Test ID: 7440356
Multiple Regression and Issues in Regression Analysis 2
Question #1 of 106
QuestionID:461642ᅞ A)
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Questions #2-7 of 106
Consider the following analysis of variance (ANOVA) table:
Source Sum ofsquares Degreesoffreedom Meansquare
Regression 20 1 20
Error 80 40 2
Total 100 41
The F-statistic for the test of the fit of the model is closest to:
0.10.
10.00.
0.25.
Explanation
The F-statistic isequaltotheratioofthemeansquaredregressiontothemeansquarederror.
F = MSR/MSE = 20 / 2 = 10.
Ananalyst is interestedinforecasting the rate of employment growth andinstabilityfor254metropolitanareas around the
UnitedStates.The analyst's mainpurpose for these forecasts is to estimate the demandfor commercial real estate in each metro area.The independent variables inthe analysis representthe percentage of employmentin each industrygroup.
RegressionofEmployment GrowthRatesandEmploymentInstability
onIndustryMixVariablesfor254U.S.MetroAreas
Model1 Model2
Dependent Variable EmploymentGrowth RateRelative EmploymentInstability
Independent Variables
Coefficient
Estimate t-value
Coefficient
Estimate t-value
Intercept -2.3913 -0.713 3.4626 0.623 % Construction Employment 0.2219 4.491 0.1715 2.096
% Manufacturing Employment 0.0136 0.393 0.0037 0.064
Question #2 of 106
QuestionID:485606 Wholesale Trade Employment," and "% Retail Trade" only.ᅚ A)
ᅞ B)
ᅞ C)
Question #7 of 106
QuestionID:485611ᅞ A)
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Question #
8
of 106
QuestionID:4617560.0111 to 0.3319. 0.0897to0.2533. -0.0740to0.4170.
Explanation
With a sample size of254, and254 − 6 − 1 = 247degrees offreedom, the critical value fora two-tail 95% t-statistic is very
close to the two-tail 95% statistic of1.96. Using this critical value, the formulafor the 95% confidence interval for the jth coefficientestimateis:
95% confidenceinterval = .Butfirst weneedtofigureoutthe coefficientstandarderror:
Hence, the confidenceintervalis0.1715 ± 1.96(0.08182).
With 95% probability, the coefficient willrangefrom0.0111to0.3319, 95% CI = {0.0111 < b1 < 0.3319}. (StudySession3, LOS 9.f)
Onepossibleproblemthat could jeopardizethe validityoftheemploymentgrowth ratemodelismulticollinearity. Which ofthe
following would mostlikelysuggesttheexistenceofmulticollinearity? The Durbin-Watson statistic differs sufficiently from 2.
The F-statistic suggests that the overall regressionis significant, however the regression coefficients are not individually significant.
The varianceoftheobservations hasincreasedovertime.
Explanation
Onesymptomofmulticollinearityisthattheregression coefficientsmaynot beindividuallystatisticallysignificanteven when according to the F-statistic the overall regressionis significant.The problem ofmulticollinearityinvolves the existence of high correlation between two ormore independent variables.Clearly, as service employment rises, construction employment must
risetofacilitatethegrowth inthesesectors.Alternatively, asmanufacturingemploymentrises, theservicesectormustgrow to servethe broadermanufacturingsector.
The varianceofobservationssuggeststhepossibleexistenceof heteroskedasticity.
IftheDurbin-Watsonstatistic differssufficientlyfrom2, thisisasignthattheregressionerrors havesignificantserial correlation.
(StudySession3, LOS10.l)
MarySteen estimated that if she purchased shares of companies who announcedrestructuringplans at the announcement
and heldthemforfivedays, she wouldearnreturnsinexcessofthoseexpectedfromthemarketmodelof0.9%.These
returnsarestatisticallysignificantlydifferentfrom zero.Themodel wasestimated withouttransactions costs, andinreality
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Question #
9
of 106
QuestionID:461597ᅚ A)
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Questions #10-15 of 106
statistical significance,but not economic significance. statistical and economic significance.
amarketinefficiency.
Explanation
Theabnormalreturnsarenotsufficientto covertransactions costs, sothereisnoeconomic significancetothistrading strategy.This is not an example ofmarket inefficiency because excess returns are not available after covering transactions costs.
Seventy-twomonthlystock returnsforafund between1997and2002areregressedagainstthemarketreturn, measured by
the Wilshire 5000, and two dummy variables.The fund changedmanagers on January2, 2000.Dummy variable one is equal to 1if the returnis fromamonth between2000and2002.Dummy variable number two is equal to 1if the returnis from the second halfoftheyear.Thereare36observations whendummy variableoneequals0, halfof which are whendummy
variabletwoalsoequals zero.Thefollowingaretheestimated coefficient valuesandstandarderrorsofthe coefficients.
C
oefficient
Value
S
tandard
error
Mar
k
e
t
1.4
3000
0
.
3
1
9
000
D
u
mm
y
1
0
.
00
1
6
2
0
.
00067
5
D
u
mm
y
2
−
0
.
00
1
3
2
0
.
000733
Whatisthep-valueforatestofthe hypothesisthatthe betaofthefundisgreaterthan1?
Between 0.05 and 0.10. Lowerthan 0.01.
Between 0.01and 0.05.
Explanation
The betaismeasured bythe coefficientofthemarket variable.Thetestis whetherthe betaisgreaterthan1, not zero, sothe t-statistic isequalto (1.43 − 1) / 0.319 = 1.348, which isin betweenthet-values (with 72 − 3 − 1 = 68 degreesoffreedom)of 1.29 forap-valueof0.10and1.67forap-valueof0.05.
Autumn VoikuisattemptingtoforecastsalesforBrookfield Farms basedonamultipleregressionmodel. Voiku has constructedthefollowingmodel:
sa
l
es
= b + (b ×
C
P
I
)
+ (b ×
I
P
)
+ (b ×
GD
P
)
+ ε
Wh
ere
:
sa
l
es
= $ ch
an
g
e
in
sa
l
es
(
in
000
'
s
)
C
P
I
= ch
an
g
e
in
t
h
e
c
onsu
m
er
pri
c
e
inde
x
I
P = ch
an
g
e
in
indus
t
ria
l
produ
c
t
ion
(
m
i
ll
ions
)
GD
P = ch
an
g
e
in
GD
P (
m
i
ll
ions
)
A
ll
ch
an
g
es
in
v
aria
b
l
es
are
in
per
c
en
t
a
g
e
t
er
m
s.
Voikuusesmonthlydatafromtheprevious180monthsofsalesdataandfortheindependent variables.Themodelestimates (with coefficient standard errors inparentheses)are:
sales =10.2 + (4.6 × CPI) + (5.2 × IP) + (11.7 × GDP) (5.4) (3.5) (5.9) (6.8)
Thesumofsquarederrorsis140.3andthetotalsumofsquaresis368.7.
Voiku calculatestheunadjustedR, theadjustedR, andthestandarderrorofestimateto be0.592, 0.597, and0.910,
respectively.
Voikuis concernedthatoneormoreoftheassumptionsunderlyingmultipleregression has been violatedin heranalysis.Ina
conversation with DaveGrimbles, CFA, a colleague whois considered bymanyinthefirmto beaquantspecialist, Voikusays, "It is myunderstanding that there are five assumptions ofamultiple regressionmodel:"
Assumption1: Thereisalinearrelationship betweenthedependentandindependent variables.
Assumption2: The independent variables are not random, and there is zero correlation
betweenanytwooftheindependent variables.
Assumption3: Theresidualtermisnormallydistributed with anexpected valueof zero. Assumption4: Theresidualsareserially correlated.
Assumption5: The variance of the residuals is constant.
Grimblesagrees with Miller'sassessmentoftheassumptionsofmultipleregression.
Voiku tests andfails to reject each of the followingfournull hypotheses at the 99% confidence interval: Hypothesis 1: The coefficient onGDP is negative.
Hypothesis2: Theintercepttermisequalto-4.
Hypothesis3: A2.6% increaseintheCPI willresultinanincreaseinsalesofmorethan 12.0%.
Hypothesis 4: A1% increase inindustrial production will result ina1% decrease in sales.
Figure1:Partialtableofthe Student'st-distribution(One-tailedprobabilities)
df p
=
0
.1
0
p
=
0
.
0
5 p
=
0
.
0
25 p
=
0
.
0
1 p
=
0
.
00
5
1
70
1.2
8
7
1.
6
54
1.
9
7
4
2.
3
4
8
2.
60
5
1
76
1.2
8
6
1.
6
54
1.
9
7
4
2.
3
4
8
2.
60
4
1
8
0
1.2
8
6
1.
6
5
3
1.
9
73
2.
3
4
7
2.
603
Figure
2:
Partial
F-
T
able
critical
v
alues
for
right-hand
tail
area
e
q
ual
to
0
.
0
5
df1
=
1 df1
=
3
df1
=
5
df2
=
1
70
3
.
9
0
2.
66
2.2
7
Question #15 of 106
QuestionID:461569Partial
Results
fro
m
Regression
ARAR
on
S
ize
and
Extent
of
Indexing
Question #23 of 106
QuestionID:461526ᅚ A)
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Question #24 of 106
QuestionID:461749ᅞ A)
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Question #25 of 106
QuestionID:461591independent variablesarenotrandomandnoexactlinearrelationshipexists betweenthetwoormoreindependent variables, errortermisnormallydistributed with anexpected valueof zeroand constant variance, andtheerrortermisserially
uncorrelated. (StudySession3, LOS10.f)
Considerthefollowingregressionequation: Sales= 20.5 + 1.5R&D + 2.5ADV -3.0COMP
wh
ere
S
a
l
es
is
do
ll
ar
sa
l
es
in
m
i
ll
ions
,
R
&
D
is
resear
ch
and
de
v
e
l
op
m
en
t
e
x
pendi
t
ures
in
m
i
ll
ions
,
A
D
V
is
do
ll
ar
a
m
oun
t
spen
t
on
ad
v
er
t
isin
g
in
m
i
ll
ions
,
and
C
O
M
P
is
t
h
e
nu
m
b
er
of
c
o
m
pe
t
i
t
ors
in
t
h
e
indus
t
ry.
Which of the followingis NOTa correct interpretation of this regressioninformation?
If a company spends $1 more on R&D (holding everything else constant), sales are expected to increase by $1.5 million.
IfR&Dandadvertising expenditures are $1million each and there are 5 competitors,
expectedsalesare $9.5million.
One more competitor will mean $3million less in sales (holding everything else constant).
Explanation
Ifa company spends $1 millionmore onR&D (holding everything else constant), sales are expected to increase by $1.5
million.Always beawareoftheunitsofmeasureforthedifferent variables.
When constructingaregressionmodel to predict portfolio returns, ananalyst runs aregressionfor the past five yearperiod. After examining the results, she determines that anincrease ininterest rates two years ago hada significant impact on portfolioresultsforthetimeoftheincreaseuntilthepresent.Byperformingaregressionovertwoseparatetimeperiods, the
analyst would beattemptingtoprevent which typeofmisspecification?
Using a lagged dependent variable as an independent variable. Forecasting the past.
Incorrectlypoolingdata.
Explanation
Therelationship betweenreturnsandthedependent variables can changeovertime, soitis criticalthatthedata bepooled
correctly.Runningtheregressionformultiplesub-periods (inthis casetwo)ratherthanonetimeperiod canproducemore
accurate results.
Questions #27-32 of 106
RegressionofOperatingProfitonPopulation,OperatingHours,and
Question #31 of 106
QuestionID:485596ᅚ A)
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Question #32 of 106
QuestionID:485597ᅞ A)
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Questions #33-3
8
of 106
(LOS10.c)The standarddeviation ofregressionresiduals is closest to:
15.47
0.42
239.42
Explanation
SSE = SST-RSS = 10,898 -6,349 = 4,549
MSE = SSE/(n-k-1) = 4,549/19 = 239.42
SEE = (MSE) = 15.47
t= beta- beta /S = 6.767-5 /2.56 = 0.69. Wefailtorejectthenull hypothesis.
(LOS10.i)
The operatingprofit model as specifiedis mostlikelya:
Time series regression Cross-sectional regression Autoregressivemodel
Explanation
Cross-sectionaldatainvolvemanyobservationsforthesametimeperiod.Time-seriesdatausesmanyobservationsfrom
different time periods for the same entity.
(LOS10.a)
DaveTurnerisasecurityanalyst whoisusingregressionanalysistodetermine how welltwofactorsexplainreturnsfor
commonstocks.Theindependent variablesarethenaturallogarithmofthenumberofanalystsfollowingthe companies, Ln(no.ofanalysts), andthenaturallogarithmofthemarket valueofthe companies, Ln(market value).Theregressionoutput generatedfroma statistical programis givenin the following tables. Each p-value corresponds to a two-tail test.
Turnerplanstousetheresultintheanalysisoftwoinvestments. WLK Corp. hastwelveanalystsfollowingitandamarket capitalization of $2.33 billion. NGRCorp. has two analysts followingit andamarket capitalization of $47million.
Table 1: Regression Output
Variable CoefficientStandardErroroftheCoefficient t-statistic p-value
Intercept 0.043 0.01159 3.71 < 0.001
Ln(No. ofAnalysts) −0.027 0.00466 −5.80 < 0.001 0.5
Question #3
9
of 106
QuestionID:461755ᅞ A)
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Question #40 of 106
QuestionID:461700ᅞ A)
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Questions #41-46 of 106
Multicollinearityoccurs whenthereisa high correlationamongindependent variablesandmayexistifthereisasignificant F
-statistic forthefitoftheregressionmodel, butatleastoneinsignificantindependent variable when weexpectallofthemto be significant.In this case the coefficient onln(market value) wasnot significant at the1% level, but the F-statistic wassignificant. It wouldmakesense that thesizeof thefirm, i.e., themarket value, and thenumberofanalysts would bepositively correlated.
(StudySession3, LOS10.l)
Which of thefollowingis NOTamodel that hasaqualitativedependent variable?
Discriminant analysis. Logit.
Eventstudy.
Explanation
Aneventstudyistheestimationoftheabnormalreturns--generallyassociated with aninformationalevent-thattakeon quantitative values.
Which ofthefollowingstatementsregarding heteroskedasticityisleastaccurate?
Multicollinearity is a potential problem only in multiple regressions, not simple regressions.
Heteroskedasticityonlyoccursin cross-sectionalregressions.
Thepresenceof heteroskedastic errortermsresultsina varianceoftheresidualsthat
istoolarge.
Explanation
Ifthereareshiftingregimesinatime-series (e.g., changeinregulation, economic environment), itispossibleto have
heteroskedasticityina time-series.
JohnRains, CFA, isaprofessoroffinanceatalargeuniversitylocatedinthe Eastern UnitedStates. Heisactivelyinvolved
with hislocal chapteroftheSocietyof FinancialAnalysts.Recently, he wasaskedtoteach onesessionofaSociety-sponsored
CFAreview course, specifically teaching the classaddressing the topic ofquantitativeanalysis.Basedupon hisfamiliarity with theCFAexam, hedecides that thefirst part of thesessionshould beareview of the basic elementsofquantitativeanalysis,
such as hypothesistesting, regressionandmultipleregressionanalysis. He wouldliketodevotethesecond halfofthereview
sessiontothepracticalapplicationofthetopics he coveredinthefirst half.
Rainsdecidesto constructasampleregressionanalysis casestudyfor hisstudentsinordertodemonstratea"real-life"
applicationofthe concepts. He begins by compilingfinancialinformationonafictitious company calledBigRig, Inc.According
ᅞ B)
ᅚ C)
Question #4
9
of 106
QuestionID:461752ᅚ A)
ᅞ B)
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Question #50 of 106
QuestionID:461609ᅞ A)
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0.20
5.00
Explanation
The F-statistic isequal to theratioof themeansquaredregression to themeansquarederror.
F = MSR / MSE = 20 / 4 = 5.
Ananalystis buildingaregressionmodel which returnsaqualitativedependant variable basedonaprobabilitydistribution.
Thisisleastlikelya:
discriminant model.
probit model.
logitmodel.
Explanation
Aprobitmodelisaqualitativedependant variable which is basedonanormaldistribution.Alogitmodelisaqualitative
dependant variable which is basedonthelogistic distribution.Adiscriminantmodelreturnsaqualitativedependant variable
basedonalinearrelationship that can beusedforrankingor classificationintodiscretestates.
WandaBrunner, CFA, istryingto calculatea 98% confidenceinterval (df = 40)foraregressionequation basedonthe
followinginformation:
C
oefficient
Standard
E
rror
In
t
er
c
ep
t
-10.60
%
1.357
DR
0.52
0.023
C
S
0.32
0.025
Which ofthefollowingare closesttothelowerandupper boundsfor variableCS?
0.274 to 0.367.
0.267to0.374.
0.260 to0.381.
Explanation
The critical t-valueis2.42at the 98% confidencelevel (two tailed test).Theestimatedslope coefficient is0.32and the
Question #56 of 106
QuestionID:485617ᅞ A)
ᅞ B)
ᅚ C)
Question #57 of 106
QuestionID:485618ᅚ A)
ᅞ B)
ᅞ C)
Question #5
8
of 106
QuestionID:461698Explanation
The coefficient ofdeterminationis thestatistic used toidentifyexplanatorypower.This can be calculatedfrom theANOVA
tableas3.896/6.327 x 100 = 61.58%.
Theresidualstandarderrorof0.3indicates that thestandarddeviationof theresidualsis0.3million housingstarts. Without
knowledgeof thedatafor thedependent variableit isnot possible toassess whether thisisasmalloralargeerror.
The F statistic doesnot enableus to concludeon both independent variables.It onlyallowsus thereject the hypothesis that all
regression coefficientsare zeroandaccept the hypothesis that at least oneisn't.
(StudySession3, LOS10.g)
Theestimatedstandarddeviationof housingstarts (inmillions)isclosestto:
0.3
0.22
0.47
Explanation
Housingstartsis thedependent variable.
Varianceofdependent variable = SST/(n-1) = 6.327/29 = 0.22
Standarddeviation = (0.22) = 0.467
(StudySession3, LOS 9.j)
Which of thefollowingis theleast appropriatestatement inrelation toR-squareandadjustedR-square:
Adjusted R-square is a value between 0 and 1 and can be interpreted as a percentage
AdjustedR-squaredecreases when theaddedindependent variableaddslittle value
totheregressionmodel
R-squaretypicallyincreases whennew independent variablesareaddedtothe
regressionregardlessof theirexplanatorypower
Explanation
AdjustedR-square can benegativeforalargenumberofindependent variables that havenoexplanatorypower.Theother
twostatementsare correct.
(StudySession3, LOS10.h)
ᅞ A) regression. However, the analyst uses returns of portfolios of stocks instead of individual stocks in the regression. Which of the following
ᅞ C)
Question #61 of 106
QuestionID:461592ᅚ A)
ᅞ B)
ᅞ C)
Question #62 of 106
QuestionID:461674ᅚ A)
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Questions #63-6
8
of 106
willincreasethepowerofthetest bygivingtheteststatistic moredegreesoffreedom.
Explanation
Theuseofportfoliosreducesthestandarddeviationofthereturns, which reducesthestandarddeviationoftheresiduals.
DavidBlack wants to test whether theestimated betainamarket modelisequal toone. He collectedasampleof60monthly
returnsonastock andestimatedtheregressionofthestock'sreturnsagainstthoseofthemarket.Theestimated beta was
1.1, andthestandarderrorofthe coefficientisequalto0.4. WhatshouldBlack concluderegardingthe betaif heusesa5%
levelofsignificance? Thenull hypothesis that betais:
equal to one cannot be rejected.
equal tooneisrejected.
notequaltoone cannot berejected.
Explanation
The calculatedt-statistic ist = (1.1 − 1.0) / 0.4 = 0.25.The criticalt-valuefor (60 − 2) = 58 degreesoffreedomisapproximately
2.0.Therefore, thenull hypothesis that betaisequal toone cannot berejected.
Supposetheanalyst wantstoaddadummy variablefor whetheraperson hasanundergraduate collegedegreeanda
graduatedegree. WhatistheCORRECTrepresentationifaperson has both degrees?
UndergraduateDegree
Dummy Variable
GraduateDegree
Dummy Variable
1 1
0 1
0 0
Explanation
Assigninga zeroto both categoriesisappropriateforsomeone with neitherdegree.Assigningonetotheundergraduate
categoryand zero to thegraduate categoryisappropriateforsomeone with onlyanundergraduatedegree.Assigning zero to
theundergraduate categoryandone to thegraduate categoryisappropriateforsomeone with onlyagraduatedegree.
Assigningaoneto both categoriesis correctsinceitreflectsthepossessionof both degrees.
VikasRathod, anenrolled candidatefor theCFA LevelIIexamination, hasdecided toperforma calendar test toexamine
Question #63 of 106
QuestionID:485648ᅞ A)
ᅚ B)
ᅞ C)
Question #64 of 106
QuestionID:485649ᅞ A)
ᅚ B)
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Question #65 of 106
QuestionID:485650daysofthe week.Asaproxyfor blue-chips, he hasdecidedtousetheS&P 500index.Theanalysis willinvolvetheuseof
dummy variablesandis basedonthepast780tradingdays. Hereareselectedfindingsof hisstudy:
RSS 0.0039
SSE 0.9534
SST 0.9573
R-squared 0.004
SEE 0.035
Jessica Jones, CFA, afriendofRathod, overhearsthat heisinterestedinregressionanalysisand warns himthat whenever
heteroskedasticityispresentinmultipleregressionthis couldunderminetheregressionresults.Shementionsthatoneeasy
way tospot conditional heteroskedasticityis through ascatterplot, but sheadds that thereisamoreformal test.
Unfortunately, she can't quiterememberitsname. Jessica believes that heteroskedasticity can berectifiedusing Whit
e-correctedstandarderrors. Herson Jonathan who hasalsotakenpartinthediscussion, hearsthis commentandarguesthat
White correction wouldtypicallyreducethenumberofTypeIerrorsinfinancialdata.
How manydummy variablesshouldRathoduse?
Five Four Six
Explanation
Thereare5 tradingdaysina week, but weshoulduse (n − 1)or4dummiesinorder toensureno violationsofregression
analysisoccur.
(StudySession3, LOS10.j)
Whatismostlikelyrepresented bytheinterceptoftheregression?
The intercept is not a driver of returns, only the independent variables
Thereturnonaparticulartradingday
Thedrift ofarandom walk
Explanation
Theomitted variableisrepresented by theintercept.So, if we havefour variables torepresent Monday through Thursday, the
intercept wouldrepresentreturnson Friday.
(StudySession3, LOS10.j)
Questions #71-76 of 106
R = RSS / SST = 100 / 400 = 0.25
The F-statistic isequaltotheratioofthemeansquaredregressiontothemeansquarederror.
F = 100 / 7.5 = 13.333
Damon Washburn, CFA, is currentlyenrolledasapart-timegraduatestudentatState University. Oneof hisrecent
assignmentsfor his courseonQuantitativeAnalysisis toperformaregressionanalysisutilizing the concepts coveredduring
thesemester. Hemust interpret theresultsof theregressionas wellas the test statistics. Washburnis confident in hisability to
calculate thestatistics because the classisallowed tousestatisticalsoftware. However, herealizes that theinterpretationof
thestatistics will bethetruetestof his knowledgeofregressionanalysis. Hisprofessor hasgiventothestudentsalistof
questionsthatmust beanswered bytheresultsoftheanalysis.
Washburn hasestimatedaregressionequationin which 160quarterlyreturnsontheS&P 500areexplained bythree
macroeconomic variables:employmentgrowth (EMP)asmeasured bynonfarmpayrolls, grossdomestic product (GDP)
growth, andprivateinvestment (INV).Theresultsof theregressionanalysisareasfollows:
CoefficientEstimates
Parameter Coefficient StandardError
ofCoefficient
Intercept 9.50 3.40
EMP -4.50 1.25
GDP 4.20 0.76
INV -0.30 0.16
OtherData:
Regressionsumofsquares (RSS) = 126.00
Sumofsquarederrors (SSE) = 267.00
Durbin-Watsonstatistic (DW) = 1.34
Abbre
v
iated
T
able
of
the
S
tudent's
t-distribution
(One-
T
ailed
Probabilities
)
df p=0.10 p=0.05 p=0.025 p=0.01 p=0.005
3 1.638 2.353 3.182 4.541 5.841
10 1.372 1.812 2.228 2.764 3.169
50 1.299 1.676 2.009 2.403 2.678
100 1.290 1.660 1.984 2.364 2.626
120 1.289 1.658 1.980 2.358 2.617
200 1.286 1.653 1.972 2.345 2.601
C
ritical
Values
for
D
urbin-
W
atson
S
tatistic
(
α
=
0
.
0
5
)
K=1 K=2 K=3 K=4 K=5
n d d d d d d d d d d
2
ᅚ A)
no significant positive serial correlation in the residuals.
Question #77 of 106
QuestionID:461741ᅞ A)
ᅚ B)
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Question #7
8
of 106
QuestionID:461701ᅞ A)
ᅞ B)
ᅚ C)
Question #7
9
of 106
QuestionID:461594Explanation
Thestandarderrorof theestimateisequal to [SSE/(n − k − 1)] = [267.00/156] = approximately1.31. (StudySession3,
LOS 9.j)
An analyst is testing to see whether a dependent variable is related to three independent variables. He finds thattwo of the independent
variables are correlated with each other, butthatthe correlation is spurious. Which of the following is most accurate? There is:
no evidence of multicollinearity and serial correlation.
evidenceofmulticollinearity butnotserial correlation.
evidence of multicollinearity and serial correlation.
Explanation
Just because the correlation is spurious, does not mean the problem of multicollinearity will go away. However, there is no evidence of
serial correlation.
Which of thefollowingisleastlikelyamethodused todetect heteroskedasticity?
Test of the variances.
Breusch-Pagantest.
Durbin-Watsontest.
Explanation
TheDurbin-Watson test isused todetect serial correlation.TheBreusch-Pagan test isused todetect heteroskedasticity.
63monthlystock returnsforafund between1997and2002areregressedagainstthemarketreturn, measured bythe
Wilshire5000, andtwodummy variables.Thefund changedmanagerson January2, 2000.Dummy variableoneisequalto1
if thereturnisfromamonth between2000and2002.Dummy variablenumber twoisequal to1if thereturnisfrom the
second halfof theyear.Thereare36observations whendummy variableoneequals0, halfof which are whendummy
variabletwoalsoequals0.Thefollowingaretheestimated coefficient valuesandstandarderrorsofthe coefficients.
C
oefficient Value
S
tandard
error
Mar
k
e
t
1.43000
0.31
9
000
Du
mm
y
1 0.00162
0.000675
Du
mm
y
2 0.00132
0.000733
ᅞ A)
ᅚ B)
ᅞ C)
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8
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QuestionID:461746ᅞ A)
ᅚ B)
ᅞ C)
Question #
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QuestionID:461757ᅞ A)
ᅚ B)
ᅞ C)
Whatisthep-valueforatestofthe hypothesisthatperformanceinthesecond halfoftheyearisdifferentthanperformancein
thefirst halfoftheyear?
Lower than 0.01.
Between0.05and0.10.
Between0.01and0.05.
Explanation
Thedifference betweenperformancein thesecondandfirst halfof theyearismeasured bydummy variable2.Thet-statistic
isequalto0.00132 / 0.000733 = 1.800, which is betweenthet-values (with 63 − 3 − 1 = 59 degreesoffreedom)of1.671fora
p-valueof0.10, and2.00forap-valueof0.05 (notethatthetestisatwo-sidedtest).
When twoormoreof theindependent variablesinamultipleregressionare correlated with each other, the conditionis called:
conditional heteroskedasticity. multicollinearity.
serial correlation.
Explanation
Multicollinearityrefers to the condition when twoormoreof theindependent variables, orlinear combinationsof the
independent variables, inamultipleregressionare highly correlated with each other.This conditiondistorts thestandarderror
ofestimateandthe coefficientstandarderrors, leadingtoproblems when conductingt-testsforstatisticalsignificanceof
parameters.
Ananalyst hasrunseveralregressions hoping topredict stock returns, and wants to translate thisintoaneconomic
interpretationfor his clients.
Return = 0.03 + 0.020Beta-0.0001MarketCap (in billions) + ε
A correctinterpretationoftheregression mostlikelyincludes:
prediction errors are always on the positive side.
a billiondollarincreaseinmarket capitalization willdrivereturnsdown by0.01%. astock with zero betaand zeromarket capitalization willreturnprecisely3.0%.
Explanation
The coefficientofMarketCapis0.01%, indicatingthatlarger companies haveslightlysmallerreturns. Notethata company
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QuestionID:461607ᅚ A)
ᅞ B)
ᅞ C)
Question #
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QuestionID:461645ᅚ A)
ᅞ B)
ᅞ C)
Questions #
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4-
89
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Consider thefollowingestimatedregressionequation, with calculatedt-statisticsof theestimatesasindicated:
A
U
T
O =
10.0
+
1.25
P
I
+
1.0
T
EEN
-
2.0
I
N
S
with a PI calculated t-statstic of 0.45, a TEEN calculated t-statstic of 2.2, and an INS calculated t-statstic of 0.63.
The equation was estimated over 40 companies. The predicted value of AUTO if PI is 4, TEEN is 0.30, and INS = 0.6 is closest to:
14.10.
14.90.
17.50.
Explanation
PredictedAUTO = 10 + 1.25 (4) + 1.0 (0.30)-2.0 (0.6)
= 10 + 5 + 0.3-1.2
= 14.10
An analyst runs a regression of monthly value-stock returns on five independent variables over 48 months. The total sum of squares is 430, and the sum of squared errors is 170. Testthe null hypothesis atthe 2.5% and 5% significance level that all five of the independent
variablesareequalto zero.
Rejected at 2.5% significance and 5% significance.
Rejected at 5% significance only.
Not rejected at 2.5% or 5.0% significance.
Explanation
The F-statistic is equal to the ratio of the mean squared regression (MSR) to the mean squared error (MSE).
RSS = SST - SSE = 430 - 170 = 260
MSR = 260 / 5 = 52
MSE = 170 / (48 - 5 - 1) = 4.05
F = 52 / 4.05 = 12.84
The critical F-valuefor5and42degreesoffreedomata5% significancelevelisapproximately2.44.The critical F-valuefor5and42
degrees of freedom at a 2.5% significance level is approximately 2.89. Therefore, we can rejectthe null hypothesis at either level of
significance and conclude that at least one of the five independent variables explains a significant portion of the variation of the dependent
variable.
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QuestionID:485641 be responsible for providing research on the airline industry. Pinnacle Airlines, a leader in the industry, represents a large holding in Smith Brothers' portfolio. Looking back overpastresearch on Pinnacle, Carterrecognizesthatthe company historically has beenastrongperformer in what is considered to be a very competitive industry. The stock price over the last 52-week period has outperformed that of
other industry leaders, although Pinnacle's net income has remained flat. Carter wonders if the stock price of Pinnacle has become
overvalued relative to its peer group in the market, and wants to determine if the timing is right for Smith Brothers to decrease its position in Pinnacle.
Carter decides to run a regression analysis, using the monthly returns of Pinnacle stock as the dependent variable and monthly returns of
the airlines industry as the independent variable.
Analysis
of
Variance
T
able
(A
N
OVA
)
Which of the following is least likely to be an assumption regarding linear regression?
The variance of the residuals is constant.
A linear relationship exists between the dependent and independent variables.
Theindependent variableis correlated with theresiduals.
Explanation
Although the linear regression model is fairly insensitive to minor deviations from any of these assumptions, the independent variable is
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QuestionID:485643Based upon her analysis, Carter has derived the following regression equation: Ŷ = 1.75 + 3.25X. The predicted value of the Y variable equals50.50, ifthe:
coefficient of the determination equals 15.
predicted value of the dependent variable equals 15.
predicted value of the independent variable equals 15.
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QuestionID:485646Point 1: Data derived from regression analysis may be homoskedastic.
Point 2: Data from regression relationships tends to exhibit parameter instability. Point 3: Results of regression analysis may exhibit autocorrelation.
Question #
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1 of 106
QuestionID:461678ᅞ A)
ᅞ B)
ᅚ C)
Mul
t
iple
R
0.
8
170
88
R
0.667632
Ad
j
us
t
ed
R
0.617777
S
t
andard
E
rror 1.655
89
1
Ob
ser
v
a
t
ions
24
A
N
OVA
df
SS
M
S
Regression 3 110.156
8
36.71
89
5
Residual
20 54.
8
3
9
5 2.741
9
75
To
t
al
23 164.
99
63
C
oefficients
S
tandard
E
rror
t-
S
tatistic
In
t
er
c
ep
t
-0.23
8
21
0.3
88
717
-0.612
8
2
J
anuary
2.560552
1.232634
2.077301
S
m
all
Cap
Inde
x
0.23134
9
0.123007
1.
88
077
8
L
arge
Cap
Inde
x
0.
9
51515
0.25452
8
3.73
8
35
9
Gloucester willperformanF-testfortheequation. Healsoplanstotestforserial correlationand conditionalandunconditional
heteroskedasticity.
JasonBrown, CFA, isinterestedinGloucester'sresults. Hespeculatesthattheyareeconomicallysignificantinthatexcessreturns could be earned by shorting the large capitalization and the small capitalization indexes in the month of January and using the proceeds to buy
the fund.
The percent of the variation in the fund's return that is explained by the regression is:
61.78%.
81.71%.
66.76%.
Explanation
The R tells us how much of the change in the dependent variable is explained by the changes in the independent variables in the
regression: 0.667632.
2
2
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QuestionID:461679of the CFA curriculum, and unconditional heteroskedasticity is generally considered less serious than conditional heteroskedasticity.
Question #
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QuestionID:461683The index fund regression should provide a higher R than the active manager regression. R is the sum of squares regression divided by
the total sum of squares.
The equation was estimated over 40 companies. Using a 5% level of significance, which of the estimated coefficients are significantly
Question #
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of 106
QuestionID:461644ᅞ A)
ᅚ B)
ᅞ C)
Question #100 of 106
QuestionID:461675The critical t-values for 40-4-1 = 35 degrees of freedom and a 5% level of significance are ± 2.03.
The calculated t-values are:
tforR&D = 1.25 / 0.45 = 2.777
tforADV = 1.0/ 2.2 = 0.455
t for COMP = -2.0 / 0.63 = -3.175
t for CAP = 8.0 / 2.5 = 3.2
Therefore, R&D, COMP, and CAP are statistically significant.
A dependent variable is regressed againstthree independent variables across 25 observations. The regression sum of squares is 119.25,
and the total sum of squares is 294.45. The following are the estimated coefficient values and standard errors of the coefficients.
Coefficient ValueStandard error
1 2.43 1.4200
2 3.21 1.5500
3 0.18 0.0818
What is the p-value for the test of the hypothesis that all three of the coefficients are equal to zero?
Between 0.05 and 0.10.
lower than 0.025.
Between 0.025 and 0.05.
Explanation
This test requires an F-statistic, which is equal to the ratio of the mean regression sum of squares to the mean squared error.
The mean regression sum of squares is the regression sum of squares divided by the number of independent variables, which is 119.25 /
3 = 39.75.
The residual sum of squares is the difference between the total sum of squares and the regression sum of squares, which is 294.45 −
119.25 = 175.20. The denominator degrees of freedom is the number of observations minus the number of independent variables, minus 1, which is 25 − 3 − 1 = 21. The mean squared error is the residual sum of squares divided by the denominator degrees of freedom, which is 175.20 / 21 = 8.34.
The F-statistic is 39.75 / 8.34 = 4.76, which is higher than the F-value (with 3 numerator degrees of freedom and 21 denominator degrees offreedom)of3.07atthe5% levelofsignificanceand higherthanthe F-valueof3.82atthe2.5% levelofsignificance.The conclusionis
thatthep-valuemust belowerthan0.025.
Rememberthep-valueistheprobabilitythatliesabovethe computedteststatistic foruppertailtestsor below the computedteststatistic
ᅚ A) possible. We should have used only two dummy variables. Multicollinearity is a problem in this case. Specifically, a linear combination of independent variablesisperfectly correlated. X1 + X2 + X3 = 1.
There are too many dummy variables specified, so the equation will suffer from multicollinearity.
The management of a large restaurant chain believes that revenue growth is dependent upon the month of the year. Using a standard 12
Alex Wade, CFA, is analyzing the result of a regression analysis comparing the performance of gold stocks versus a broad equity market
Question #103 of 106
QuestionID:461540Jacob Warner, CFA, is evaluating a regression analysis recently published in a trade journal that hypothesizes thatthe annual performance of the S&P 500 stock index can be explained by movements in the Federal Funds rate and the U.S. Producer Price Index (PPI). Which ofthefollowingstatementsregarding hisanalysisis mostaccurate?
The p-value is the smallest level of significance for which the null hypothesis can be rejected. Therefore, for any given variable, if the p-value of a variable is less than the significance level, the null hypothesis can be rejected and the variable is considered to be statistically significant.
An analyst is estimating a regression equation with three independent variables, and calculates the R, the adjusted R, and the
F-statistic. The analystthen decides to add a fourth variable to the equation. Which of the following is most accurate?
The R and F-statistic will be higher, but the adjusted R could be higher or lower.
TheadjustedR will be higher, buttheR and F-statistic could be higherorlower.
The R will be higher, butthe adjusted R and F-statistic could be higher or lower.
Explanation
ᅞ C)
Question #106 of 106
QuestionID:461742ᅞ A)
ᅚ B)
ᅞ C)
Take first differences of the dependent variable.
Explanation
Thefirstdifferencingisnotaremedyforthe collinearity, noristheinclusionofdummy variables.The bestpotentialremedyistoattempt
to eliminate highly correlated variables.
A variable is regressed againstthree other variables, x, y, and z. Which of the following would NOT be an indication of multicollinearity? X is closelyrelatedto:
3.
y .
3y + 2z.
Explanation
If x is related to y, the relationship between x and y is not linear, so multicollinearity does not exist. If x is equal to a constant (3), it will be correlated with theinterceptterm.
2