Megfelelő kultúra = kiváló teljesítmény? (Appropriate culture = excellent performance?)

A szervezeti kultúra meghatározza azokat az alapvető értékeket, feltételezéseket, értelmezéseket és megközelítéseket, amelyek a szervezetet jellemzik. A definíciók sokszínűsége is bizonyítja, hogy a szervezeti kultúrában kifejeződik mindaz, amitől a szervezet egyedi. A vállalat teljesítményét számos tényező befolyásolja, ezek lehetnek külső, a vállalkozás által nagyrészt befolyásolhatatlan tényezők, de lehetnek belső, a vállalkozás által jelentősen befolyásolható tényezők. A kihívásokra adott egyedi, szervezetenként eltérő válaszok a vállalatok eltérő stratégiáiban, szervezeti felépítéseiben és szervezeti kultúráiban – mint a vállalat által befolyásolható tényezőkben – fejeződnek ki. A szerzők dolgozatukban egy empirikus kutatás eredményeinek egy részét mutatják be, amely az említett tényezők és a vállalati teljesítmény összefüggéseit tárja fel. Jelen tanulmány a vállalati teljesítmény és a szervezeti kultúra közti kapcsolatokat vizsgálja. A cikk elemzi, hogy melyek lehetnek azok a kulturális jellemzők, amelyek elősegíthetik a vállalati teljesítmény növelését. _________ The organizational culture determines the fundamental values, assumptions, interpretations and approaches which characterize the organization. The variability of definitions evidences that everything is expressed in organizational culture that makes organization specific. Corporate performance is influenced by numerous factors, these can be external ones not to be influenced by the company, and internal ones, being influenced by the company. The individual answers to challenges are expressed in different strategies, organizational structures and culture of companies as factors to be influenced by the companies. Authors present one part of the results of an empirical research, exploring connections between the mentioned factors and organizational cultures. The article analyses which cultural characteristics can enhance corporate performance.

The relative influence of social support, rehabilitation program participation, and inmate preincarceration characteristics on incarcerated substance abusers' perceptions of adjustment to community reintegration

This dissertation identifies, examines, and assesses the relative influence of identified empirically and conceptually relevant variables on incarcerated substance abusers' expectations of postrelease adjustment. A purposive sampling procedure was used to recruit 101 male and female substance-abusing offenders participating in prison- and jail-based drug treatment programs in south Florida. A 92-item survey questionnaire was used to collect basic demographic data; measure inmate preincarceration characteristics, social support, and rehabilitation program participation; and record archival data. Regression equations were developed utilizing ten different measures of the participants' expectations of their postrelease adjustment. Two equations yielded statistically significant F ratios; maintaining a stable living and maintaining abstinence. Twenty-two percent of the variance in respondents' expectations of maintaining a stable living was explained by preincarceration characteristics, social support, and rehabilitation program participation (F = 1.89; df = 13,87; p $<$.05). The only significant predictor variable was perception of social support (b = $-$.05; t = $-$3.6; p $<$.001). Twenty-three percent of the variance in respondents' expectations of maintaining abstinence from substances was explained by preincarceration characteristics, social support, and rehabilitation program participation (F = 2; df = 13,87; p $<$.05). Once again, the only significant predictor variable was perception of social support. The results of the analyses indicate that social support was the only important variable for understanding these respondents' efficacy expectations of postrelease abstinence and stable living. The results of this investigation demonstrate the complexity of the social support variable for prisoners, and identify social support as a potential rehabilitative resource for substance-abusing inmates. The results of this investigation underscore the importance of continued, detailed empirical study in order to understand and clarify how social support, efficacy expectations, and actual postrelease performance interrelate for this population of offenders.

Development of operational performance models for truck-lane restrictions on freeway corridors

Highways are generally designed to serve a mixed traffic flow that consists of passenger cars, trucks, buses, recreational vehicles, etc. The fact that the impacts of these different vehicle types are not uniform creates problems in highway operations and safety. A common approach to reducing the impacts of truck traffic on freeways has been to restrict trucks to certain lane(s) to minimize the interaction between trucks and other vehicles and to compensate for their differences in operational characteristics. ^ The performance of different truck lane restriction alternatives differs under different traffic and geometric conditions. Thus, a good estimate of the operational performance of different truck lane restriction alternatives under prevailing conditions is needed to help make informed decisions on truck lane restriction alternatives. This study develops operational performance models that can be applied to help identify the most operationally efficient truck lane restriction alternative on a freeway under prevailing conditions. The operational performance measures examined in this study include average speed, throughput, speed difference, and lane changes. Prevailing conditions include number of lanes, interchange density, free-flow speeds, volumes, truck percentages, and ramp volumes. ^ Recognizing the difficulty of collecting sufficient data for an empirical modeling procedure that involves a high number of variables, the simulation approach was used to estimate the performance values for various truck lane restriction alternatives under various scenarios. Both the CORSIM and VISSIM simulation models were examined for their ability to model truck lane restrictions. Due to a major problem found in the CORSIM model for truck lane modeling, the VISSIM model was adopted as the simulator for this study. ^ The VISSIM model was calibrated mainly to replicate the capacity given in the 2000 Highway Capacity Manual (HCM) for various free-flow speeds under the ideal basic freeway section conditions. Non-linear regression models for average speed, throughput, average number of lane changes, and speed difference between the lane groups were developed. Based on the performance models developed, a simple decision procedure was recommended to select the desired truck lane restriction alternative for prevailing conditions. ^

Black middle school students' perceptions of success and their influence on academic performance

The purpose of the study was to investigate the perceptions of success held by Black middle school students in a Miami-Dade County (FL) public school and how these perceptions influence academic performance. The study sought to determine if differences exist among African-American, Haitian-American, and Haitian immigrant subgroups of the Black student population. ^ The study combined qualitative and quantitative methodology in data collection and analysis. The qualitative data consisted of three focus group interviews. Using a semi-structured protocol, questions focused on the student's perceptions of the characteristics of successful people, definitions of success, behaviors associated with achieving success, and peer, family and school support. The quantitative data comprised the responses of 352 Black middle school students to the Inventory of Student Motivation (ISM) developed to measure mastery, performance and social goal orientations. Response similarities and differences were examined using a series of two-way ANOVAs on the success scales by gender and culture. A three-way repeated measures ANOVA was conducted on mastery, performance and social general goal scales by culture and gender. ^ The results of the ISM revealed no statistically significant differences among African-American, Haitian-American, and Haitian students in their mastery, performance or social goal orientations. All three cultural groups scored significantly high on the mastery goal scale. There was a significant effect for gender on the mastery general scale with the females being more concerned with mastery than the males. Qualitative focus group interview results included varying definitions of success. African-American and Haitian-American students defined success in materialistic terms. Haitian students defined success in scholastic achievement terms. All students indicated hard work, persistence and goal setting through completion as important to achieving success. Negative influences included peer pressure, teacher and societal expectations, and classroom environment. Parental reaction to low academic performance varied by culture. ^

A comparative analysis of self-determined evaluations of work performance and support needs by adults with mental retardation in supported work and in sheltered workshop environments

The purpose of this study was to determine if there was a difference in the self-determined evaluations of work performance and support needs by adults with mental retardation in supported employment and in sheltered workshop environments. The instrument, Job Observation and Behavior Scale: Opportunity for Self-Determination (JOBS: OSD; Brady, Rosenberg, & Frain, 2006), was administered to 38 adults with mental retardation from sheltered workshops and 32 adults with mental retardation from supported employment environments. Cross-tabulations with Chi-square tests and independent samples t-tests were conducted to evaluate differences between the two groups, sheltered workshop and supported work. Two Multivariate Analyses of Variance (MANOVAs) were conducted to determine the effect of work environment on Quality of Performance (QP) and Types of Support (TS) test scores and their subscales. ^ This study found that there were significant differences between the groups on the QP Behavior and Job Duties subscales. The sheltered workshop group perceived themselves as performing significantly better on job duties than the supported work group. Conversely, the supported work group perceived themselves to have better behavior than the sheltered workshop group. However, there were no significant differences between groups in their perception of support needs for the three subscales. ^ The findings imply that work environment affects the self-determined evaluations of work performance by adults with mental retardation. Recommendations for further study include (a) detailing the characteristics of supported work and sheltered workshops that support and/or discourage self-determined behaviors, (b) exploring the behavior of adults with mental retardation in sheltered workshops and supported work environments, and (c) analysis of the support needs for and understanding of them by adults with mental retardation in sheltered workshops and in supported work environments. ^

Controlled growth of carbon nanotubes for high performance nanoelectronics

Unique electrical and mechanical properties of single-walled carbon nanotubes (SWNTs) have made them one of the most promising candidates for next-generation nanoelectronics. Efficient utilization of the exceptional properties of SWNTs requires controlling their growth direction (e.g., vertical, horizontal) and morphologies (e.g., straight, junction, coiled). ^ In this dissertation, the catalytic effect on the branching of SWNTs, Y-shaped SWNTs (Y-SWNTs), was investigated. The formation of Y-shaped branches was found to be dependent on the composition of the catalysts. Easier carbide formers have a strong tendency to attach to the sidewall of SWNTs and thus enhance the degree of branching. Y-SWNTs based field-effect transistors (FETs) were fabricated and modulated by the metallic branch of the Y-SWNTs, exhibiting ambipolar characteristics at room temperature. A subthreshold swing of 700 mV/decade and an on/off ratio of 105 with a low off-state current of 10-13 A were obtained. The transport phenomena associated with Y- and cross-junction configurations reveals that the conduction mechanism in the SWNT junctions is governed by thermionic emission at T > 100 K and by tunneling at T < 100 K. ^ Furthermore, horizontally aligned SWNTs were synthesized by the controlled modification of external fields and forces. High performance carbon nanotube FETs and logic circuit were demonstrated utilizing the aligned SWNTs. It is found that the hysteresis in CNTFETs can be eliminated by removing absorbed water molecules on the CNT/SiO2 interface by vacuum annealing, hydrophobic surface treatment, and surface passivation. SWNT “serpentines” were synthesized by utilization of the interaction between drag force from gas flow and Van der Waals force with substrates. The curvature of bent SWNTs could be tailored by adjusting the gas flow rate, and changing the gas flow direction with respect to the step-edges on a single-crystal quartz substrate. Resistivity of bent SWNTs was observed to increase with curvature, which can be attributed to local deformations and possible chirality shift at curved part. ^ Our results show the successful synthesis of SWNTs having controllable morphologies and directionality. The capability of tailoring the electrical properties of SWNTs makes it possible to build an all-nanotube device by integrating SWNTs, having different functionalities, into complex circuits. ^

Improving storage performance through layout optimizations

Disk drives are the bottleneck in the processing of large amounts of data used in almost all common applications. File systems attempt to reduce this by storing data sequentially on the disk drives, thereby reducing the access latencies. Although this strategy is useful when data is retrieved sequentially, the access patterns in real world workloads is not necessarily sequential and this mismatch results in storage I/O performance degradation. This thesis demonstrates that one way to improve the storage performance is to reorganize data on disk drives in the same way in which it is mostly accessed. We identify two classes of accesses: static, where access patterns do not change over the lifetime of the data and dynamic, where access patterns frequently change over short durations of time, and propose, implement and evaluate layout strategies for each of these. Our strategies are implemented in a way that they can be seamlessly integrated or removed from the system as desired. We evaluate our layout strategies for static policies using tree-structured XML data where accesses to the storage device are mostly of two kinds—parent-to-child or child-to-sibling. Our results show that for a specific class of deep-focused queries, the existing file system layout policy performs better by 5–54X. For the non-deep-focused queries, our native layout mechanism shows an improvement of 3–127X. To improve performance of the dynamic access patterns, we implement a self-optimizing storage system that performs rearranges popular block accesses on a dedicated partition based on the observed workload characteristics. Our evaluation shows an improvement of over 80% in the disk busy times over a range of workloads. These results show that applying the knowledge of data access patterns for allocation decisions can substantially improve the I/O performance.

Analytical approximations to predict performance measures of manufacturing systems with job failures and parallel processing

Parallel processing is prevalent in many manufacturing and service systems. Many manufactured products are built and assembled from several components fabricated in parallel lines. An example of this manufacturing system configuration is observed at a manufacturing facility equipped to assemble and test web servers. Characteristics of a typical web server assembly line are: multiple products, job circulation, and paralleling processing. The primary objective of this research was to develop analytical approximations to predict performance measures of manufacturing systems with job failures and parallel processing. The analytical formulations extend previous queueing models used in assembly manufacturing systems in that they can handle serial and different configurations of paralleling processing with multiple product classes, and job circulation due to random part failures. In addition, appropriate correction terms via regression analysis were added to the approximations in order to minimize the gap in the error between the analytical approximation and the simulation models. Markovian and general type manufacturing systems, with multiple product classes, job circulation due to failures, and fork and join systems to model parallel processing were studied. In the Markovian and general case, the approximations without correction terms performed quite well for one and two product problem instances. However, it was observed that the flow time error increased as the number of products and net traffic intensity increased. Therefore, correction terms for single and fork-join stations were developed via regression analysis to deal with more than two products. The numerical comparisons showed that the approximations perform remarkably well when the corrections factors were used in the approximations. In general, the average flow time error was reduced from 38.19% to 5.59% in the Markovian case, and from 26.39% to 7.23% in the general case. All the equations stated in the analytical formulations were implemented as a set of Matlab scripts. By using this set, operations managers of web server assembly lines, manufacturing or other service systems with similar characteristics can estimate different system performance measures, and make judicious decisions - especially setting delivery due dates, capacity planning, and bottleneck mitigation, among others.

An agent-based model of team coordination and performance

This research is based on the premises that teams can be designed to optimize its performance, and appropriate team coordination is a significant factor to team outcome performance. Contingency theory argues that the effectiveness of a team depends on the right fit of the team design factors to the particular job at hand. Therefore, organizations need computational tools capable of predict the performance of different configurations of teams. This research created an agent-based model of teams called the Team Coordination Model (TCM). The TCM estimates the coordination load and performance of a team, based on its composition, coordination mechanisms, and job’s structural characteristics. The TCM can be used to determine the team’s design characteristics that most likely lead the team to achieve optimal performance. The TCM is implemented as an agent-based discrete-event simulation application built using JAVA and Cybele Pro agent architecture. The model implements the effect of individual team design factors on team processes, but the resulting performance emerges from the behavior of the agents. These team member agents use decision making, and explicit and implicit mechanisms to coordinate the job. The model validation included the comparison of the TCM’s results with statistics from a real team and with the results predicted by the team performance literature. An illustrative 26-1 fractional factorial experimental design demonstrates the application of the simulation model to the design of a team. The results from the ANOVA analysis have been used to recommend the combination of levels of the experimental factors that optimize the completion time for a team that runs sailboats races. This research main contribution to the team modeling literature is a model capable of simulating teams working on complex job environments. The TCM implements a stochastic job structure model capable of capturing some of the complexity not capture by current models. In a stochastic job structure, the tasks required to complete the job change during the team execution of the job. This research proposed three new types of dependencies between tasks required to model a job as a stochastic structure. These dependencies are conditional sequential, single-conditional sequential, and the merge dependencies.

A study on uncertain dynamic disaster management tasks, knowledge sharing, and task performance

Each disaster presents itself with a unique set of characteristics that are hard to determine a priori. Thus disaster management tasks are inherently uncertain, requiring knowledge sharing and quick decision making that involves coordination across different levels and collaborators. While there has been an increasing interest among both researchers and practitioners in utilizing knowledge management to improve disaster management, little research has been reported about how to assess the dynamic nature of disaster management tasks, and what kinds of knowledge sharing are appropriate for different dimensions of task uncertainty characteristics. ^ Using combinations of qualitative and quantitative methods, this research study developed the dimensions and their corresponding measures of the uncertain dynamic characteristics of disaster management tasks and tested the relationships between the various dimensions of uncertain dynamic disaster management tasks and task performance through the moderating and mediating effects of knowledge sharing. ^ Furthermore, this research work conceptualized and assessed task uncertainty along three dimensions: novelty, unanalyzability, and significance; knowledge sharing along two dimensions: knowledge sharing purposes and knowledge sharing mechanisms; and task performance along two dimensions: task effectiveness and task efficiency. Analysis results of survey data collected from Miami-Dade County emergency managers suggested that knowledge sharing purposes and knowledge sharing mechanisms moderate and mediate uncertain dynamic disaster management task and task performance. Implications for research and practice as well directions for future research are discussed.^

The relationship between staff perceptions of principal leadership and school performance

The climate of a school can be defined as the set of internal characteristics that distinguishes one school from another and influences the behavior of its members (Hoy & Hannum, 1997). Schools with a positive climate have been shown to positively impact students (Hoy, 1972). A principal’s leadership style influences the climate that, in turn, impacts student performance. ^ In this work, the researcher investigated Miami-Dade County Public Schools in order to determine if there was a relationship between instructional staff members’ perceptions of their school’s principals, a derivative of the district’s school climate studies, and their schools’ grades. ^ Eight School Climate Survey items were inter-correlated. The smallest intercorrelation was .83, which is still a large intercorrelation, and the largest intercorrelation was .96. Pearson’s correlation analysis (Healey, 2004) was run to determine the relationship between schools’ earned points and averaged survey responses. Survey items 8, 9, 12 and 13 had weak (less than .30) positive correlations to schools’ earned points. Survey items 7, 10, 11 and 14 had moderate (above .30) positive correlations to schools’ earned points. ^ The researcher created a composite variable (Pallant, 2007) from all the School Climate Survey responses. This composite variable, titled Principal Leadership Score, allowed the researcher to determine that approximately 9% of the variance in the points earned by schools in 2009 can be accounted for by how teachers in this study perceived the leadership of their principals. ^ This study’s findings of a moderate positive correlation between teachers’ perceptions of principal leadership and school performance supports earlier research linking school climate and school performance. Due to the fact that the leadership of the principal affects, either positively or negatively, the learning and working environment of students and teachers, it is recommended that principals use the eight School Climate Survey items examined within this study as guides (Pepper & Thomas, 2002). Through focusing on these survey items, principals may be propelled to self-identify their leadership strengths as well as leadership weaknesses.^

Salinity and Chlorophyll a as Performance Measures to Rehabilitate a Mangrove-Dominated Deltaic Coastal Region: the Ciénaga Grande de Santa Marta–Pajarales Lagoon Complex, Colombia

Salinity, water temperature, and chlorophyll a (chl-a) biomass were used as performance measures in the period 1999–2001 to evaluate the effect of a hydrological rehabilitation project in the Ciénaga Grande de Santa Marta (CGSM)–Pajarales lagoon complex, Colombia where freshwater diversions were initiated in 1995 and completed in 1998. The objective of this study was to evaluate how diversions of freshwater into previously hypersaline (>80) environments changed the spatial and temporal distribution of environmental characteristics. Following the diversion, 19 surveys and transects using a flow-through system were surveyed in the CGSM–Pajarales complex to continuously measure selected water quality parameters. Geostatistical analysis indicates that hydrology and salinity regimes and water circulation patterns in the CGSM lagoon are largely controlled by freshwater discharge from the Fundacion, Aracataca, and Sevilla Rivers. Residence times in the CGSM lagoon were similar before (15.5 ± 3.8 days) and after (14.2 ± 2.0 days) the rehabilitation project and indicated that the system is flushed regularly. In contrast, chl-a biomass was highly variable in the CGSM–Pajarales lagoon complex and not related to discharge patterns. Mean annual chl-a biomass (44–250 μg L−1) following the diversion project was similar to values recorded since the 1980s and still remains among the highest reported in coastal systems around the world owing to its unique hydrology regulated by the Magdalena River and Sierra Nevada de Santa Marta watersheds and the high teleconnection to the El Niño Southern Oscillation (ENSO). Our results confirm that the reduction in salinity in the CGSM lagoon and Pajarales complex during 1999–2000 was largely driven by high precipitation (2500 mm) induced by the ENSO–La Niña rather than by the freshwater diversions.

Development of safety performance functions for SafetyAnalyst applications in Florida

In 2010, the American Association of State Highway and Transportation Officials (AASHTO) released a safety analysis software system known as SafetyAnalyst. SafetyAnalyst implements the empirical Bayes (EB) method, which requires the use of Safety Performance Functions (SPFs). The system is equipped with a set of national default SPFs, and the software calibrates the default SPFs to represent the agency's safety performance. However, it is recommended that agencies generate agency-specific SPFs whenever possible. Many investigators support the view that the agency-specific SPFs represent the agency data better than the national default SPFs calibrated to agency data. Furthermore, it is believed that the crash trends in Florida are different from the states whose data were used to develop the national default SPFs. In this dissertation, Florida-specific SPFs were developed using the 2008 Roadway Characteristics Inventory (RCI) data and crash and traffic data from 2007-2010 for both total and fatal and injury (FI) crashes. The data were randomly divided into two sets, one for calibration (70% of the data) and another for validation (30% of the data). The negative binomial (NB) model was used to develop the Florida-specific SPFs for each of the subtypes of roadway segments, intersections and ramps, using the calibration data. Statistical goodness-of-fit tests were performed on the calibrated models, which were then validated using the validation data set. The results were compared in order to assess the transferability of the Florida-specific SPF models. The default SafetyAnalyst SPFs were calibrated to Florida data by adjusting the national default SPFs with local calibration factors. The performance of the Florida-specific SPFs and SafetyAnalyst default SPFs calibrated to Florida data were then compared using a number of methods, including visual plots and statistical goodness-of-fit tests. The plots of SPFs against the observed crash data were used to compare the prediction performance of the two models. Three goodness-of-fit tests, represented by the mean absolute deviance (MAD), the mean square prediction error (MSPE), and Freeman-Tukey R2 (R2FT), were also used for comparison in order to identify the better-fitting model. The results showed that Florida-specific SPFs yielded better prediction performance than the national default SPFs calibrated to Florida data. The performance of Florida-specific SPFs was further compared with that of the full SPFs, which include both traffic and geometric variables, in two major applications of SPFs, i.e., crash prediction and identification of high crash locations. The results showed that both SPF models yielded very similar performance in both applications. These empirical results support the use of the flow-only SPF models adopted in SafetyAnalyst, which require much less effort to develop compared to full SPFs.

The impact of *experience, industry characteristics, and individual differences on audit risk and the extent of testing decisions: An empirical investigation

The first part of the study examined the effect of industry risk changes on perceived audit risk at the financial statement level and whether these changes depended on individual differences such as experience and tolerance for ambiguity. ^ Forty-eight auditors from two offices of one of the “Big 5” CPA firms participated in this study. The ANOVA results supported the effect of industry risk in the assessment of audit risk at the financial statement level. Higher industry risk was associated with higher perceived audit risk. Tolerance for ambiguity was also significant in explaining the changes in the assessment of audit risk. Auditors with a high tolerance for ambiguity perceived lower audit risk than auditors with a low tolerance for ambiguity. Although ANOVA results did not find experience to be significant, a t-test for experience showed it to be marginally significant and inversely related to audit risk. ^ The second part of this study examined whether differences in perceived audit risk at the financial statement level altered the extent, nature or timing of the planned auditing procedures. The results of the MANOVA suggested an overall audit risk effect at the financial statement level. Perceived audit risk was significant in explaining the variation in the number of hours planned for the total cycle and the number of hours p1anned for the tests of balances and details. Perceived audit risk was not significant in determining the analytical review procedures planned, but assessed inherent risk at the cycle level was significant. The higher the inherent risk the more analytical procedures were planned. Perceived audit risk was not significant in explaining the timing of the procedures, but individual differences were significant. The results showed that experienced auditors and those with a high tolerance for ambiguity were less likely to postpone the performance of the interim procedures or the time at which the majority of audit work would be done. ^

School segregation and educational performance in a multicultural society: The case of Miami -Dade County, Florida

One of the most important goals of American educational institutions over the past 47 years has been the desegregation of pubic schools. This goal reflected the Supreme Court's decision in Brown v. Board of Education that segregated schools are inherently unequal and deny segregated minority students equal educational opportunities as mandated by the United States Constitution. This study examined the extent, nature, and causes of segregation in the Miami-Dade County Public Schools and the effects of segregation on the educational performance of minority students. ^ Research questions were analyzed using demographic data from the United States Census Bureau, the Metro-Dade County Planning Department, the United States Commission on Civil Rights, the United States Department of Education, and the Miami Dade County Public Schools. The extent of residential and school segregation in MiamiDade County was measured using the Dissimilarity Index. Historical and sociological literature were analyzed to explain the causes of school segregation, the socioeconomic characteristics of segregated minority students, and the relationship between school segregation and equal educational opportunities. A causal-comparative research method was chosen because it is the most appropriate method to compare the educational performance of minority students in segregated schools with the educational performance of minority students in desegregated schools. ^ The results of this study demonstrates that there is a high degree of residential and school segregation in Miami-Dade County, Florida. Furthermore, the Miami-Dade County Public Schools are characterized by a high degree of socioeconomic segregation. This is significant considering that the socioeconomic status of a student's peers is, after the student's family background, the most influential factor in determining academic performance. Clearly, schools and other social institutions must continue efforts to throughly desegregate the school district and improve minority student academic performance. A racially and economically desegregated school system would constitute an important component in Miami-Dade County's efforts to provide equal educational opportunities to all students. ^