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β€œThe New Normal”: Structural vs.Cyclical U.S.Unemployment
Econometrics II
May 2, 2014
Joshua T. Rome
One topicat the forefrontof U.S.economicdevelopmentoverthe pastseveral yearssince the
financial crisishasbeenunemployment. The catalystof thisdiscourse isnomystery.Unemployment
impactsmanyAmericansandthe relationshipwithGDPisempiricallyverifiable (thesocalledβ€œOkun’s
law”). The mainquestionregardingthe persistentlyhigh levelsof unemployment iswhetherthishas
beena structural or prolongedcyclical effect. Thispaperseekstounderstandthe recentchangesinthe
unemploymentrate inthe contextof the previoussixtyyearsof unemploymentdatathatisavailable.
The firstportionof the analysiswill be composedof lookingatthe patternof the unemploymentrate as
a standalone time series. Followingasolidunderstanding of the historictrend;the unemploymentrate
will be comparedwithtotal jobopeningsforfurthercluestothe nature of the recentunemployment
levels.
Analyzing the data
The firststepin derivingarelationshipbetweenthissetof variablesistosimplyobserve the dataover
time;andto analyze if there are any
trends,seasonalityorotherdiscernible
patterns. We beginbylookingat time
graphs of our mainvariablesbeginning
withunemployment. Aswithmany
macroeconomictime series
unemploymentisstronglytrended,
showingcyclical peaksandtroughs,
althoughvaryingindurationaswell asmagnitude. Itisclear thatlevel of unemploymenttodaystrongly
dependsonthe level of unemploymentyesterday. If modeledasafirstorder autoregressivemodel:
π‘ˆπ‘›π‘’π‘šπ‘π‘™π‘œπ‘¦π‘šπ‘’π‘›π‘‘ 𝑑 = 𝐡0 + 𝐡1 π‘ˆπ‘›π‘’π‘šπ‘π‘™π‘œπ‘¦π‘šπ‘’π‘›π‘‘ π‘‘βˆ’1 + πœ€ 𝑑
The model appearsto be verysignificant,withthe overall level of significance of the F-Statistic
at zero withanR-squaredof almost94%. Unfortunatelythesespurious resultsare anartifact of the high
levelsof autocorrelation. Because ourmodel includesarighthandside dependentvariable any
autocorrelationcausesestimatesof the regressiontobe inconsistentandinvalid;unfortunatelyaswell
the Durbin-Watsonteststatisticwillnotbe validandcannotbe used. Thuswe will use Durbin’sβ€˜h’test
whichisdesignedforexactlythissituation. We firstcompute the DurbinWatsonteststatistic:
DW=.9878363 and from thisstatisticwe can backout our estimate for rho. 𝑃̂ = 1 βˆ’
π·π‘Š
2
andwe
compute thisvalue tobe .50608185. β„Ž =
π‘ƒΜ‚βˆš
π‘›βˆ—
(1βˆ’π‘›βˆ—)𝑆𝐸.𝐡̂
β„Ž = .51√
256
(255).000240
= 32.715 >
2.56 thus we rejectthe null hypothesisthat
there isno autocorrelationforthismodel
specification. If apartial Correlogramis used,
whichis basedon the partial autocorrelation
functionintroducedbyBox-Jenkins,we canclearlysee thatthe firsttwolags of the model lie outside of
the 95% confidence interval andthusare notrandom. The coefficientonthe original model alsomight
seemtosuggesta unitroot as it isveryclose to one (.96); andthe dickeyfullertestfora unitroot would
be appropriate totest forthis. The resultforthe dickeyfullertestwiththree laggedtermsandatrendis
significantwithap-value of .0385; thuswe rejectthe null hypothesisof arandom-walk.
The processof correctlyspecifyingthe model reliedonsimilarbutunrelatedintuition of how
businesscycleswork. Inthe 1950’s manyeconomistsdescribedthe businesscycle intermsof alag on
investmentdecisiondependingonthe growthof the economy. The resultingspecificationforthis
phenomenonwasaβ€œsecondorderdifference equation”where the dependentvariable wasafunctionof
the difference of the laggedfirstdifference of thatvariable. Ingeneral the systemcanresultin
dampeningoranti-dampeningeffectsorstable peaksandtroughs;andof course applicable toother
fields. Basedonthisintuitionthe model forunemploymentisestimated usingaportion of the sample
(observations 1through50) witha laggedtermand a laggedfirstdifference term.
π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ = 𝐡0 + 𝐡1 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘βˆ’1 + 𝐡2( π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘βˆ’1 βˆ’ π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘βˆ’2)+ πœ€ 𝑑
Thismodel isverysignificantwithlow RMSEwhichisgoodfor prediction. Generatingaprediction
variable we cantestthe model we cantestthe model forthe remainingportionof the sample from
1962-2014. The resultsof this out-of-sampleforecastare verytightlyfitaroundthe actual datawitha
meanresidual of .1621 as the difference betweenthe actual unemployment.
There are twomainsourcesof uncertaintyregardingprediction;inthismodel aswell asany
other. If the true valuesof all of the modelscoefficients wereknown;the rootmeansquarederror
wouldbe the standarddeviationof the forecastwhichwe couldassume the errortermisnormally
distributedaboutthe mean. Itisnot possible toknow the true value of the coefficients,becausefor
each sample thatisdrawn;new coefficientswillbe estimated. Tocompute the variance of the estimate
Var(Ρ”) we compute Var(𝑦 βˆ’ 𝑦̂) whichequalsVar(𝑦̂)+Var(y) –2Cov(𝑦̂, 𝑦).
Mathematically;the implicationsof thismodel are numerous. Firstlythe modelimpliesalong-
run unemploymentrate of 5% basedon the data. Thiscan easilybe shownby solvingforthe steady
state where π‘₯ 𝑑 = π‘₯ π‘‘βˆ’1 = π‘₯ π‘‘βˆ’2
Thus: π‘₯βˆ— = .75 + .85π‘₯βˆ— + .55( π‘₯βˆ— βˆ’ π‘₯βˆ—)
Resultingin: .15π‘₯βˆ— = .75
𝐷𝑖𝑣𝑖𝑑𝑒 𝑏𝑦 .15
β‡’ π‘₯βˆ— = 5
Thismodel wasestimated
fromthe sample from
1950-1962, all other
estimatesare out-of -
sample forecasts;from
whichwe observe thatthe
model fitsthe datavery
closely.
Economicallythismaynotbe the mostgranularapproach to estimatinganequilibrium
unemploymentlevel;butthe figure doesappeartobe reasonable. IndeedSt.LouisFederal reserve data
estimatesNROUthe natural rate of unemploymentwithameanvalue of 5.55% anda value exactly
equal to5% fromthe years2000-2009. A more accurate predictionof the longrunβ€œnatural”level of
unemploymentshouldtake intoaccountdemographicsof the population. Anadditional implicationof
thismodel specificationisthat the coefficientof the laggedfirstdifference at.55 is that the specification
isunstable;butwithdampeningeffect. Inotherwordsany shocksto the systemwill resultinsmaller
and smallerdifference fromthe steadystate level;the systemisdynamicallystable.
For the nonmathematical non-statisticalreaderwhatwe learnfromthismodel isthe
dependencyof the currentlevel of unemploymentonpreviouslevelsof unemployment. Predictionwith
thismodel issomethingakintopredictingthe weather tomorrow bylookingoutthe window today;
brightand sunnyandseventywe cansay withsome certaintythatit ishighlyunlikelytosnow.With
unemploymentatagivenlevel we canmake similarobservations. Thismodel alsomakesanother
implicitpredictionof alongrun rate of unemploymentof five percent,althoughthe accuracyof this
predictioncanbe greatlyimprovedwithothereconomicdatasuchas populationdemographics.
Nowthat we understandthe nature of the unemploymentdataovertime we shiftouranalysis
towardsthe recenttrend. The unemploymentrate hadnot reachedheightsof levelsabove 8% since the
1980’s, and yearslateraftera recoveryinequitypricesthe unemploymentrate isstill atitshighestlevel
0
2
4
6
8
10
12
0 10 20 30 40 50 60
Thisdiagramillustratesthe dynamic
stabilityof the model specifiedfrom
the regression. The firstfew
observationsare takenfromthe
actual data;the restare the
predictionsbasedonthe model.
Randomshocksare exogenously
introducedat32-38 and40 to
illustrate the dynamicstability.
inat leastone decade. Inorderto understandthistrendwe mustturnto the Beveridgecurve that
relatesthe numberof nonfarmpayroll openingstothe unemploymentrate.
In the figure we see the monthly dataof the two time seriesplottedagainsteachother fromthe
yearsDec 2000- Mar 2014 formingthe so-calledBeveridgeCurve. Itappearsobviousthatthere isa
structural differencebetweentwodifferenttime periods;visuallyone couldidentifytwolinesthatbest
fitthe data. Basedon intuitionthere isadownwardsloping
line whichwe specifyas (RestrictedModel):
π½π‘œπ‘ π‘‰π‘Žπ‘π‘Žπ‘›π‘π‘¦ π‘…π‘Žπ‘‘π‘’π‘‘ = 𝛽0 + 𝛽1 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ + πœ€ 𝑑
Our coefficientof betaone isbelievedtobe negative; which
the regressionconfirms. Inallowingthe slopeandcoefficient
to be differentforthe twodifferentperiodswe definea
categorical dummyvariable 𝑑𝑖 thatistrue for all periodsafterAugust2009. The specificationof the
secondperiodmodel is:
π½π‘œπ‘ π‘‰π‘Žπ‘π‘Žπ‘›π‘π‘¦ π‘…π‘Žπ‘‘π‘’π‘‘ = ∝0+∝1 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ + πœ€ 𝑑
In orderto create a more parsimoniousdefinitionof ourmodel inone equationwe mustdefinethe
differencesbetweenthe twoseparate modelcoefficients: Let 𝛿1 =∝0βˆ’ 𝛽0 𝛿2 =∝1βˆ’ 𝛽1
The unrestricted model: π½π‘œπ‘ π‘‰π‘Žπ‘π‘Žπ‘›π‘π‘¦ π‘…π‘Žπ‘‘π‘’π‘‘ = 𝛽0 + 𝛽1 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ + 𝛿1 𝑑 𝑖 + 𝛿2 𝑑𝑖 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ + πœ€ 𝑑
Afterexecutingthe regressionof boththe restrictedandunrestrictedregressionswe are able to
performa chowtestof structural difference. The null hypothesisisthatthe unrestrictedmodelis ∝0=
𝛽0 π‘Žπ‘›π‘‘ ∝1= 𝛽1while the alternative hypothesisisthatthe twoare in fact different.
ChowTest
( π‘†π‘†πΈπ‘Ÿπ‘’π‘ π‘‘π‘Ÿπ‘–π‘π‘‘π‘’π‘‘βˆ’π‘†π‘†πΈ π‘’π‘›π‘Ÿπ‘’π‘ π‘‘π‘Ÿπ‘–π‘π‘‘π‘’π‘‘)βˆ—
1
π‘ž
π‘…π‘’π‘ π‘‘π‘Ÿπ‘– 𝑐 𝑑𝑖 π‘œ 𝑛𝑠
𝑆𝑆𝐸 π‘’π‘›π‘Ÿπ‘’π‘ π‘‘π‘Ÿπ‘–π‘π‘‘π‘’π‘‘βˆ—
1
π‘›βˆ’π‘˜
=
3.098836765
0.025153714
= 123.19 > 4.605
The sum of squarederrorforthe unrestrictedmodelis 3.89882567, with155 denominatordegreesof
freedom. The Restrictedsumof squarederroris 10.0964992 and the numberof restrictionsistwo
correspondingtothe numeratordegreesof freedom. Giventhese degreesof freedomthe chow testwe
can rejectthe null hypothesisthatthere isnostructural break at the 1% significance level.
The cause generallyattributedtothe shiftinthe Beveridgecurve isincreasedfrictionsin
matchingbetweenemployeesandemployers. Followingthe greatrecessionunemploymentbenefits
were greatlyextendedtobeyondone year;impeding searchersfromincreasingtheireffort,thus
decreasingmatchingefficiency. Structurallythe principallyaffectedindustryof the crisisfollowingthe
housingboomhadbeenthe constructionindustry. Thisindustryhasrelatively lessfrictioninmatching
compared to otherhigherskill industries thathave lesshirespervacancy suchas engineering. Inan
article fromthe IMF EconomicReviewHobijnandSahinattribute muchof this shiftbetweenthese two
factors1.
Hobijn’sandSahin’sstudywasa longitudinal analysisof thirteencountriesoverfifteenyears.
Interestingfindingsof theirresearch are thataside fromthe U.S. onlythree othercountriesexperienced
a rightwardshiftinthe Beveridge curve: Portugal,Spain,andthe UnitedKingdom. (The othercountries
analyzedinthe sample were Australia,Austria,Belgium, France,Germany,Japan,Netherlands,Norway
and Switzerland.) Whatthese three countrieshadincommonwasa disproportionate decline in
construction, acorollaryof the steepdeclinesinhousingprices. Inaddition,the researchwasputintoa
historical perspectivewithBeveridgeshiftsof the 70’s and 80’s that had reversedtheirrightwardshift
followingrecessions. The conclusionsof theiranalysis are thatthe rate of adjustmentof U.S.labor
relative toothercountriesisveryhigh,andgiventhat unemploymentinsurance increasesare not
permanent;the questioniswhenthiscyclical effectwill subside.
Shiftingfocustothe latestiterationof the Beveridge Curve;althougharightwardshifthas
occurredwhichis consistentwithβ€œstructural unemployment”,the curve appearstobe on a path back to
itspreviousstructural levelslendingsupporttothe β€œprolongedcycle”argument. The observations are
connectedintime anddecreasinginunemploymentwhilstincreasinginNonfarmjobopenings. This
componentof the recenttrendiscyclical. But itis importanttonote that the trend isnot a straightline,
nor convex asthe Beveridge Curve isgenerallyportrayed. Thisnonlinearstructure resemblinga
downwardopeningparabolacanbe modeledby
regressingnonfarmjobopenings onafirstorder
β€˜UNRATE’ term witha squared β€˜UNRATE’ term. The
coefficientof the squaredtermisexpectedtobe
negative because the curve isdownwardopening,and
giventhe tightbandof variationthe model is
expectedtobe verystatisticallysignificantwithahighr-squared.
Specification: π½π‘œπ‘ π‘‰π‘Žπ‘π‘Žπ‘›π‘π‘¦ π‘…π‘Žπ‘‘π‘’π‘‘ = 𝛽0 + 𝛽1 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ + 𝛽1 π‘ˆπ‘π‘…π΄π‘‡πΈ1
2
+ πœ€ 𝑑
The regressionof the newmodel satisfiedall of the apriori assumptionsbut withone unique concern,a
verystatisticallyinsignificantconstantterm. Afterconsiderationof the context;the unemploymentrate
isrelativelyfarfromzeroconsideringthe spacingof the observationsandquantityof observations. In
thiscontextthe lowsignificanceof the constanttermisunimportantandmerelyreflectsalarge distance
fromthe y axisfromthe observations. Economically the empiricallyderivedcurve lendsevidence tothe
prolongedbusinesscycle theoryregardingthe unemployment. Inthe contextof the previousBeveridge
curve ex ante the greatrecession,the model predictsthatwe are on a path that leadstothe old
structure of the Beveridge Curve. The currenttrendthuscan be decomposedintotwocomponents;a
currentcyclical trendof reducedunemploymentandincreasedjobopenings,andaleftwardshifttothe
olderlevelsof matchingefficiency. As
extensionsof unemploymentinsurance
are eliminatedandthe housingmarket
recovers,higherturnoverpositionswill
constitute alargercompositionof the
overall USjob marketandlabor market
efficiencywillslowlyreturn. Although
the economyhasrecovered
significantlysince the greatrecession,the recoveryhasbeenslow goingandiscontinuingtothisday.
Despite specious evidenceof apermanentstructural change,aβ€œnew normal”,the relativelyhigh
levelsof unemploymentinactualityare nothingmore thana painfullyslow businesscycle. The analysis
done by Hobijnand Sahindiffersinthattheirfocusisa cross-countryanalysis asopposedtoa specific
trendanalysis, butcomplementsthisresearchwithrichhistoricdataand cross-countrycomparisons.
Althoughdemographicfactorsplaya large role inshiftingstructuresof employment;the coincidenceof
such a change duringthisbusinesscycle isnotseentobe the dominatingfactor. In the comingyearsthe
data suggesta returnto the β€œold normal”as labormarketinefficienciestaperfromthe market. In
practice,onlytime will tellwhetherthe recessionchange hasbeenpermanent, neverthelesscurrent
researchindicatesasanguine outlook.
Works Cited
1. Hobijn,B.,& Şahin,A. (2013). Beveridge Curve ShiftsacrossCountriessince the Great
Recession.IMFEconomicReview,61(4),566-600. doi:10.1057/imfer.2013.18
2. Diamond,P.(2013). Cyclical Unemployment,Structural Unemployment.IMFEconomicReview,
61(3), 410-455.
3. Data Source:FRED, Federal Reserve EconomicData,Federal Reserve Bankof St.Louis:Civilian
UnemploymentRate [UNRATE];U.S.Departmentof Labor:Bureau of Labor Statistics;
http://research.stlouisfed.org/fred2/series/UNRATE;accessed May1st
, 2014.
4. Data Source:FRED, Federal Reserve EconomicData,Federal Reserve Bankof St.Louis:Natural
UnemploymentRate [NROU] ;U.S. Congressional BudgetOffice;
http://research.stlouisfed.org/fred2/series/NROU;
5. Data Source:FRED, Federal Reserve EconomicData,Federal Reserve Bankof St.Louis:Job
Openings:Total Nonfarm[JTSJOR];U.S.Departmentof Labor:Bureauof Labor Statistics;
http://research.stlouisfed.org/fred2/series/JTSJOR;accessedMay1st, 2014.

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project

  • 1. β€œThe New Normal”: Structural vs.Cyclical U.S.Unemployment Econometrics II May 2, 2014 Joshua T. Rome
  • 2. One topicat the forefrontof U.S.economicdevelopmentoverthe pastseveral yearssince the financial crisishasbeenunemployment. The catalystof thisdiscourse isnomystery.Unemployment impactsmanyAmericansandthe relationshipwithGDPisempiricallyverifiable (thesocalledβ€œOkun’s law”). The mainquestionregardingthe persistentlyhigh levelsof unemployment iswhetherthishas beena structural or prolongedcyclical effect. Thispaperseekstounderstandthe recentchangesinthe unemploymentrate inthe contextof the previoussixtyyearsof unemploymentdatathatisavailable. The firstportionof the analysiswill be composedof lookingatthe patternof the unemploymentrate as a standalone time series. Followingasolidunderstanding of the historictrend;the unemploymentrate will be comparedwithtotal jobopeningsforfurthercluestothe nature of the recentunemployment levels. Analyzing the data The firststepin derivingarelationshipbetweenthissetof variablesistosimplyobserve the dataover time;andto analyze if there are any trends,seasonalityorotherdiscernible patterns. We beginbylookingat time graphs of our mainvariablesbeginning withunemployment. Aswithmany macroeconomictime series unemploymentisstronglytrended, showingcyclical peaksandtroughs, althoughvaryingindurationaswell asmagnitude. Itisclear thatlevel of unemploymenttodaystrongly dependsonthe level of unemploymentyesterday. If modeledasafirstorder autoregressivemodel: π‘ˆπ‘›π‘’π‘šπ‘π‘™π‘œπ‘¦π‘šπ‘’π‘›π‘‘ 𝑑 = 𝐡0 + 𝐡1 π‘ˆπ‘›π‘’π‘šπ‘π‘™π‘œπ‘¦π‘šπ‘’π‘›π‘‘ π‘‘βˆ’1 + πœ€ 𝑑
  • 3. The model appearsto be verysignificant,withthe overall level of significance of the F-Statistic at zero withanR-squaredof almost94%. Unfortunatelythesespurious resultsare anartifact of the high levelsof autocorrelation. Because ourmodel includesarighthandside dependentvariable any autocorrelationcausesestimatesof the regressiontobe inconsistentandinvalid;unfortunatelyaswell the Durbin-Watsonteststatisticwillnotbe validandcannotbe used. Thuswe will use Durbin’sβ€˜h’test whichisdesignedforexactlythissituation. We firstcompute the DurbinWatsonteststatistic: DW=.9878363 and from thisstatisticwe can backout our estimate for rho. 𝑃̂ = 1 βˆ’ π·π‘Š 2 andwe compute thisvalue tobe .50608185. β„Ž = π‘ƒΜ‚βˆš π‘›βˆ— (1βˆ’π‘›βˆ—)𝑆𝐸.𝐡̂ β„Ž = .51√ 256 (255).000240 = 32.715 > 2.56 thus we rejectthe null hypothesisthat there isno autocorrelationforthismodel specification. If apartial Correlogramis used, whichis basedon the partial autocorrelation functionintroducedbyBox-Jenkins,we canclearlysee thatthe firsttwolags of the model lie outside of the 95% confidence interval andthusare notrandom. The coefficientonthe original model alsomight
  • 4. seemtosuggesta unitroot as it isveryclose to one (.96); andthe dickeyfullertestfora unitroot would be appropriate totest forthis. The resultforthe dickeyfullertestwiththree laggedtermsandatrendis significantwithap-value of .0385; thuswe rejectthe null hypothesisof arandom-walk. The processof correctlyspecifyingthe model reliedonsimilarbutunrelatedintuition of how businesscycleswork. Inthe 1950’s manyeconomistsdescribedthe businesscycle intermsof alag on investmentdecisiondependingonthe growthof the economy. The resultingspecificationforthis phenomenonwasaβ€œsecondorderdifference equation”where the dependentvariable wasafunctionof the difference of the laggedfirstdifference of thatvariable. Ingeneral the systemcanresultin dampeningoranti-dampeningeffectsorstable peaksandtroughs;andof course applicable toother fields. Basedonthisintuitionthe model forunemploymentisestimated usingaportion of the sample (observations 1through50) witha laggedtermand a laggedfirstdifference term. π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ = 𝐡0 + 𝐡1 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘βˆ’1 + 𝐡2( π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘βˆ’1 βˆ’ π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘βˆ’2)+ πœ€ 𝑑 Thismodel isverysignificantwithlow RMSEwhichisgoodfor prediction. Generatingaprediction variable we cantestthe model we cantestthe model forthe remainingportionof the sample from
  • 5. 1962-2014. The resultsof this out-of-sampleforecastare verytightlyfitaroundthe actual datawitha meanresidual of .1621 as the difference betweenthe actual unemployment. There are twomainsourcesof uncertaintyregardingprediction;inthismodel aswell asany other. If the true valuesof all of the modelscoefficients wereknown;the rootmeansquarederror wouldbe the standarddeviationof the forecastwhichwe couldassume the errortermisnormally distributedaboutthe mean. Itisnot possible toknow the true value of the coefficients,becausefor each sample thatisdrawn;new coefficientswillbe estimated. Tocompute the variance of the estimate Var(Ρ”) we compute Var(𝑦 βˆ’ 𝑦̂) whichequalsVar(𝑦̂)+Var(y) –2Cov(𝑦̂, 𝑦). Mathematically;the implicationsof thismodel are numerous. Firstlythe modelimpliesalong- run unemploymentrate of 5% basedon the data. Thiscan easilybe shownby solvingforthe steady state where π‘₯ 𝑑 = π‘₯ π‘‘βˆ’1 = π‘₯ π‘‘βˆ’2 Thus: π‘₯βˆ— = .75 + .85π‘₯βˆ— + .55( π‘₯βˆ— βˆ’ π‘₯βˆ—) Resultingin: .15π‘₯βˆ— = .75 𝐷𝑖𝑣𝑖𝑑𝑒 𝑏𝑦 .15 β‡’ π‘₯βˆ— = 5 Thismodel wasestimated fromthe sample from 1950-1962, all other estimatesare out-of - sample forecasts;from whichwe observe thatthe model fitsthe datavery closely.
  • 6. Economicallythismaynotbe the mostgranularapproach to estimatinganequilibrium unemploymentlevel;butthe figure doesappeartobe reasonable. IndeedSt.LouisFederal reserve data estimatesNROUthe natural rate of unemploymentwithameanvalue of 5.55% anda value exactly equal to5% fromthe years2000-2009. A more accurate predictionof the longrunβ€œnatural”level of unemploymentshouldtake intoaccountdemographicsof the population. Anadditional implicationof thismodel specificationisthat the coefficientof the laggedfirstdifference at.55 is that the specification isunstable;butwithdampeningeffect. Inotherwordsany shocksto the systemwill resultinsmaller and smallerdifference fromthe steadystate level;the systemisdynamicallystable. For the nonmathematical non-statisticalreaderwhatwe learnfromthismodel isthe dependencyof the currentlevel of unemploymentonpreviouslevelsof unemployment. Predictionwith thismodel issomethingakintopredictingthe weather tomorrow bylookingoutthe window today; brightand sunnyandseventywe cansay withsome certaintythatit ishighlyunlikelytosnow.With unemploymentatagivenlevel we canmake similarobservations. Thismodel alsomakesanother implicitpredictionof alongrun rate of unemploymentof five percent,althoughthe accuracyof this predictioncanbe greatlyimprovedwithothereconomicdatasuchas populationdemographics. Nowthat we understandthe nature of the unemploymentdataovertime we shiftouranalysis towardsthe recenttrend. The unemploymentrate hadnot reachedheightsof levelsabove 8% since the 1980’s, and yearslateraftera recoveryinequitypricesthe unemploymentrate isstill atitshighestlevel 0 2 4 6 8 10 12 0 10 20 30 40 50 60 Thisdiagramillustratesthe dynamic stabilityof the model specifiedfrom the regression. The firstfew observationsare takenfromthe actual data;the restare the predictionsbasedonthe model. Randomshocksare exogenously introducedat32-38 and40 to illustrate the dynamicstability.
  • 7. inat leastone decade. Inorderto understandthistrendwe mustturnto the Beveridgecurve that relatesthe numberof nonfarmpayroll openingstothe unemploymentrate. In the figure we see the monthly dataof the two time seriesplottedagainsteachother fromthe yearsDec 2000- Mar 2014 formingthe so-calledBeveridgeCurve. Itappearsobviousthatthere isa structural differencebetweentwodifferenttime periods;visuallyone couldidentifytwolinesthatbest fitthe data. Basedon intuitionthere isadownwardsloping line whichwe specifyas (RestrictedModel): π½π‘œπ‘ π‘‰π‘Žπ‘π‘Žπ‘›π‘π‘¦ π‘…π‘Žπ‘‘π‘’π‘‘ = 𝛽0 + 𝛽1 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ + πœ€ 𝑑 Our coefficientof betaone isbelievedtobe negative; which the regressionconfirms. Inallowingthe slopeandcoefficient to be differentforthe twodifferentperiodswe definea categorical dummyvariable 𝑑𝑖 thatistrue for all periodsafterAugust2009. The specificationof the secondperiodmodel is: π½π‘œπ‘ π‘‰π‘Žπ‘π‘Žπ‘›π‘π‘¦ π‘…π‘Žπ‘‘π‘’π‘‘ = ∝0+∝1 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ + πœ€ 𝑑 In orderto create a more parsimoniousdefinitionof ourmodel inone equationwe mustdefinethe differencesbetweenthe twoseparate modelcoefficients: Let 𝛿1 =∝0βˆ’ 𝛽0 𝛿2 =∝1βˆ’ 𝛽1 The unrestricted model: π½π‘œπ‘ π‘‰π‘Žπ‘π‘Žπ‘›π‘π‘¦ π‘…π‘Žπ‘‘π‘’π‘‘ = 𝛽0 + 𝛽1 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ + 𝛿1 𝑑 𝑖 + 𝛿2 𝑑𝑖 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ + πœ€ 𝑑 Afterexecutingthe regressionof boththe restrictedandunrestrictedregressionswe are able to performa chowtestof structural difference. The null hypothesisisthatthe unrestrictedmodelis ∝0= 𝛽0 π‘Žπ‘›π‘‘ ∝1= 𝛽1while the alternative hypothesisisthatthe twoare in fact different. ChowTest ( π‘†π‘†πΈπ‘Ÿπ‘’π‘ π‘‘π‘Ÿπ‘–π‘π‘‘π‘’π‘‘βˆ’π‘†π‘†πΈ π‘’π‘›π‘Ÿπ‘’π‘ π‘‘π‘Ÿπ‘–π‘π‘‘π‘’π‘‘)βˆ— 1 π‘ž π‘…π‘’π‘ π‘‘π‘Ÿπ‘– 𝑐 𝑑𝑖 π‘œ 𝑛𝑠 𝑆𝑆𝐸 π‘’π‘›π‘Ÿπ‘’π‘ π‘‘π‘Ÿπ‘–π‘π‘‘π‘’π‘‘βˆ— 1 π‘›βˆ’π‘˜ = 3.098836765 0.025153714 = 123.19 > 4.605 The sum of squarederrorforthe unrestrictedmodelis 3.89882567, with155 denominatordegreesof freedom. The Restrictedsumof squarederroris 10.0964992 and the numberof restrictionsistwo
  • 8. correspondingtothe numeratordegreesof freedom. Giventhese degreesof freedomthe chow testwe can rejectthe null hypothesisthatthere isnostructural break at the 1% significance level. The cause generallyattributedtothe shiftinthe Beveridgecurve isincreasedfrictionsin matchingbetweenemployeesandemployers. Followingthe greatrecessionunemploymentbenefits were greatlyextendedtobeyondone year;impeding searchersfromincreasingtheireffort,thus decreasingmatchingefficiency. Structurallythe principallyaffectedindustryof the crisisfollowingthe housingboomhadbeenthe constructionindustry. Thisindustryhasrelatively lessfrictioninmatching compared to otherhigherskill industries thathave lesshirespervacancy suchas engineering. Inan article fromthe IMF EconomicReviewHobijnandSahinattribute muchof this shiftbetweenthese two factors1. Hobijn’sandSahin’sstudywasa longitudinal analysisof thirteencountriesoverfifteenyears. Interestingfindingsof theirresearch are thataside fromthe U.S. onlythree othercountriesexperienced a rightwardshiftinthe Beveridge curve: Portugal,Spain,andthe UnitedKingdom. (The othercountries analyzedinthe sample were Australia,Austria,Belgium, France,Germany,Japan,Netherlands,Norway and Switzerland.) Whatthese three countrieshadincommonwasa disproportionate decline in construction, acorollaryof the steepdeclinesinhousingprices. Inaddition,the researchwasputintoa historical perspectivewithBeveridgeshiftsof the 70’s and 80’s that had reversedtheirrightwardshift followingrecessions. The conclusionsof theiranalysis are thatthe rate of adjustmentof U.S.labor relative toothercountriesisveryhigh,andgiventhat unemploymentinsurance increasesare not permanent;the questioniswhenthiscyclical effectwill subside. Shiftingfocustothe latestiterationof the Beveridge Curve;althougharightwardshifthas occurredwhichis consistentwithβ€œstructural unemployment”,the curve appearstobe on a path back to itspreviousstructural levelslendingsupporttothe β€œprolongedcycle”argument. The observations are connectedintime anddecreasinginunemploymentwhilstincreasinginNonfarmjobopenings. This
  • 9. componentof the recenttrendiscyclical. But itis importanttonote that the trend isnot a straightline, nor convex asthe Beveridge Curve isgenerallyportrayed. Thisnonlinearstructure resemblinga downwardopeningparabolacanbe modeledby regressingnonfarmjobopenings onafirstorder β€˜UNRATE’ term witha squared β€˜UNRATE’ term. The coefficientof the squaredtermisexpectedtobe negative because the curve isdownwardopening,and giventhe tightbandof variationthe model is expectedtobe verystatisticallysignificantwithahighr-squared. Specification: π½π‘œπ‘ π‘‰π‘Žπ‘π‘Žπ‘›π‘π‘¦ π‘…π‘Žπ‘‘π‘’π‘‘ = 𝛽0 + 𝛽1 π‘ˆπ‘π‘…π΄π‘‡πΈπ‘‘ + 𝛽1 π‘ˆπ‘π‘…π΄π‘‡πΈ1 2 + πœ€ 𝑑 The regressionof the newmodel satisfiedall of the apriori assumptionsbut withone unique concern,a verystatisticallyinsignificantconstantterm. Afterconsiderationof the context;the unemploymentrate isrelativelyfarfromzeroconsideringthe spacingof the observationsandquantityof observations. In thiscontextthe lowsignificanceof the constanttermisunimportantandmerelyreflectsalarge distance fromthe y axisfromthe observations. Economically the empiricallyderivedcurve lendsevidence tothe prolongedbusinesscycle theoryregardingthe unemployment. Inthe contextof the previousBeveridge
  • 10. curve ex ante the greatrecession,the model predictsthatwe are on a path that leadstothe old structure of the Beveridge Curve. The currenttrendthuscan be decomposedintotwocomponents;a currentcyclical trendof reducedunemploymentandincreasedjobopenings,andaleftwardshifttothe olderlevelsof matchingefficiency. As extensionsof unemploymentinsurance are eliminatedandthe housingmarket recovers,higherturnoverpositionswill constitute alargercompositionof the overall USjob marketandlabor market efficiencywillslowlyreturn. Although the economyhasrecovered significantlysince the greatrecession,the recoveryhasbeenslow goingandiscontinuingtothisday. Despite specious evidenceof apermanentstructural change,aβ€œnew normal”,the relativelyhigh levelsof unemploymentinactualityare nothingmore thana painfullyslow businesscycle. The analysis done by Hobijnand Sahindiffersinthattheirfocusisa cross-countryanalysis asopposedtoa specific trendanalysis, butcomplementsthisresearchwithrichhistoricdataand cross-countrycomparisons. Althoughdemographicfactorsplaya large role inshiftingstructuresof employment;the coincidenceof such a change duringthisbusinesscycle isnotseentobe the dominatingfactor. In the comingyearsthe data suggesta returnto the β€œold normal”as labormarketinefficienciestaperfromthe market. In practice,onlytime will tellwhetherthe recessionchange hasbeenpermanent, neverthelesscurrent researchindicatesasanguine outlook.
  • 11. Works Cited 1. Hobijn,B.,& Şahin,A. (2013). Beveridge Curve ShiftsacrossCountriessince the Great Recession.IMFEconomicReview,61(4),566-600. doi:10.1057/imfer.2013.18 2. Diamond,P.(2013). Cyclical Unemployment,Structural Unemployment.IMFEconomicReview, 61(3), 410-455. 3. Data Source:FRED, Federal Reserve EconomicData,Federal Reserve Bankof St.Louis:Civilian UnemploymentRate [UNRATE];U.S.Departmentof Labor:Bureau of Labor Statistics; http://research.stlouisfed.org/fred2/series/UNRATE;accessed May1st , 2014. 4. Data Source:FRED, Federal Reserve EconomicData,Federal Reserve Bankof St.Louis:Natural UnemploymentRate [NROU] ;U.S. Congressional BudgetOffice; http://research.stlouisfed.org/fred2/series/NROU; 5. Data Source:FRED, Federal Reserve EconomicData,Federal Reserve Bankof St.Louis:Job Openings:Total Nonfarm[JTSJOR];U.S.Departmentof Labor:Bureauof Labor Statistics; http://research.stlouisfed.org/fred2/series/JTSJOR;accessedMay1st, 2014.