MULTIDIMENSIONAL RELIABILITY OF INSTRUMENT STUDENTS SATISFACTION USING CONFIRMATORY FACTOR ANALYSIS ABSTRACT

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1 Avalable onlne at IJER Webste: Indonesan Journal of Educatonal Revew, Vol. 1 (), 014, MULTIDIMENSIONAL RELIABILITY OF INSTRUMENT STUDENTS SATISFACTION USING CONFIRMATORY FACTOR ANALYSIS Gaguk Margono Graduate School, Unverstas Neger Jakarta g_margono@yahoo.com ABSTRACT The purpose of ths paper s to compare undmensonal relablty and multdmensonal relablty of nstrument students satsfacton as an nternal costumer. Multdmensonal relablty measurement s rarely used n the feld of research. Multdmensonal relablty s estmated by usng Confrmatory Factor Analyss (CFA) on the Structural Equaton Model (SEM). Measurements and calculatons are descrbed n ths artcle usng nstrument students satsfacton as an nternal costumer. Survey method used n ths study and samplng used smple random samplng. Ths nstrument has been tred out to 173 students. The result s concluded that the measurngnstrument of students satsfacton as an nternal costumer by usng multdmensonal relablty coeffcent has hgher accuracy when compared wth a undmensonal relablty coeffcent. Expected n advanced research used another formula multdmensonal relablty, ncludng when usng SEM. Keywords: multdmensonal relablty, nstrumentof students satsfacton as an nternal costumer, confrmatory factor analyss. Accordng to the Latan (01) Structural Equaton Modelng (SEM) s a second-generaton multvarate analyss technque that combnes factor analyss and path analyss that allows researchers to smultaneously test and estmate the relatonshp between exogenous and endogenous multple varables wth many ndcators. Joreskog research results n the 1970s brought on the statstcal theory of lnear structural analyss that s better known as structural equaton modelng or SEM. Important source s used n analyzng the covarance structure so that ths approach s sometmes called the covarant structure model (CSM). The model ncludes varables drawn mmeasurable called the latent constructs were constructed by a set of measurable varables, called the construct measured. Measurement error of measurement reflectng the relablty scores are seen as a unque construct and become an mportant part of SEM analyss, measurement errors were ncluded n the SEM analyss s then be compared wth the advantages of SEM other analytcal technques (Capraro et al., 001). SEM can estmate the error varance n the actual measurement outcome scores estmatng the relablty. Accordng to Geffen and colleagues (001), SEM as multvarate statstcal technque that combnes multple regressons to dentfy relatonshps between constructs and factor analyzes that dentfy the concept was measured by several ndcators manfest that both are used smultaneously.the frst approach s the correlaton correcton attenuaton caused by measurement error and the second approach s a structural equaton model n the context of confrmatory factor analyss. Lee and Song (001) sad that SEM s one approach to confrm the measurement model. In the SEM measurement model lnkng the latent constructs

2 Indonesan Journal of Educatonal Revew, Vol. 1 (), 014 wth emprcal construct. Emprcal constructs expressed by a combnaton of latent constructs. In addton be able to and capable of handlng generalzablty theory and tem response theory, SEM s able to compare the measurement model and the accuracy of the model facltates nvestgaton. SEM has two basc components. Frst, the measurement model s defned as the relatonshp between latent varables and a group of explanatory varables that can be measured drectly. Second, the structural model s defned as the relatonshp between latent varables that cannot be measured drectly. These varables also dstngushed as ndependent varables and the dependent varable. Geffen and colleagues (001) sad that the measurement model s sub-models n the SEM wth latent constructs that dentfy the ndcators that can be used to determne relablty each construct were ncluded n the model. SEM can also dentfy relablty constructs are vsble through the resultng value of the gran loadng. Based on the perspectve SEM construct relablty can be calculated through the followng equaton: CR Descrpton: CR =Construct relablty =Factor loadngof standardzedndcatorsto- =Standard error of measurement McDonald (1981) formulate are lablty coeffcent whch later was named a McDonald composte score relablty coeffcents are also called omega ( ). Relablty coeffcent s based on confrmatory factor analyss that s part of the menu SEM modelng. Ths composte score relablty McDonald explans the large proporton of ndcators n measurng the construct explaned. The formula to obtan the constructrelablty coeffcents are as follows: Descrpton: = Factor loadng of standardzed ndcators to- When compared between the relablty of the constructs wth a composte score relablty McDonald wll gve the same result as 1.

3 Indonesan Journal of Educatonal Revew, Vol. 1 (), 014 The followng s a relablty coeffcent multdmensonal construct relablty coeffcents developed by Hancock and Mueller (000) that shows how well the ndcator could reflect the construct to be measured. Ths coeffcent s a modfcaton of the McDonald construct relablty coeffcent was not able to accommodate dfferent weghts nterdmensons. Modfed construct called relablty coeffcents weghted as follows: w p 1 1 p l (1 ) 1 l l l (1 ) Descrpton: l = Coeffcent of the -th standardzed dmensons The relablty coeffcent can be nterpreted as the square of the correlaton between the dmensons of the optmal lnear compostes, so some experts call t the maxmum relablty. In measurng student satsfacton used a measure of subjectve or soft measures as qualty ndcators or qualty. Ths sze s called soft, because these measures focus on the perceptons and atttudes rather than concrete thngs called objectve crtera. Therefore, focusng on the perceptons and atttudes of the gauges used to be a student satsfacton questonnare whch can be measured by the qualty of servce or the qualty of hgher educaton nsttutons. The qualty s a term that s constantly movng dynamc; movng forward f the qualty s sad to be better, otherwse f t moves backward to say qualty deterorated. Qualty means can mean superorty or excellence that exceeds the general standard. Somethng sad to be qualfed f there s a match between the requrements that are owned by the desred object or servce wth the ntent of the wsh. Accordng to Idrus et al. (000) "... the purpose of ftness as perceved by the customer." For example, the qualty of the learnng process matches what s expected by the student; growng far beyond what one would expect more qualty, f the opposte occurs, the more not qualfed. The frst step s to dentfy the servce qualty measure servce qualty characterstcs. Lst these characterstcs can be generalzed n many dfferent ways usng a varety of resources. One way s to look for lterature lke journals that may contan the dmensons of servce qualty. Researchers such as Parasuraman, Zethaml, and Berry (1985) have concluded that the qualty of servces can be descrbed on the bass of 10 dmensons. Tryng to measure ten dmensons, t turns out the customer can only dstngush 5 servce qualty (servqual) dmensons, Parasuraman (1988) suggest that the dmensons of the orgnal 10 overlappng one another. Fve dmensons of servce qualty s somethng that materalzed (tangble), relablty, responsveness, assurance, and empathy. More on ths dmenson can be read from the publcaton of the qualty of servce by Zethaml, Parasuraman and Berry (1990). The frst dmenson of qualty of servce accordng to the concept of tangble servqual ths s because a servce cannot be kssed and ntangble, tangble t becomes

4 Indonesan Journal of Educatonal Revew, Vol. 1 (), 014 mportant as the sze of the servce. Tangble s the ablty to provde the campus physcal facltes and equpment adequate lecture concernng the appearance of employee/faculty and offcals as well as publc facltes. For example: the avalablty of space concernng the completeness and avalablty of equpment, comfort and sophstcaton of the campus, computer and nternet facltes, lbrary, lecture halls, semnar rooms, faculty rooms, meda lectures, laboratores, unts of producton, canteen, career gudance centers, health servces, places of worshp, rest areas and parkng lots, as well as means of transport. Students wll use the sense of sght to assess the qualty of care of all the facltes and exstng facltes. Second, the relablty dmenson s a dmenson that measures the relablty of hgher educaton n provdng servces to students. There are two aspects of ths dmenson are: (1) the ablty of unverstes to provde servces as promsed wth proper and relable, and () the extent to whch colleges provde a servce that s not accurate or error. In other words, relablty s the ablty of ts offcers, employees/faculty n provdng servces n accordance wth the promsed (on tme), wth mmedate, relevant and accurate so as to satsfy the students. Example: development admnstraton, currculum and offers courses as demanded skll, professon and the world of work, the lectures take place smoothly on schedule, assessment study objectve, far and tmely. Thrd, responsveness s a dynamc dmenson of servce qualty, a wllngness to help students and provde a servce or servces quckly. Expectatons of students to the speed of servce wll almost certanly change the upward trend over tme. Responsveness s the wllngness of offcals, faculty/staff to assst and provde servces accordng to the needs of the students. Example: offcals easly found for the requested relef, the lecturer easly found for the purposes of consultaton, ongong learnng process nteractve and vared, and allows the students to develop the capacty and creatvty, managers provde adequate facltes accordng to the needs of students and the world of work. The fourth dmenson of servce qualty dmensons that determne customer satsfacton s the assurance that the dmensons of qualty assurance related to the company's ablty and behavor of front- lne staff n nstllng a sense of trust and confdence to the students. Assurance ncludes competence, knowledge, sklls, polteness, respect for every person and trust propertes owned by the staff. Example: the lecturers delvered lectures n areas of expertse/experence, professors are always tryng to add nsght by readng, attendng semnars, tranng, further study, do research, have a good atttude and behavor, as well as all levels of the organzaton reflects the professonalsm and n accordance wth the set n the standard. Ffth, empathy s the ablty of ts offcers, employees/faculty so as to gve wholehearted servce, among others, ease of communcaton, personal attenton, awareness and understandng n student s specfc needs of ndvdual students. Example: lecturers get to know the name of the students, faculty academc advsor truly act as a counselor and as a supervsor s not just a language edtor, and offcals can easly be reached ether n the offce, va phone, emal and so on. Ths empathy relates to the development of human needs theory of Maslow. At the hgher level, human needs are no longer the prmary thngs such as physcal, and socal securty are met, then two more needs to be pursued by humans, namely the need for ego and

5 Indonesan Journal of Educatonal Revew, Vol. 1 (), 014 self-actualzaton. Lattertwo requrements whch are assocated wth the dmensons of empathy. Furthermore, Kotler (1994) stated that customer satsfacton s "... the level of a person 's felt state resultng from comparng a product 's perceved performance (outcomes) n relatons to the person 's expectaton." Student satsfacton s a condton that one feels that the result of comparson between the results expected of a product / servce wth the realty that s accepted. Thus, the level of student satsfacton depends on the ft between the achevement levels of qualty of servce or servce purchased wth student expectatons. In educaton, psychology, economcs, busness, and management, good judgment requres relable measurement or trustworthy. Smlarly, n the feld of educaton and psychology. Accordng to the Naga (199) for educatonal and psychologcal measurement ncludes several thngs. Frst, measure the latent trat that s nvsble to the respondent. Secondly, to measure the characterstcs of the latent form of the questonnare respondents were gven stmulus or approprate measurng nstruments. Thrd, the stmulus responded by respondents wth expectatons correctly reflects the response latent trat to measure. Fourth, the response can be scored and nterpreted adequately. Then, wthout queston the extent to whch scores obtaned can accurately reflect the latent trat to be measured? Is the nstrument was used as a stmulus to reveal the latent trats properly unseen? The second queston regardng the valdty. Beng assocated wth relablty, whether the responses gven by the partcpants are to be beleved to be used as materal for scorng psychologcal attrbutes that? Accordng to Wersma (1986), relablty s the consstency of an nstrument to measure somethng to be measured. Relablty ndcates the extent to whch the results of measurements wth the devce can be trusted. Therefore, relablty s an ndex that ndcates the extent to whch a measure can be relable or unrelable. When an nstrument s used repeatedly to measure the same symptoms and the results obtaned are relatvely stable or consstent, then the relable nstrument. In other words, the measurement results are expected to be the same f repeated measurements. Broadly speakng there are three major categores of measurement relablty: (1) the type of stablty (e.g., retest, parallel forms, and alternate forms), () the type of homogenety or nternal consstency (eg splt half, Kuder-Rchardson, Cronbach's alpha, theta and omega), and (3) type equvalent (e.g., parallel to the gran of alternate forms and nter-rater relablty. The nstrument was gven to one group of subjects and n a certan way calculated estmates of relablty. Ths one-tme measurement approach generates nformaton about the nternal consstency of the nstrument. Internal consstency s a measure such statements or to reflect the same aspect of a gran homogenety statement. The hgher the relablty coeffcent, the closer the value of observaton scores wth actual scores, so a score of observaton can be used as a substtute for the real component of the score. Sze of hgh or low relablty coeffcent s not only determned by the value of the coeffcent. The nterpretaton of hgh and low coeffcent value obtaned throughcomputaton s also determned by the standard dscplnes nvolved n the measurement. The hgher the coeffcent of relablty of an nstrument, the possblty of errors that occur wll be smaller f people make decsons based on the score obtaned n the nstrument.

6 Indonesan Journal of Educatonal Revew, Vol. 1 (), 014 In general, the measurement of affectve characterstcs provde relablty coeffcent lower than the measurement of cogntve, because the cogntve characterstcs tend to be more stable than affectve characterstcs. Accordng to Gable (1986) cogntve relablty coeffcent of the nstrument usually about 0.90 or more, whereas affectve nstrument relablty coeffcent of less than Relablty coeffcent of 0.70 or more at the level generally accepted as a good relablty (Ltwn, 1995). Whereasaccordng to the Naga (199) should be adequate relablty coeffcent s above In each study usng psychologcal measurement always apply the test valdty and relablty. But along the way n the feld of psychometrcs, among the experts there were no agreement about the relablty coeffcent or formula where for relablty among researchers. Frst, many researchers are consdered qute competent stll much less precse n reportng the relablty of the results of ther measurements (Thompson, 1994). Second, the problem that arses s the use of relablty coeffcents by researchers consder a monotoncally wthout the assumptons underlyng coeffcent. The researchers unknowngly usng alpha coeffcents were also wthout realzng that for ths coeffcent requres assumptons that are dffcult to fulfll. If the assumptons are not met then the resultng alpha coeffcent s the estmated value at the lowest lmt. Many researchers only focused on the use of coeffcent alpha to estmate relablty. Cronbach s alpha coeffcent ppopulartyes born because of factors: 1) computatonal technque s relatvely easy, as t only requres nformaton such as the total score varance, and ) the samplng dstrbuton s already known that the determnaton of confdence ntervals on the populaton s very possble (Feld et al., 1987). Thrd, the problems assocated wth the assumpton that the condton for estmatng the relablty. In the emprcal realm other than the requrement of the nature of parallel, tau-equvalent terms s a tough challenge for researchers n developng measurement nstruments. Ths s supported by Kamata et al (003) who found that the assumpton of equalty, the power of dscrmnaton between test components, and undmensonalty measurement s relatvely dffcult to acheve. If the assumpton of tau-equvalenteessentally cannot be met then the coeffcent alpha relablty values whch produce very small, so t s below the estmatedcoeffcents. Fourth, dscourse undmensononalty measurement s the measurement problem. Undmensonalty s an mportant aspect n estmatng relablty. Psychologcal measurement results are undmenson very dffcult to acheve, especally n the context of the personalty doman that contans most of the area varances broad trats. Socan (000) wrtes that the factor analyss of several studes conducted many cases multdmensonal compared wth undmensonal. Assumng the problem s not a major ssue n developng a model of nternal consstency, but the problem s the subject of study of many researchers n the assessment of relablty. As research Vehkahlat (000) who concluded that the assumptons are not realstc enough to score a purely classcal theory s the assumpton that pure scores undmensonal practcally dffcult to prove. So study multdmensonal surface measurements because many cases also found that the correlaton between the dmensons of tems n the sometmes hgher than the correlaton between the tems n the test.

7 Indonesan Journal of Educatonal Revew, Vol. 1 (), 014 On the development of measurement nstruments n the feld of educaton assumes the use of many measurements that are conceptually formulated undmenson that there s only one knd of capablty factors, personalty, trats, and atttudes as measured by the measurng nstrument. However, many studes have shown that the assumpton undmenson dffcult for the dscovery of several new factors nvolved are measured n one nstrument. In other words, the nstrument that s often used psychologcal research tends to be multdmensonal. Some mportant reasons multdmensonal measurement relablty as suggested by Wdharso (009) wth the followng descrpton: Frst, the general characterstcs of the psychologcal construct are multdmensonal.second, any nvolvement n the preparaton of the aspects of psychologcal nstruments s usually preceded by a decrease n gran of some theoretcal aspects and the tendency s multdmensonal. Thrd, the number of tems n the nstrument. The numbers of tems that can add too much addtonal potental error varance n tem gvng rse to new dmensons of the orgnal defned dmensons. Total gran and also forms the scale affect respondents' atttudes toward the tem then affect ther response to the nstrument. Fourth, tem wrtng technques. Spector and colleagues (1997) found that the technque of wrtng tem that have reversed drecton between postve (favorable) and negatve (unfavorable) to form a new dmenson when measurng the data capture many psychologcal scales usng dfferent wrtng technques gran drecton. Ffth, dfferent measurement unts.measurement of psychologcal feldstends to have dfferent measurng unts between tems one wth the other tem have dfferent cavaltes measure as an ndcator construct. Ths condton wll cause the measurement results tend to be multdmensonal. In Wdharso research and Mardap (010) multdmensonal model for measurng the relablty coeffcent has hgh accuracy when compared wth the relablty undmenson. Therefore, n ths study, researchers focused only on multdmesonal relablty and undmensonal relablty.ths study ams to test the accuracy or relablty coeffcent multdmensonal accuracy when compared wth a relablty coeffcent undmensonon. Based on the above t s rased a range of questons such as: What s the nternal consstency relablty of a multdmensonal nstrument measurng student satsfacton as an nternal customer? How does a comparson between the multdmesonalrelablty and undmensonal relablty? Whch s more accurate as a measure of relablty? METHOD The method used n ths study was a survey method. The survey used n the data collecton and made no treatment (treatment) or the condtonng of the varables studed, but only reveals the fact that there are symptoms based on the student or other respondents.in ths tral obtaned a sample of 173 respondents students from ManadoState Unversty (Unma) n October 013. Scale research nstrument made of two columns wth detals, for the frst column s a realty or the fact that there was and s perceved by students to satsfy servce qualty wth fve alternatve answers rangng from very dssatsfed (vd)

8 Indonesan Journal of Educatonal Revew, Vol. 1 (), 014 value of 1, s not satsfed nd) value of, neutral (ne) value of 3, satsfed (sa) value of 4, and very satsfed (vs) value of 5. The scale was for the performance nstrument.for the second column, the expectatons of students to nsttutons wth an alternatve fve-pont scale based on the level of student nterest wth answers rangng from very unmportant (vu) value of 1, somewhat mportant (s) values, neutral (ne) 3 value, mportance (m) value of 4, and very mportant (v) value of 5. The scale was for expectaton nstrument. RESULTS AND DISCUSION 1. Performance Instrument The performance of the nstrument conssts of a 30 tems questonnare statement of student satsfacton as an nternal customer. Thrteth nstrument of ths tem s the result of research that has been valdated by researchers usng factor analyss. The nstrument conssts of 30 tems can be broken down as follows: 6 statements for tangble dmenson, 7 statementsfor relablty dmenson, 5 statementsfor responsveness dmenson, 7 statements for assurance dmenson, and 5 statementsfor empathy dmenson. Frst to undmenson Cronbach alpha relablty obtaned drectly usng SPSS for Secondly, for whch the relablty of composte relablty multdmensonal omega McDonald, usng the program LISREL 8.8 and Excel programs obtaned: and , so Thrd, for the relablty of the multdmensonal construct relablty obtaned the same results as follows: CR (17.330) (17.330) (19.550) and (17.330) (17.330) (19.54) ,so Fourth, for the relablty of the multdmensonal maxmum relablty, by p l usng by usng LISREL 8.8 and Excel programs obtaned: 1.744, 1 (1 l ) so t can be calculated as follows: w Expectaton Instrument Same wth the performance nstrument, the expectaton nstrument conssts of 30 tems, hopes the statement level of student satsfacton questonnare as an nternal customer. Frst, for relablty alpha Cronbah undmenson obtaned drectly usng SPSS for

9 Indonesan Journal of Educatonal Revew, Vol. 1 (), 014 Secondly, for whch the relablty of composte relablty multdmensonal omega McDonald, usng the LISREL 8.8 program usng the Excel program and obtaned: 1 (0.80) (15.700) 0.80 and , so obtaned Thrd, for the relablty of the multdmensonal construct relablty obtaned the same results as follows: CR (0.80) (0.80) (0.80) (15.450) and , so Fourth, for maxmum relablty, usng LISREL 8.8 program usng the Excel p l program and obtaned: 3.60, and so can be calculated as follows: 1 (1 l ) 3.60 w From the results above descrpton can be summarzed n the form of table as follows: Table 1. Summary of Research Fndngs Relablty CR w Performance Expectaton The calculatons for the above two nstruments multdmensonal relablty coeffcent obtaned relatvely hgher or more precse than the relablty coeffcent undmensonal. It s no agreement among experts psychometrcs. But among researchers n Indonesa should be after knowng the most approprate tool should start usng the tool correctly and adequately. Indeed, most researchers among the faculty and students of both S and S3 do not know the formula for calculatng the relablty coeffcent construct, omega or the maxmum relablty. So ths tme t's tme to ntroduce and use the formula. Wth grounds already know the formula and most psychologcal constructs, personalty, educaton, and socal s multdmensonal, so that all students and faculty researchers developng and growng to dg deeper about the relablty coeffcent others. Measurement of educaton s somethng that s qute complcated. Varous wrtngs n journals rangng from educatonal measurement at the measurement method are expected to provde results that are vald, relable, and accurate. Of busness experts s not easy because the longer the experts brng educatonal measurement that far nto the area of mathematcs. Wthout a wellmastered hgh

10 Indonesan Journal of Educatonal Revew, Vol. 1 (), 014 mathematcs and complcated, we cannot understand the varous educaton journals measurements. So far, we are so far behnd n the feld of educatonal measurement. Very few scence educaton experts who are able to understand the content of educatonal measurement journal studded hgh level mathematcs. Therefore, t needs to be ncreased scence educaton experts n the feld of educatonal measurement. Busnesses can start by changng our percepton has been that long ago, the educators among us have the noton that scence educaton and psychology do not requre math. Now, dealng wth educatonal measurement among educators we need to change ther percepton of mathematcs. Educators need to be aware that there s a part of scence educaton whch hardly uses mathematcs, but there s also a part of scence educaton s n need of mathematcs, such as the example above multvarate statstcs requres hgh mathematcal sklls. CONCLUSIONS Based on the test results of ths study concluded multdmensonal relablty coeffcent s more precse or accurate when compared wth a relablty coeffcent undmensonal. Suggestons can be submtted are as follows: frst, estmate the nstrument needs to be tested further by usng another formula that s not based SEM. Second, because ths study used a fve-pont scale when t s necessary to contnue to use a varety of dfferent scales, such as the semantc dfferental scale, dchotomous scale, Thurstone scale, and so on. Thrd, these nstruments need to be tested usng a larger sample populaton and the wder settng and nvolves several provnces at the same tme, also the school. REFERENCES Capraro, M. M., R. M. Capraro, dan R. K. Herson. (001). Measurement Error of Score on the Mathematcs Anxety Ratng Scale across Sudes. Educatonal and Psychologcal Measurement, 61, Feld, I. S., D. J. Woodruff, dan F. A. Salh. (1987). Statstcal Inference for Coeffcent Alpha. Appled Psychologcal Measurement, II,: Gable, R. K. (1986.) Instrument Development n the Affectve Doman. Amsterdam: Kluwer Njhoff Publshng. Geffen, D., D. W. Straub, dan M. D. Boudreau. (001). Structural Equaton Modelng and Regresson: Gudelnes for Research Practce. Communcatons of AIS. Volume 4, Artcle 7. Hancock, G. R., dan R. O. Mueller. (000). Rethnkng Construct Relablty wthn Latent Varable Systems. Stuctural Equaton Modelng: Present and Future,

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12 Indonesan Journal of Educatonal Revew, Vol. 1 (), 014 Vehkalaht, K. (000). Relablty of Measurement Scales Tarkkonnen s General Method Supersedes Cronbach s Alpha. Academc Dssertaton, Unversty of Helsnk, Fnland. Wdharso, W., dan Djemar Mardap. (010). Komparas Ketepatan Estmas Koefsen Relabltas Teor Skor Murn Klask. Jurnal Peneltan dan Evaluas Penddkan, 14 (1),: Wdharso, Wahyu. (009). Koefsen Relabltas pada Pengukuran Keprbadan yang Bersfat Multdmens. Pskobuana, 1 (1),: Wersma, W. (1986). Research Methods n Educaton: An Introducton. Boston: Allyn and Bacon, Inc.,. Zenthaml, V. A., A. Parasuraman, dan L. L. Berry. (1990). Delverng Qualty Servce: Balancng Customer Perceptons and Expectatons.London: The Free Press.