39bp (after
controlling for origination quarter, state, and
various loan and borrower characteristics).
90th-10th percentile gap in residual is 90bp.
Interest rates are adjusted for points and
fees. Adding lender-by-quarter fixed effects
appears to have little effect on residual dis-
persion (see their Figure A1.C).
Alexandrov
and
Koulayev
(2017)
Rate sheet data (offers data) for 31 lenders
from Informa. Calculate dispersion in offered
rates for characteristics of 1.3M loans origi-
nated in 2014.
Focus is on the spread between highest and
lowest offer across lenders. The average of
this spread is 50bp, though with variation
across loan types (10th percentile is around
33bp, 90th percentile around 69bp).
No data on transactions. Argue that wide
dispersion in offers implies borrowers don’t
shop much, and that search costs, incorrect
beliefs about dispersion, and non-price lender
preferences matter (with some evidence from
NSMO survey data).
Ambokar
and Samaee
(2019)
Fannie Mae and Freddie Mac public loan-
level data on originations from 1999 to 2016.
Residual standard deviation of 27bp (after
controlling for origination month, FICO bins,
LTV bins, 3-digit zip code and other loan
characteristics available in these data, as well
as originator fixed effects).
Data do not contain information lock date or
fees/points. Only relatively large originators
are individually identified.
Gurun et al.
(2016)
Privately securitized adjustable-rate mort-
gages through 2006 (data source: LoanPer-
formance)
Find 95th-5th percentile gap in residual re-
set rate of 310bp; also construct “lender ex-
pensiveness”measure from residual; 95th-5th
gap there averages 280bp.
Reset rate typically applies 2+ years after
origination, if borrower does not refinance
sooner. Main focus is on relationship be-
tween lender expensiveness and advertising.
McManus et
al. (2018)
PMMS survey data (offer rates at lender level
for a first-lien, prime, conventional, conform-
ing home purchase mortgages with a loan-to-
value of 80%) from 1995 through 2017.
For most periods, the standard deviation of
offer rates ranges from 15 to 25 bp (mostly
below 20). During the global financial crisis,
the rate dispersion peaked at about 45 bp.
On a specific date in 2018, show that range
of offers is about 90bp.
No data on transactions. Calculate potential
gains from shopping simply based on calcu-
lating the minimum rate obtained from X
random searches (for X = 1 to 5).
Woodward
and Hall
(2012)
Sample of 1,500 FHA loans from six weeks in
2001; brokered mortgages only.
90th-10th percentile gap in fees paid to bro-
kers (upfront fee + yield spread premium) is
about 300bp.
300bp in upfront costs would correspond
to about 75bp in rates just from broker
costs; there might be additional rate varia-
tion across borrowers.
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