Changelog
AER 1.2-16
CRAN release: 2026-02-09
- Omitted some examples and updated corresponding output for CRAN checks.
AER 1.2-12
CRAN release: 2024-02-03
- Omitted some examples and updated corresponding output for CRAN checks.
AER 1.2-11
- Rather than quitting from examples in the manual pages, when the required packages are not available, the examples now
stop()in non-check settings.
AER 1.2-10
CRAN release: 2022-06-14
Improvements in
coeftest()methods formultinomandpolrobjects to be compatible with recent extensions inlmtest>= 0.9-38.Fixed a bug in the tests for weak instruments in
ivdiag(): Interactions likex1:x2andx2:x1were considered to be different variables although they are in fact equivalent. (Reported by Arne Henningsen and Ghislain Dossou.)Use fully-qualified calls to
survival::survreg()andsurvival::Surv()within thetobit()function so thatAER::tobit()can be called without attaching the package (reported by Bill Denney).Started replacing examples with repeated
with()variable transformations with a singletransform().
AER 1.2-9
CRAN release: 2020-02-06
Some examples from the AER book lead to small numeric differences across different platforms. Hence, these have been excluded now from
tests/Ch-*.Rwith anIGNORE_RDIFFcomment for CRAN.The examples on the manual pages for the books
CameronTrivedi1998,Greene2003,WinkelmannBoes2009are now excluded from testing to reduce the computational demands on CRAN. The corresponding analyses are mostly available on the manual pages for the underlying data sets, though.
AER 1.2-8
CRAN release: 2019-11-08
- Starting from
survival>= 3.1-6 the survival provides (or corrected) some standard S3 methods forsurvregobjects:fitted(),nobs(),weights(),vcov(). Previously, these were registered by AER” in order to work for “tobit” objects. For now, AER registers the methods fortobitobjects. In the future, the methods will be dropped by AER altogether and inherited from survival (when AER depends on survival >= 3.1-6).
AER 1.2-7
CRAN release: 2019-07-31
Diagnostic tests
ivdiag()for weighted instrumental variables regression was incorrect as weights were erroneously ignored (detected and tested by Jonathan Siverskog).vcov()method forsurvregobjects insurvivalcurrently (version 2.44-1.1) provides no row/column names. Hence, a newvcov()method fortobitobjects was added inAERmimicking the naming conventions fromsurvival:::summary.survreg. Analogously, abread()method was added fortobitobjects that calls thevcov()method internally.linearHypothesis()method fortobit()objects no longer assumes that a scale parameter was estimated as part of the model. This enables the somewhat unusual but possible case ofsummary(tobit(..., dist = "exponential")).In examples/demos/tests with calls to
set.seed(...)the RNG version is now fixed tosuppressWarnings(RNGversion("3.5.0"))to keep results exactly reproducible after fixing RNG problems in R 3.6.0.New errata item in
vignette("AER", package = "AER"): The formula interface forpgmm()has changed. As ofplmversion 1.7-0, the functiondynformula()is deprecated. Examples, tests, and demos have been adapted accordingly.In
tests/Ch-Intro.Rsomequantregcomputations are now wrapped intotry()because thesummary()method yields non-finite standard errors on some platforms.In
?CameronTrivedi1998one version of the negbin-negbin hurdle model is now wrapped intotry()because evaluating the log-likelihood at the given start values becomes too unstable on some platforms.
AER 1.2-6
CRAN release: 2018-12-28
Added
update()method forivregobjects that correctly handles the two-part right-hand side of the formula (suggested by Matthieu Stigler).Use
pdata.frame()instead ofplm.data()as preparation for modeling withplmand certainsystemfitfunctions (requiressystemfit1.1-20).The
model.matrix()method forivregobjects erroneously dropped the dimension of single-column projected regressor matrices. This propagated to theestfun()method and hence lead to problems with sandwich covariances (reported by Justus Winkelmann).In a bug fix the
survivalpackage changed the internal structure ofsurvreg()$ystarting fromsurvival2.42-7. This leads to incorrectsummary()output fortobitobjects which has been worked around now. Thanks to Terry Therneau for pointing out the problem and suggesting a fix.
AER 1.2-5
CRAN release: 2017-01-06
Support for aliased coefficients in
ivreg()(suggested and tested by Liviu Andronic).New data sets
GoldSilver,MotorCycles2andMSCISwitzerland, taken from Franses, van Dijk, Opschoor (2014): “Time Series Models for Business and Economic Forecasting”, 2nd ed. For replication of the corresponding examples, several packages were added to the list of ‘suggested’ packages (includingfGarch,forecast,longmemo,rugarch,vars).Small improvements in
DESCRIPTION/ImportsandNAMESPACEforR CMD check.
AER 1.2-3
CRAN release: 2015-02-24
Package
splinesis loaded explicitly if needed (rather than assuming that it is loaded along withsurvival).Some URLs in the manual pages had been outdated and are updated (or omitted) now.
AER 1.2-2
CRAN release: 2014-01-28
Another bug fix in the new
summary(ivreg_object, diagnostics = TRUE). If sandwich standard errors (or othervcov) were used, the chi-squared form rather than the F form of the diagnostic Wald tests was computed and hence the p-values were incorrect.If there is more than one endogenous variable,
summary(ivreg_object, diagnostics = TRUE)now reports separate tests of weak instruments for each endogenous variable.
AER 1.2-1
CRAN release: 2013-11-07
Bug fix in the new
summary(ivreg_object, diagnostics = TRUE). If there is more than one endogenous variable, the degrees of freedom (and hence the associated p-values) for the Sargan test were too large.The examples employing
rglfor 3d visualizations (e.g., for theSIC33data) are not tested anymore inR CMD check(asrglcurrently has some problems on CRAN’s checks for OS X).
AER 1.2-0
CRAN release: 2013-10-01
The
summary()method forivregnow has adiagnostics = FALSEargument. If set toTRUE, three diagnostic tests are performed: an F test of the first stage regression for weak instruments, a Wu-Hausman test for endogeneity, and a Sargan test of overidentifying restrictions (only if there are more instruments than regressors).Added new data set
EquationCitationsprovided by Fawcett & Higginson (2012, PNAS).Changes in Depends/Imports/Suggests due to new CRAN check requirements. In particular, the
Formulapackage is now only imported (but not loaded into the search path).
AER 1.1-9
CRAN release: 2011-12-10
Recompressed data sets in package to reduce file storage requirements.
ivreg()failed when used without instruments. Now fixed.The
summary()forivregdisplayed the degrees of freedom of the overall Wald test incorrectly (although the p-value was computed correctly).Some technical changes for new R 2.14.0, e.g., adding
Authors@RinDESCRIPTION, recompressing data, etc.
AER 1.1-8
CRAN release: 2011-06-18
The hat values for instrumental variables regressions are now computed in the
hatvalues()method and not withinivreg.fit()to save computation time for large data sets.Added
nobs()method forsurvregobjects (and thustobitobjects). Modifiedivregobjects so that defaultnobs()methods works.Labeling in
coeftest()method formultinomobjects with binary responses has been fixed.Example 21.4 in
?Greene2003now employs the scaled regressorfincome/10000.
AER 1.1-7
CRAN release: 2010-10-13
- Adapted some example in
?Greene2003in order to work both with the old and newdynlmpackage.dynlm()now provides convenient support for linear time trends viadynlm(y ~ trend(y))etc.
AER 1.1-6
CRAN release: 2010-07-29
- Adapted code/examples/tests to new
carversion which has deprecatedlinear.hypothesis()in favor oflinearHypothesis().
AER 1.1-5
CRAN release: 2010-06-21
CPS1985now has 534 observations (not 533 as in prior releases), the original observation 1 had been omitted inadvertently. See also the errata invignette("AER", package = "AER").Data and examples for Winkelmann and Boes (2009), “Analysis of Microdata” (2nd ed.) have been added. For details and extensive (but not quite complete) replication code see
help("WinkelmannBoes2009")as well ashelp("GSS7402")andhelp("GSOEP9402").As announced in the changes for version 1.1-0 of the
AERpackage, the variableearningshas now been removed from thePSID1976(aka Mroz) data. In 1.1-0 it was renamed towageto avoid confusion with other data sets.The
coeftest()method forpolrobjects used to return wrong standard errors (and hence wrong z tests) for the last intercept. This was caused by an inconsistency between thesummary()andvcov()methods forpolrobjects which has been improved in recent versions of theMASSpackage. The correct results are computed bycoeftest()forpolrobjects computed withMASSversion >= 7.3-6. See also the errata invignette("AER", package = "AER").The paper describing the various versions of the
Grunfelddata has been accepted for publication in the German Economic Review. An updated version of the manuscript and associated replication files – mostly based ondata("Grunfeld", package = "AER")– is available from https://www.zeileis.org/grunfeld/.Added
lrtest()method forfitdistrobjects with intelligible model name (instead of the usualformulafor formula-based models).
AER 1.1-3
CRAN release: 2009-05-21
- Added
PSID7682data set which contains the full Cornwell & Rupert- panel data for the years 1976-1982. This should be used for estimation of the Hausman-Taylor model in Exercise 6 from Chapter 3 (instead of
PSID1982which does not provide panel data but only the cross-section for 1982). See the errata and the manual page for more details.
- panel data for the years 1976-1982. This should be used for estimation of the Hausman-Taylor model in Exercise 6 from Chapter 3 (instead of
- Fixed overall Wald test in
summary()fortobitmodels with intercept only.
AER 1.1-2
CRAN release: 2009-03-19
New errata item in
vignette("AER", package = "AER"): The comment regarding the output from the Johansen test (p. 169) is in error. The null hypothesis of no cointegration is not rejected at the 10% level (only at 15% level).Enhancements of the
CigarettesSWexamples from Stock & Watson.Fixed overall Wald test in
summary()fortobitmodels without intercept.Improved
rglcode in theSIC33example.The variable
genderin theParade2005data set was wrong for observation 70. It is now"male"(not"female").
AER 1.1-1
CRAN release: 2009-03-08
- A new improved version of the
plmpackage is available from CRAN (version 1.1-1). This fixes a bug in thesummary()ofplmobjects, see the vignette/errata for details. Furthermore, there is now avcovHC()method forpanelmodelobjects: It gives equivalent results topvcovHC()but is now the recommended user interface and hence used in the examples of some manual pages (see e.g.?Fatalities).
AER 1.1-0
CRAN release: 2009-02-06
Some variable names in the
PSID1976(aka Mroz) data have been renamed:earningsis now calledwage(to avoid confusion with other data sets), the previous variablewageis renamed asrepwage(reported wage). Currently,earningsis kept; it will be removed in future releases.Documentation of the
Grunfelddata has been enhanced and updated. Much more details are available in a recent technical report: Kleiber and Zeileis (2008), “The Grunfeld Data at 50”, available from https://doi.org/10.57938/c1925b32-0b27-490f-b593-42da650c196c.Multinomial logit examples using Yves Croissant’s
mlogitpackage have been added for theTravelModeandBankWagesdata sets.Vignette/errata updated.
AER 1.0-0
CRAN release: 2008-08-26
Official version accompanying the release of the book (contains all code from the book in demos and tests)
See the new
vignette("AER", package = "AER")for an overview of the package and a list of errata.