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NCES: 98032 February 1998 |
The sample of elementary schools for the FRSS survey on parent involvement was selected from the 1993-94 NCES Common Core of Data (CCD) Public School Universe File. Over 84,000 public schools are contained in the CCD universe file, of which 60,000 are elementary schools. For this survey, elementary schools are defined as schools beginning with grade 6 or lower and having no grade higher than 8. Special education, alternative, schools not classified by grade span, and "combined" schools that house both elementary and secondary grades were excluded from the survey. A stratified sample of 900 schools was selected from the elementary school frame. To select the sample, the frame of schools was stratified by concentration of poverty in the school, as determined by the percentage of students eligible for free or reduced-price lunch. 2 Within these primary strata, schools were also sorted by enrollment size 3 and then by urbanicity. 4 The sample sizes were then allocated to the primary strata in rough proportion to the aggregate square root of the enrollment of schools in the stratum. The use of the square root of enrollment to determine the sample allocation is efficient for estimating both categorical school-level characteristics (e.g., number or percentage of schools that have voluntary written agreements with parents) and quantitative characteristics related to the size of the school (e.g., the number of families that received home visits from school staff). The sample size was large enough to permit limited analysis of the questionnaire (along one dimension) by the four regions, four urbanicity levels, three enrollment size categories, three levels of poverty concentration, and four categories of minority enrollments. However, because of the relatively small sample size, it is difficult to separate the independent effects of each characteristic (Table A-1, A-2, and A-3).
In early April 1996 questionnaires were mailed to 900 elementary school principals. The principal was asked either to complete the questionnaire or to have it completed by the person in the school who was most knowledgeable about parent involvement in the school. Telephone followup of nonrespondents was initiated in late April, and data collection was completed by June 1996. Five schools were found to be ineligible, and a total of 810 schools completed the survey. Thus, the unweighted final response rate was 91 percent. The weighted final response was 92 percent.
The response data were weighted to produce national estimates. The weights were designed to adjust for the variable probabilities of selection and differential nonresponse. The findings in this report are estimates based on the sample selected and, consequently, are subject to sampling variability.
The survey estimates are also subject to nonsampling errors that can arise because of nonobservation (nonresponse or noncoverage) errors, errors of reporting, and errors made in collection of the data. These errors can sometimes bias the data. Nonsampling errors may include such problems as the differences in the respondents' interpretation of the meaning of the questions; memory effects; misrecording of responses; incorrect editing, coding, and data entry; differences related to the particular time the survey was conducted; or errors in data preparation. While general sampling theory can be used in part to determine how to estimate the sampling variability of a statistic, nonsampling errors are not easy to measure and, for measurement purposes, usually require that an experiment be conducted as part of the data collection procedures or that data external to the study be used. To minimize the potential for nonsampling errors, the questionnaire was pretested with public school principals like those who completed the survey. During the design of the survey and the survey pretest, an effort was made to check for consistency of interpretation of questions and to eliminate ambiguous items. The questionnaire and instructions were extensively reviewed by the National Center for Education Statistics. Manual and machine editing of the questionnaire responses were conducted to check the data for accuracy and consistency. Cases with missing or inconsistent items were recontacted by telephone. Data were keyed with 100 percent verification.
The standard error is a measure of the variability of estimates due to sampling. It indicates the variability of a sample estimate that would be obtained from all possible samples of a given design and size. Standard errors are used as a measure of the precision expected from a particular sample. If all possible samples were surveyed under similar conditions, intervals of 1.96 standard errors below to 1.96 standard errors above a particular statistic would include the true population parameter being estimated in about 95 percent of the samples. This is a 95 percent confidence interval. For example, the estimated percentage of public elementary schools reporting that they sponsored an open house is 97 percent, and the estimated standard error is 0.8 percent. The 95 percent confidence interval for the statistic extends from [97- (0.8 x 1.96) to 97 + (0.8 x 1.96)], or from 95.4 to 98.6.
Estimates of standard errors for this report were computed using a technique known as jackknife replication method. Standard errors for all of the estimates are presented in the tables. All specific statements of comparison made in this report have been tested for statistical significance through t-tests adjusted for multiple comparisons using the Bonferroni adjustment, and they are significant at the 95 percent confidence level or better.
The survey was performed under contract with Westat, using the NCES Fast Response Survey System (FRSS). Westat's Project Director was Elizabeth Farris, and the Survey Manager was Nancy Carey. Judi Carpenter, now retired, was the NCES Project Officer during data collection. Shelley Burns is the current NCES Project Officer, and Edith McArthur is the FRSS Planning Officer. The data were requested by Oliver Moles, National Institute on the Education of At-Risk Students, and Mary Rollefson of the National Center for Education Statistics, Office of Educational Research and Improvement, U.S. Department of Education, and by the National Education Goals Panel.
This report was reviewed by the following individuals:
Outside NCES
Inside NCES
For more information about the Fast Response Survey System or the Survey on Family and School Partnerships in Public Schools, K-8, contact Shelley Burns, Data Development and Longitudinal Studies Group, National Center for Education Statistics, Office of Educational Research and Improvement. This and other NCES reports are available on the Internet at http://nces.ed.gov/pubsearch.
Terms Defined on the Survey Questionnaire
Advisory Group or Policy Council - A committee that includes parents, separate from any parent-teacher organization, designed to address school policy issues and make recommendations to school personnel.
Child care programs - Daily programs that provide recreational or educational activities to students at the school outside of normal school hours.
Homework helpline - A school-sponsored telephone service that provides information about students' homework assignments to parents and students.
Sample Universe and Classification Variables
Urbanicity - based on the locale codes as defined in the Common Core of Data (CCD):
City - a central city of a Metropolitan Statistical Area (MSA).
Urban fringe - a place within an MSA of a central city, but not primarily its central city.
Town - a place not within an MSA, but with a population greater than or equal to 2,500 and defined as urban by the U.S. Bureau of the Census.
Rural - a place with a population less than 2,500 and defined as rural by the U.S. Bureau of the Census.
Geographic Region - as defined by the National Assessment of Educational Progress (NAEP):
Northeast - Connecticut, Delaware, District of Columbia, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont.
Southeast - Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, and West Virginia.
Central - Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin.
West - Alaska, Arizona, California, Colorado, Hawaii, Idaho, Montana, Nevada, New Mexico, Oklahoma, Oregon, Texas, Utah, Washington, and Wyoming.
Size of Enrollment The number of students enrolled at the school, based on data in the 1993-94 CCD file.
Percent Minority Enrollment The percent of students enrolled in the school whose race or ethnicity is classified as one of the following: American Indian or Alaskan Native, Asian or Pacific Islander, Black, or Hispanic, based on data in the 1993-94 CCD file.
Poverty Concentration
The percent of students at the school eligible for free or reduced-price lunch, based on responses to question 22 on the survey questionnaire.
2 Categories used in sampling for the percent of students eligible for free or reduced-price lunch were: 0-24.9 percent; 25-49.9 percent; 50-74.9 percent; 75 percent or more; missing.
3 Categories used in sampling for enrollment size were: less than 300; 300-499; 500-999; 1,00- 1,499; 1,500 or more.
4 Categories used in sampling for urbanicity were: city; urban fringe; town; rural.