Rasch Model Analysis On Teachers Epistemological Beliefs

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1 Rasch Model Analysis On Teachers Epistemological Beliefs Amar Ma ruf & Mohamed Najib Abdul Ghafar & Samah Ali Mohsen Mofreh Abstract Epistemological Beliefs are fundamental assumptions about the nature of knowledge and learning. This study aims to develop a questioner measuring Teachers Epistemological Belief. The developed questionnaire was distributed among 100 teachers at Makassar. Rasch Model analysis was used to investigate the validity and reliability of the questionnaire using item polarity, dimensionality, and item fit analyses. The reliability of the questionnaire was tested by conducting person and item separation analysis, person and item reliability estimates. The findings of the Rasch Model analysis showed that questionnaire s items were valid and reliable. Keywords: Epistemological Belief, Knowledge, Rasch model analysis, validity and reliability Introduction Epistemology is a part of philosophy area concerned with the nature and justification of human knowledge (Hofer and Pintrich, 1997). Theories or models of epistemology refers to the nature of knowledge andthe nature of knowing and, thus, provide a standard for our understanding of learning. (Maynard, 1994; Hamlyn, 1995; Hofer and Pintrich, 1997).The nature of knowledge is individuals believe of knowledge and how it is they know, in other words the nature of knowing is defined as the basis of knowledge and the explanation for knowing. Epistemology is concerned with providing a philosophical grounding for deciding what kinds of knowledge are possible and how we can ensure that they are both adequate and legitimate. (Crotty, 1998). In relation with the above discussion, the writer developed an instrument to measure the teachers epistemological belief called Teacher Epistemological Belief (TEB) questionnaire. In order to develop the validity and the reliability of the instrument, the writerreviewed the literature to define concept, construct and operational definition. (MohdNajibGhafar, 2011; Fraenkel, Wallen, and Hyun, 2012; Johnson & Christensen, 2012).The objective of the study was to investigate the validity and reliability of the developed TEB questionnaire using Rasch model analysis. Epistemological Belief Epistemological Belief as a fundamental of knowledge and learning was studied by Perry (1970) who tried to understand how students interpreted educational experiences. Epistemological belief is defined as belief about the nature and acquisition of knowledge (Bruning, Schraw, Norby, and Ronning, 2004; Schommer, 1990; Schommer, 1994). By the year 1994,Schommerdeveloped the notion of epistemological belief into five dimensions namely, (1) Stability/ certainty of knowledge, (whether knowledge is an absolute perspective or relative perspective; (2) Structure of knowledge, (a belief that knowledge is simple complex); (3)Source of knowledge, (whether knowledge is acquired from experts or from social constructions); (4) Control of knowledge, (The belief that relates to the ability to learn, fixed at birth or the ability to learn changes throughout an individual s life); and (5) Speed of knowledge, (The belief that knowledge will only be acquired by the predetermined of time orthe belief that most things can be learned by most people if enough time is dedicated./ perceived as a gradual process). In addition to Schommer s epistemological belief system, MohdNajibGhafar (2009) added four constructs of epistemological belief namely, (1) Implementation of knowledge, (whether the implementation of knowledge performed by the administrators or judge perception or panel);(2) Calculation/ estimate of knowledge, (whether the estimation of knowledge is mean score, quantitybased, numbers, scoring and intensity or personal descriptive, quality-based, value, situation); (3) > RJSSM: Volume: 05, Number: 09, January 2016 Page 106

2 Focus of knowledge, (whether the focus of knowledge is based on society happiness, or individual happiness); and (4) Variable of knowledge. (Whether variable of knowledge can be manipulated or vice versa). Types of Epistemological Belief The approach to evaluation influenced by philosophy of human s perspective in epistemology point of view. This epistemology was categorized into objectivist and subjectivist. (House in Mohamed Najib, 2009).The objectivist epistemology is correlated with the utilitarian ethic (House, 1980; Muhammad Najib, 2009) or in other words it is used to obtain knowledge capable of external verification(inter subjective agreement) through publicly inspectable methods and data. Meanwhile, the subjectivist epistemology is related with the intuitionist/pluralist ethic. It is to acquire new knowledge based on existing personal knowledge and experiences that are (explicit) or are not (tacit) available for public inspection. Rasch Model Rasch model is a psychometric model for examining categorical data, such as answers to questions on a reading assessment or questionnaire responses, as a function of the trade-off between (a) the respondent's abilities, attitudes or personality traits and (b) the item difficulty (Rasch, 1960). The mathematical theory underlying Rasch models is a special case of item response theory and, more generally, a special case of a generalized linear model. Thus, Rasch model is used to analyze the data from instruments to measure the variables that cannot be measured directly, such as the characteristics of ability, attitude and personality. In the Rasch Model, the probability of a specified response (e.g. right/wrong answer) is modeled as a function of person and item parameters (Bond & Fox, 2007). Rasch model analysis is a powerful tool for evaluating construct validity.there are some important aspects of Rasch model measurement should be considered to understand the interpretations of its results analysis. According to Rasch Measurement Model, the validity ofa questionnaire can be referred to the analysis of the output. The main output is the polarity item as a correlation coefficient of measurement point, whichis known as point-measure correlation coefficient (PTMEA Corr).Item polarity is also the early detection of construct validity (Bond & Fox, 2007). Dimensionality is one of the aspect need to be considered in Rasch model analysis. It is important to determine the instrument was measured in one direction and one dimension (Linacre, Bond & Fox, in Samah, 2014). This is to ensure content validity and construct validity of the instrument (Wu & Adams, in Samah, 2014). Rating scale analysis is used to determine the probability of participants responses equally spread between the scales. Not all scales can be used for Rasch model. If the structure calibration is less than 1.40 and more than 5 this scale should be collapsed (Linacre, 2003; Bond & Fox, 2007). Item separation is used to verify the item hierarchy. Low item separation (< 3 = high, medium, low item difficulties, item reliability < 0.9) implies that the person sample is not large enough to confirm the item difficulty hierarchy (equals construct validity) of the instrument. A higher value of separation means greater spared of items and persons along a continuum. Lower values of separation indicate redundancy in items and less variability of persons on the trait. Item reliability means that the items will behave with the same way even when given to the different sample. Person reliability refers to the consistency of person ordering that could be accepted if this sample of persons were given a parallel set of items measuring the same construct (Wright & Masters in Samah, 2014). The accepting criteria in Rasch model is exceeding 0.50 (Bond & Fox, 2007). Infit refers to the scale of fit of an item or a person. Infit means square is transformation of the residuals, the difference between the predicated and observed for easy interoperation. It is expected > RJSSM: Volume: 05, Number: 09, January 2016 Page 107

3 value is 1. As a rule of thumb, values between 0.70 and 1.30 are generally regards as acceptable. Values greater than 1.30 are termed misfiting and those less than 0.70 as overfiting (Bond & Fox, 2007). Research Method A Questionnaire has been developed to measure the epistemological beliefs of teachers in Makassar. The questionnaire includes 36 items which was divided into 10 construct. This study was conducted at Makassar South Sulawesi Indonesia. The participants were teachers of Senior High School in Makassar. The numbers of participants were 100 teachers. The Instruments were distributed to all participants directly. After all participants submitted their instrument, the researcher began to analyze the result.rasch Model analysis was used to investigate the validity and reliability of the developed questionnaire. The Rasch Model analysis was used to test the construct validity using item polarity, dimensionality, and item fit analyses. Findings The Instrument of Teachers Epistemological Belief (TEB) was analyzed by using Winstep ver software. The result was summarized as follows. Dimensionality Analysis In Rasch analysis, a satisfactory dimensionality determined by raw variance explained by measures which should be more than 40% and unexplned variance in 1st contrast which should be 15. Table 1 shows that raw variance explained by measures was 56.5%, and unexplained variance in 1st contrast was 6.0 %. Table 1 Item dimensionality of TEB -- Empirical -- Modeled Total raw variance in observations = % 100.0% Raw variance explained by measures = Raw variance explained by persons = % % 42.8% 6.1% Raw Variance explained by items = % 36.7% Raw unexplained variance (total) = % 100.0% 57.2% Unexplned variance in 1st contrast = Unexplned variance in 2nd contrast = Unexplned variance in 3rd contrast = Unexplned variance in 4th contrast = Unexplned variance in 5th contrast = % 10.7% % 9.3% % 8.0% % 6.6% % 5.6% Reliability Analysis The questionnaire of Teacher of Epistemological Belief (TEB) contained 36 items. The criterion for accepting reliability in Rasch model (RM) is exceeding 0.50 (Bond & Fox, 2007). In addition, acceptable separation should be more than 2 (Fisher, 2007).Table 2 and 3 the show that the person and item reliability, person and item separation for TEB instrument. Table 2 indicates that the person reliability was 0.73 and person separation was 2.64.Table 3 shows that the item reliability was very high 0.98 and item separation was 7.85 which are acceptable.hence, the results of personand item reliability and person and item separation for TEB indicate satisfactory readability for the TEB instrument. > RJSSM: Volume: 05, Number: 09, January 2016 Page 108

4 Table 2. Person separation and reliability 100 MEASURED PERSON TOTAL MODEL INFIT OUTFIT SCORE COUNT MEASURE ERROR MNSQ ZSTD MNSQ ZSTD MEAN S.D MAX MIN REAL RMSE.24 TRUE SD.40 SEPARATION2.64PERSON RELIABILITY.73 MODEL RMSE.23 TRUE SD.41 SEPARATION 1.78 PERSON RELIABILITY.76 S.E. OF PERSON MEAN =.05 Table 3. Item separation and reliability 36 MEASURED ITEM 36 MEASURED ITEM TOTAL MODEL INFIT OUTFIT SCORE COUNT MEASURE ERROR MNSQ ZSTD MNSQ ZSTD MEAN S.D MAX MIN REAL RMSE.15 TRUE SD 1.17 SEPARATION 7.85 ITEM RELIABILITY.98 MODEL RMSE.14 TRUE SD 1.17 SEPARATION 8.22 ITEM RELIABILITY.99 S.E. OF ITEM MEAN =.20 Item Polarity and Item Fit Analysis Item polarity or point measure correlation (PTMEA Correlation) is the early detection of construct validity (Bond & Fox, 2007). This analysis was used to examine the relationship between the items in measuring the constructs that required. The good correlation values of items should be.20.as shown in table 4 there was no negative value and all PTMEA of each item is >.20. Table 4. Item Fit Analysis ENTRY TOTAL TOTAL MODEL INFIT OUTFIT PT-MEASURE EXACT MATCH NUMBER SCORE COUNT MEASURE S.E. MNSQ ZSTD MNSQ ZSTD CORR. EXP. OBS% EXP% ITEM B B B B B B B B B B B B B B B B B B B9 > RJSSM: Volume: 05, Number: 09, January 2016 Page 109

5 B B B B B B B B B B B B B B B B B MEAN S.D Calibration Scaling Analysis As shown in the Table 5, the most frequent answer is the scale of respondents ranking 4 which 1527 (42 %). The next grading scale that respondents selected was scale 3 of 998 (28%). The scale 2 had 686 (19%) respondents. While the least grading scale of least were scale 5 with 278 (8%) respondents, and scale of 1 of 111 (3%) respondents. Table 5. Calibration Scale Analysis CATEGORY OBSERVED OBSVD SAMPLE INFIT OUTFIT STRUCTURE CATEGORY LABEL SCORE COUNT % AVRGE EXPECT MNSQ MNSQ CALIBRATN MEASURE NONE ( -3.86) ( 4.40) > RJSSM: Volume: 05, Number: 09, January 2016 Page 110

6 P R O B A 55 B I 1 55 L I T Y * + O 2* F * R E S.2 +2 * P *5 44 O 333 ** N ** S.0 +************* *** **********************+ E Figure 1. Summary of the category structure on a scale gradation Conclusion This paper uses Rasch model analysis to test the construct validity and reliability of the TEB instrument as a measurement scale teachers epistemological belief. The findings of the Rasch analysis showed that questionnaire s items were valid and reliable and the items fit the model. Using the developed TEB questionnaire can be used to measure the epistemological beliefs of teachers. Acknowledgement I wish to express my sincere appreciation to my main supervisor, Professor Dr. MohamadNajib, and also to the 3 rd writer Samah Ali Mohsen. References Bond, T. G., & Fox, C. M. (2007).Applying the RM: Fundamental Measurement in the Human Sciences.Published by Lawrence Erilbaum Associations, Publishers, Marthwah, New Jersey, and London. Brunning, R. H.,Schraw, G., J., Norby, M.M., & R.R. (2004), Cognitive Psychology and Instruction (4 th ed). Upper Saddle River, NJ: Pearson Education. Crotty, M. (1998).The Foundations of the Social Research.Meaning and Perspective in the Research Process. London.Sage Publications. Fisher, Colin. 2007). Researching and Writing a Dissertation: A Guidebook for Business Students. NJ. Financial Times Prentice Hall. Fraenkel, J.R and Wallen, N.E. and Hyun, H.H. (2012).How to Design and Evaluate Research in Education. (8 th ed). New York.The McGraw-Hill Companies. Hamlyn, D.W. (1995). Epistemology, History of the Oxford Companion to Philosophy. Oxford. Oxford University Press. > RJSSM: Volume: 05, Number: 09, January 2016 Page 111

7 Hofer, B. K., &Pintrich, P. R. (1997).The Development of Epistemological Theories: Beliefs about Knowledge and Knowing and Their Relation to Learning. Review of Educational Research, 67, Johnson, Burke & Christensen, L. (2012).Educational Research.Quantitative, Qualitative, and Mixed Approaches.4 th Edition. California. SAGE Publications.Inc. Maynard, M. (1994).Methods, Practice, and Epistemology: the Debate about Feminism and Research Reseacrhing Women s Lives from Feminist Perspective. London.Taylor and Francis. MohamadNajib Abdul Ghafar. (2009). PrinsipAsasPenilaian Program Pendidikan.Skudai. Johor Bahru.UTM Penerbit. MohamadNajib Abdul Ghafar. (2011). PembinaandanAnalisisUjianBilikDarjah.2 nd Ed. Skudai. Johor Bahru.UTM Penerbit. Rasch, G. (1960). Probabilistic Models for some Intelligence and Attainment Tests.(Copenhagen, Danish Institute for Educational Research. Chicago: The University of Chicago Press Samah, AM.,MohamadNajib Abdul Ghafar.,Abdul Hafiz Hj Omar.,MonsuratMosaku.,Amar Ma ruf. (2014). Psychometric Properties on Lecturers Beliefs on Teaching Function:Rasch Model Analysis. Journal of International Education Studies.7(11).doi: /ies.v7n11p47 Schommer, M. (1990).Effects of Beliefs about the Nature of Knowledge on Comprehension.Journal of Educational Psychology, 82, Schommer, M. (1994).Synthesizing Epistemological Belief Research: Tentative Understanding and Provocative Confusions, Educational Psychology, Review, 6 (4), Perry, W. G. Jr. (1970). Forms of Ethical and Intellectual Development in the College Years: A scheme. New York: Holt, Rinehart & Winston. > RJSSM: Volume: 05, Number: 09, January 2016 Page 112