Cấc nhấn tó ảnh hưởng đén thời gian thi cổng các dự án xầy dựng bằng multiple linear regression (mlr) (identifying the factors influencing to the construction time of construction projects by multiple linear regression mlr)

T Phan tich chu6i gia ttj lua g�o t�i tinh Tra Vinh, D6ng B1ng Song Citu Long .: Cac ye'u t6 tac dQng de'n tinh tr�ng ngheo ciia hQ gia dlnh d Nong Thon Nghien cuu trltong h�p tinh Bl

DANH sAcH THANH VIEN THAM GIA NGHIEN cUU DE TAI

VA BON VI PHOI HOP CI-IiNH

1 TS Luu Truong Van, Truong Khoa Xay Dgng & Di�n, D�i hQC Mo TP HCM

2 Th.S Ph�m Chi Cong, Cong ty TNHH XD & TM Kim Cuong

Khoa Xay Dgng va Di�n, D�i hQc Mo TP.HCM

,

Ml)C Ll)C

10

1.1 Gioi thi�u chung : 10

I 2 M \lC t1eu ng 1en cuu , 1 O ·� h·� ' 1.3 Phuong phap nghien cuu 11

1.4 Ph� vi nghien cuu: 11

CHU'ONG 2 CO SO LY THUYET 12 2.1 Ti€n d9 xay dvng: , 12

2.2 Ly thuy€t bang cau hoi: 12

2.2.1 Gioi thi�u: 12

2.2.2 Mdu nghien cuu: � 13

2.3 Khai quat v€ phan tich h6i quy 13

2.3.1 H6i quy tuy�n tinh don � , 13

2 3 1.1 Cac gia dinh d6i �6i phan tich hf>i quy tuy€9 tinh don 14

2.3.1.2 B9 chinh xac khi uoc luqng cac tham s6 cua t6ng th€ ti:r cac h� s6 h6i quy cua mdu - 15

2.3 1.3 Banh gia d9 phu hQ'p cua mo hinh :: 15

2.3.1.4 Kiem dinh cac gia thuy€t ' 17

2.3 1.5 Dv doan b�ng mo hinh hf>i quy: 17

2.3.1.6 Chuftn doan S\l' vi phi;tm cac gia dinh cdn thiet trong hf>i quy tuyen tinh 18

2.3.2 Hf>i quy tuyen tinh b{,i: 19

2.3.2.1 Banh gia d9 phu hqp cua mo hinh h6i quy tuy€n tinh b{>i 20

� ' 2.3.2.2 Bo luoRg da c{,ng tuyen: 20

CHU'ONG 3: PHU'ONG TRINH BTC 22 3 I Phuang trinh BTC (m6i quan h� thoi gian va chi phi) 22

3.2 Cac y€u t6 anh hucmg d€n ti€n d9 dv an: 23

MVCLVC

5.1 Ket lu�n 59

5.2 Kha nang (mg d\mg va y nghia cua nghien cuu 60

5 3 Hi.in che cua nghien cuu 60

54 K.; h·huon' h'tt·" d�t'· ten ng ! g p a rten e at 61

TAI LI$U THAM KHAO 53 iii ,

CHUONG 4: KET QUA NGHIEN CUU

[a sf> T6ng di�n S6 S6 Chiphik� Chi phi

Tir cac k�t qua phan tich mftu du li�u thu th�p duqc; cac tinh chdt, d�c di�m,

d�c trung cua cac dg an trong mdu du li�u SU d\mg cho nghien cfru nhu sau

30

-� - - � - · -

-CHUONG 4: KET QUA NGHIEN CUU

Normal Q-Q Plot of Standa1·dizecl Residual

Observed Value

lflnh 4.15 Bidu i:16 tdn sci Q-Q phdn du cua hinh thuc CDT "tu nhiin"

Ki�m dinh mo hinh BTC cho hinh thfrc diu thiu "r(>ng rai"

Histogi·mn of Selected Cases

I Dependent Variable: ln(T)

Regression Stanwu·dized Residual

Meal\ a3.19E-16 Std Dev =0.97 1l =lS

Jflnh 4.16 Phan phbi cua phcin du cua hinh thuc EJT "r9ng rai"

40

� -�

CHU'ONG 4: KET QUA NGHIEN CUU

Nonnal Q-Q Plot of Sta11dm·dized Residual

Obse1-ved Value

Hinh 4.21 Biiu d6 tdn s6 Q-Q phdn du cua hinh thuc fJT "chi djnh thdu"

Nhin vao cac bi6u d6 tren ta c6 th� thdy: cac mo hinh BTC d�u th6a man cac gia dinh v€ phuong sai cua phfin du khong d6i, cac scatter plot d€u cho thdy S\I phan tan rdt ng�u nhien cua cac di�m Ben c�nh d6, bi€u d6 tilng s6 va bi6u d6 Q­

Q plot cung cho thdy phfin du <?tia mo hinh tuan theo quy lu�t phan phBi chudn

4 7 Xay dlfng phU'O'ng trinh thoi gian hoan thanh '\I' an bAng mo hinh h6iquy tuy�n tinh bqi

Tir k�t qua tren ta c6 th6 thdy, mo hinh BTC c6 h� s6 xac dinh tuong d6i thftp (R2 da s6 nh6 han 0.5), do d6 kha nang cua mo hinh nay d?i di�n cho tbng th� khong cao Vi v�y tac gia de xu§t m9t phuong trinh UO'C lugng thoi gian hoan thanh d\I an ma r{>ng tir phuang trinh cua Bromilow nhu sau:

T = K*CBi *GFA82 * NFB-, (4) Trong d6:

• T: thai gian hoan thanh d\I an (ngay)

• C: chi phi th\IC t� hoan thanh d\f an (ty VND)

• GF A: ff>ng di�n tich san (m2

• NF: s6 tfing cao

• K: h�ng s6 mieu ta thai gian th\Ic hi�n d\I an v&i chi phi th\fc hi�n d\f

an la I ty VND trong I m2 a 1 tfing

• B 1: hiing s6 mieu ta thoi gian th\IC hi�n d\I an bj anh huang b&i quy

mo dv an dugc do bing chi phi

43

,

CHUONG 4: KET QUA NGHIEN CUU

'

Ba mdu dem vao ki€m djnh bao g6m: mdu CTI la lo�i hinh dµ an chu dfiu tu

"tu nhan"; CT2 la lo�i hinh dµ an "thuang m�i"; CT3 la lo�i hinh dµ an chu dfiu tu

trinh BTC tim duqc:

Bang 4.9: Kit qua ki�m nghiem cac mlu theo.BTC

duqc)/(ti�n d{> quan sat duqc)

Nh�n xet: 't·

K�t qua ki€� djnh cho thfiy phfin tram sai s6 cua k�t qua phuang trinh so v&i s6 li�u quan sat la tuang d6i Ian cao nhfit la 15.09% Tuy nhien phfin tram sai s6

tuang d6i thfip)

khac

57

PHU LUC • •

:ac bai bao da dU'Q'C dang tren T,p chi Xay Dl}'ng va

T,p chi khoa hQc - D,i hQc MO' TP.HCM

· - -� - ' "-· -

-,, Bang 2: Tong hqp cac thOng so thong ke cua hoi quy cho tung lo�i di} an

Model

(Constant)

ln(GFA) (Constant) Giao dvc

ln(GFA) (Constant)

(Constant) th\'.rc

the hi�n mi'.rc dq phu hc;,p cao so voi tong

va ket lu�n mo hlnh hol quy tuyen tfnh xay

di,tng duc;,c phu hc;,p vbi tong the

Ap d1,mg mo hlnh h6i quy b9i tuyen

tinh cho cac di,t an xay d1,1ng a Vi�t Nam

thu dlJQC ket qua nhll sau:

Tat ca:T:::60.4*Nf0 446 *GFAo 136

Lo�I hlnh di,t an giao dvc:

3.4 Kiem tra cd hay khdng SI/ vi ph9m 3.5 Kiem nghi�m mo hlnh di/ bdo v(Ji den cdc gia df nh cua mo hlnh h6i quy mau kiem tra

sc'S khOng doi Va gla djnh phan ph6i chuan sat barf dau cua 3 cOng trlnh dung de kiem

Quan sat cac Hlnh rva Hlnh 2 ta c6 the nlAu dlJQC chqn ngAu nhien (fe dlla vao

' -��:-

,

I

f I

Doan Thi My Hi.tnh Trjnh Thuy Anh Trlldng My Di@m Phan Tot H6ng Xw\n Nguy@n Tht Hoai Minh TrttdngMy Di@m

U Thi Hiing Giang

Nguy@n Van Phuc Trang Tot Tuyln Anh Nguy@n Minh Ha Nguy@n Hilu Tjnh

Lttu Trucing Van Phtm Chi Cang Nguy@n Quil'c Nghl

Lim Thi Anh Quyen Tr4n Tit Van Anh

Nguy@n Xw\n Nghia Trjnh Thuy Anh

Xu hltdng phat triin ciia Giao di.ic Md va

Tu xa tren the' gidi hi�n nay Khao sat nhu du hqc li�u di�n tit va chltdng trlnh dao t�o Tu xa ciia nganh QTKD

Phat triign nganh DNA hqc - H� Dao t�o Tu xa g6p ph!n thl!c hi�n xay dl!ng cQng d6ng ASEAN 2015 Xay dl!ng hi�u qua ciia ho�t dQng di! gio

Giao trlnh dit;n tit: Nhung tit;n ich va mQt so' giai phap phat triin

Di xay dl!Ilg mQt giao an dit;n tit bhg ht;

thffng Moodie

KINH TE - KHOA H()C KY THU! T

Phan tich chu6i gia ttj lua g�o t�i tinh Tra Vinh, D6ng B1ng Song Citu Long :

Cac ye'u t6 tac dQng de'n tinh tr�ng ngheo ciia hQ gia dlnh d Nong Thon ( Nghien cuu trltong h�p tinh Blnh Phltdc)

Mo hlnh danh gia m6i quan he$ giua thoi gian va chi phi ciia cac di! an xay dl!ng t�i Vit;t Nam Cac nhan to' anh h1tdng de'n nhu cfo tin d 1; mg chinh thuc ciia cac dan t(>c thiigu so': Nghien cuu trltong h�p ngltoi KHMER d Tra Vinh va ngltoi Cham d An Giang Thi.tc tr�ng lao d(>ng - vic$c lam cua thanh nien trong qua trlnh chuyin dich cd cffu kinh te' t�i Huyt;n Cao Lanh va TP Cao Lanh tinh D6ng Thap

,:_1 A <rt,

TRAO DOlDIEN DAN

Sit d1;mg cac pMn m�m chuyen di.ing trong nghien cuu djnh tinh

Ban v� vi(:c phat triin kho hqc lit;u di(:n tit

JOURNAL OF SCIENCE

Editor-in-chief: Associate Professor NGUYEN TRUAN, Ph.D

Editorial Office: 97 Vo Van Tan, District 3, HO cm MINH City

TEL: (84.8) 39300077 - FAX: (84.8) 39300085

VOL 3 (18) - 2010

ISSN 1859 3453 E-mail: tapchikhoahoc@ou.edu vn

LE BAO LAM

VU VIET HANG

HUA VAN DUC

DOAN THI MY HANH

TRINH THUY ANH

TRUONG MY DIEM

PHAN THI HONG XUAN

TABLE OF CONTENTS

EDUCATION - SOCIAL STUDIES

Open University in Accordance with Students of Distance Education

World Current Trend in Open and Distance Education

An Investigation into the Need for Electronic Resources and Distance Program of Business Administration Developing Southeast Studies for Distance Education

as a Part of the_ ASEAN Community Buildup 2015

NGUYEN THI HOAI MINH Towards Building up the Effectiveness of Classroom Observation

TRUONG MY DIEM

LE THI HANG GIANG

NGUYEN VAN PHUC

TRANG THI TUYEN ANH

NGUYEN MINH HA

NGUYEN HUU TINH

LUU TRUONG VAN

PHAM CHI CONG

NGUYEN auoc NGHI

LAM THI ANH QUYEN

TRAN TU VAN ANH

NGUYEN XUAN NGHIA

TRINH THUY ANH

Electronic Lesson Plans: the Utility and Some Solutions for Development

Towards Designing an Electronic Les�on Plan with Moodie

ECONOMICS - SCIENCE & TECNOLOGY

Reality of Labour - Jobs for Young People in the Change

of conomic Structure in Cao Lanh District and Cao Lanh City, E>ong Thap Province

VIEWPOINT EXCHANGE - FORUM

Using Specialized Softwares in Qualitative Researches

Discussion on Electronic Materials Resources

) TAP CHI KHOA HOC SO 3 (18) - 2010

-MO HINH DANH GIA -MOI QUAN H�

GIU A THO} GIAN VA CHI PHI CUA cAc DU AN •

XA Y DUNG TAI VIET NAM • • •

000 din niim 2010, va chi phi thf!C hi?n.d11 an dli duvc hi?u chinh vJ cimg m(jt thai tliJm g6c

v la niim 2009 Phdn mdm SPSS la cong q, chinh dung tJJ phan tich dft li?u Ky thugt phan tich rU'(Jc dung la phan tich h6i quy tuyin tinh a0'/1 Kh qua nghien CU'U la m<)t cong q, tham khao cho 1hung nguili trong nganh xay d1p1g tgi giai dogntldu trong qua trinh thf!C hi?n d11an tgi Vi?t Nam

rJ d11 bao thai gian thf!C hi�n d11 an

Abstract

The project duration estimation plays a key role in the ear"/y phase of construction projects

!his paper aims to develop the re gr ession model for predicting Jhe construction duration of :onstruction projects Based on a data set of 57 construction projects implemented from 2000 to W!O, the Browmilow s model is developed using Multiple Linear Regression (MLR) The SPSS iojtware is a main tool to analyze the data set The results of this study are re gr ession functions for wch type of construction projects These findings can be used as a tool to predict the· construction iuration in early phase

1 Gioi thif u

Tinh tr�g vuot chi phi va cham ti�n do

Kciy ra thucrng xuyen a tfit ca cac dµ an, tfit ca

cac linh V\IC VO'i quy mo va dijc di€m khac nhau

Trong b6i canh n8n kinh t8 thi trucrng, sµ qmh

tranh giua cac cong ty xay dµng rftt kh6c liet,

do d6 cac nha thdu khong ngimg phai cai ti8n

bien phap thi cong, each thuc quan ly ds giam

chi phi, giam thcri gian thi cong dµa tren nang

dµ an xay dµng thuong duqc ti8n hanh duoi nhung di�u ki�n rui ro khac nhau f)i�u nay se tac dong d8n vi�c UO'C luqng thoi gian thµc hi�n cong viec ciing nhu chi phi cho cac cong viec d6 trong qua trinh lap ti8n do N8u c6 dUQ'C cac

du Heu luu tru cho thcri gian va chi phi ciing nhu nhan vat lµc cho viec thµc hien cac cong tac se giup ich rfit nhi8u cho nguai lap ti8n do

dµ an

h.rc hi�n c6 ma v!n dam bao chftt luqng Di8u Nghien cuu nay hinh thanh nhim xay nay doi hoi phai CO mot Cong C\l trQ' giup cac dµng mot mo hinh dµ doan dUQ'C thoi gian thi nha thdu CO th€ tinh toan duqc chi phi Va thcri Cong dµa tren chi phi da dUQ'C · UO'C tinh, nhim gian thi cong dang tin cay nhfit Ngoai ra, Cac :-0ua ra mot ti8ri do thi cong hqp ly ph1,1c V\l cho

•Tnrcmg khoaXciy D1p1g va Di?n tnlcmg Dgi h ,;x: Mu TP.HCM

•*Cong ty TNHH Kim C11crng

cong tac dftu thdu ciing ·nhu tinh tr�ng tr� ti�n

do trong cac dµ an xay d1,mg t1;1i Vi�t Nam D6

KINH TE - KHOA HQC KY THU,; T 71

la mo hinh xay d\ffig m6i quan he gifra thcri gian

va chi phi theo m6.i quan he giua thcri gian va

chi phi cua Bromilow (BTC)

T=KC0

Trongd6:

mJt bfutg cfing trucmg cho toi ngay hoan

thanh th\IC tS

C: la J6ng chi phi cu6i cung cua d\f an �iSu

chin4 tm h�ng s6 gia nhan cong va v�t tu

K: la hfutg s6 mieu ta mfrc d9 chun� cua thcri

gian th\IC hien VOO gia 1 dan vj chi phi

B: la hfutg s6 mieu ta S\f anh hucmg cua quy

mo d\f an too thcri gian th\IC hien d\f an dugc

do lucmg boi chi phi

2 LtrC}'C khio cac vin d@ di nghien CU'U

Mfii quan· he giua thcri gian va chi phi

hoan thanh m9t d\f an xay d\ffig da dugc thanh

l�p lAn ddu bm Bromilow (1974) vm viec khao

duqc c�p nh�t va chinh sira bm Bromilow

du Heu thcri gian- chi phi cua 419 d\f an xay

trung binh cua d\I an la mQt ham theo chi phi d\I

Nghien cuu Ireland (1993) ciing d\I bao

m6i quan he thcri gian va chi phi cua cac d\I an

phi duqc quy vs �cri diem xiiy d\ffig thang 6

nam 1979

Nhfrng nghien cuu tren t�p trung (I cac d\f

an xiiy d\ffig dan d\lllg, Kaka va Price ( 1991) da

Heu la cac d\f an ducmg trong khming thoi g1an

h� th\fC te ciing duqc tim thfty MQt nghien ciru

m6i quan h� giua thcri gian va chi phi cua 67 d\f an cong c(>ng, 20 d\T an tu nhiin va 51 d\f an

nghia (level of significance) 0 000 vm phuang trinh theo thu t\f sau (Yeong, 1994)

d\ffig n6i chung va cong b6 phuang trinh cua Bromilow dSu phu hgp voi hai lo�i hinh tren

HQ dS nghi dua them cac biSn vi m6 vs d\f an nhu chi phi xay d\ffig, tdng dien tich san xay d\lllg, sA tAng, va cac nhan tA vi mo anh hucmg dSn nang suftt lao d(>ng, cfulg nhu cac ySu t6 y nghia khac' co anh huong den thai gian hoan thanh d\f an M(>t chu6i nghien ciru sau nay cua Chan (1999) Ongnghien ciru miu du Heu g6m

th\IC hi�n nhu sau:

Love va cac c(>ng S\f (2005) da th\IC hien m(>t phan tich vm m9t dfr lieu nh6m cua 161 d\l an xay d\lllg t�i tirng khoang thcri gian d\f

an, lo�i d\I an va kSt qua da chi ra ring chi phi

la nhan tA khong hieu qua khi UO'C luQ'llg thoi gian th\IC hien d\I an Cac nha nghien ciru da

dS xudt them nhan t6 tdrig dien tich san (GFA)

va s6 t!ng (Floor) vao mo hinh de d\I bao thcri gian va chi phi nhfun lam cho phuang trinh cl.ia� Bromilow them d\f bao chinh xac

' - ;_ _ -

-· -72 T�P CHf KHOA HQC SO 3 (18) - 2010

Ogusemi va Jagboro (2005) phat tri�n

m6i quan he giua thoi gian va chi phi theo

Bromilow nay o Nigeria v6i ho mdu du lieu

g6m thai gian va chi phi thuc ts cua 87 du an

da hoan thanh trong khoang thoi gian tu nam

1991 dSn: nam 2000 Mdu du Heu da duc;rc h6i

quy tuySn tinh, sau d6 h6i quy theo tung mdu

du Heu nho hon va duc;rc phan chia theo diSm

gay (la diSm ma duong h6i quy gay khuc)

Theo diSu kien dac diSm van h6a kinh ts· xa

hoi o Nigerian, mo hinh thoi gian chj phi cua

Bromilow duc;rc thanh lap: T=63C0 ·262 v6i kha

nang du bao ySu (R=0.453; R2=0.205) Do

d6 Ogusemi va Jagboro da cai tiSn mo hinh

Bromilow · bing viec SU d1,mg cac nh6m du

lieu mau duc;rc phan theo cac dism gay khuc,

di�u nay lam cho kha nang du doan cua mo

hinh tang len dang kS (R=0.875, R2=0.765),

va phuang trinh duc;rc tini th§.y:

T=l18,563-0.401C (C�08) hoac T=603,427+0.610C

(C>408) Mo hinh dli cho th§.y su hiiu ich trong

viec du doan thm gian hoan thanh du an

Bromilow (1969; 1980; 1988); Sidwell

(1984) va Walker (1995) da tim ra "chi phi"

chinh la chia khoa dS xac dinh thoi gian thuc

hien du an (1 Australia Love cung cac cong S\l

(2001) sau khi da kiSm tra va sua dBi hii mo

hinh BTC vai bo du Heu mai, so sanh vai nhiing

nghien cuu truac day o Australia dli nhan ra

r�g cht�u dai cua mot don vi thoi gian xay

dung thay d6i theo tung giai do�n thm gian Va

hQ Cung k�t luan S\l Ca(ti�n trong xay dung da

phat tri�n mi;mh me hon 3 thap ky qua so vai

thoi ky nghien cuu cua Bromilow (1969)

Chan (1999) nghien cuu a Hong Kong da

kham pha ra ring m6i quan he giua thoi gian va

chi phi la mot Cong C\l tien lc;ri cho nhung nguoi

irng d\lng mo hinh nay trong xay dung a cac du

an cong cong hay nhung du an tu nhan Clian

(2001) thuc hien mot nghien cuu tuang tu cho

cac du an cong c9ng tu nhung nam cu6i thap niem 80 cho dSn dAu nhung nam tiiap nien 90 a

Malaysia va gi6i thieu mo hinh irng d\lng BTC MQt nghien cuu khac, Endut cung cac c{mg su (2006) dli cho th§.y khong c6 can.cir dS d� nghi tfit ca cac tham s6 dv an d�u tuan theo

mo hinh BTC Mdu du Heu cua Endut (2006) 1§.y tu cac du an dli duc;rc thuc hien tu nam 1995 dSn nam 2005

Chen va Huang (2006) dua ra quan di�m

la chi nhung dv an xiiy dung tu nhan la tuan theo mo hinh nguyen thuy cua BTC Trang nghien cuu nay, thoi gian thuc hien cac du an cong cong thi ciing gi6ng nhu phuong trinh ctia cac du an tu nhan tuy nhien chi phi xay dung duc;rc thay b!ng nhan t6 dien tich san xay dung

Tu d6 that d8 dang ta thdy r!ng, cac tham s6 trong mo hinh B TC khong d6ng nhfit trong tung thai do�n, tung thi truang, va dac diSm ' dac trung tung du an Tuy nhien viec ung d\lng

mo hinh MC trong viec UO'C luc;rng va chdm di�m chu�n cho thoi gian xay dung la rdt m�nh

va n6 se giup ich ��o cac nha quan ly xay dung

Va cac chuyen gia trong linh V\lC nay

CJ Viet nam, chua c6 nghien cuu nao khao sat m6i quan he giiia thoi gian va chi phi cua cac

du an xay dung theo phuang trinh Browmilow

3 Phat tri�n mo hinh 3.1 L\fa ch9n miu dU'a vao phll'ong trinh h6i quy

Su dl)ng bi Su d6 Boxplot danh gia theo tung bi�n ds lo�i ho cac mau co gia tri phan tan qua xa so v6i toan bQ mdu nghien cuu T6ng du

an dua vao nghien ciru la 67 du an, can cir vao bi�u d6 Boxplot cua cac bi�n ta thdy phai lo�i

bo cac mfiu c6 cac bi�n c6 gia tri qua Ian so vai trung binh mfiu khao sat Do d6 t6ng s6 mfiu dem vao phan tich chi con 59 mftu tuy nhien 6

mftu bi lo� bo van giu l�i d� kiJm chung l�i kJt qua mo hinh h6i quy nay