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The argument for preceding multiple analysis of variance (ANOVAS) with a multivariate analysis of variance (MANOVA) to control for Type I error is challenged. Several situations are discussed in which multiple ANOVAS might be conducted without the necessity of a preliminary MANOVA. Three reasons for considering a multivariate analysis are discussed: to identify outcome variable system constructs, to select variable subsets, and to determine variable relative worth. The analyses discussed in this article are those appropriate in research situations in which analysis of variance techniques are useful. These analyses are used to study the effects of treatment variables on outcome/response variables (in ex post facto as well as experimental studies). We speak of an univariate analysis of variance (ANOVA) when a single outcome variable is involved; when multiple outcome variables are involved, it is a multivariate analysis of variance (MANOVA). (Covariance analyses may also be included.) With multiple outcome variables, the typical analysis approach used in the group-comparison context, at least in the behavioral sciences, is to either (a) conduct multiple ANOVAs or (b) conduct a MANOVA followed by multiple ANOVAS. That these are two popular choices may be concluded from a survey of some prominent behavioral science journals. The 1986 issues of five journals published by the American Psychological Association were surveyed:

Articles published in several prominent educational journals were examined to investigate the use of data-analysis tools by researchers in four research paradigms: between-subjects univariate designs, between-subjects multivariate designs, repeated measures designs, and covariance designs. In addition to examining specific details pertaining to the research design (e.g., sample size, group size equality/inequality) and methods employed for data analysis, we also catalogued whether: (a) validity assumptions were examined, (b) effect size indices were reported, (c) sample sizes were selected based on power considerations, and (d) appropriate textbooks and/or articles were cited to communicate the nature of the analyses that were performed. Our analyses imply that researchers rarely verify that validity assumptions are satisfied and accordingly typically use analyses that are nonrobust to assumption violations. In addition, researchers rarely report effect size statistics, nor do they routinely perform power analyses to determine sample size requirements. We offer many recommendations to rectify these shortcomings. Data Analytic Practices 3 Statistical Practises of Educational Researchers:An Analysis of Their ANOVA, MANOVA and ANCOVA Analyses It is well known that the volume of published educational research is increasing at a very rapid pace. As a consequence of the expansion of the field, qualitative and quantitative reviews of the literature are becoming more common. These reviews typically focus on summarizing the results of research in particular areas of scientific inquiry (e.g., academic achievement or English as a second language) as a means of highlighting important findings and identifying gaps in the literature. Less common, but equally important, are reviews that focus on the research process, that is, the methods by which a research topic is addressed, including research design and statistical analysis issues.Methodological research reviews have a long history (e.g., Edgington, 1964; Elmore & Woehlke, 1988 Goodwin & Goodwin, 1985a, 1985bWest, Carmody, & Stallings, 1983).One purpose of these reviews has been the identification of trends in data-analytic practice. The documentation of such trends has a two-fold purpose: (a) it can form the basis for recommending improvements in research practice, and (b) it can be used as a guide for the types of inferential procedures that should be taught in methodological courses, so that students have adequate skills to interpret the published literature of a discipline and to carry out their own projects.One consistent finding of methodological research reviews is that a substantial gap often exists between the inferential methods that are recommended in the statistical research literature and those techniques that are actually adopted by applied researchers (Goodwin & Goodwin, 1985b;Ridgeway, Dunston, & Qian, 1993). The practice of relying on traditional methods of analysis is, however, dangerous. The field of statistics is by no means static; improveme...

The two problems for which a discriminant analysis is used-separation and classification-are reviewed. Issues related to the use and interpretation of a discriminant analysis are those pertaining to (a) distinguishing between a linear discriminant function and a linear classification function, (b) misusing stepwise discriminant analysis programs, (c) ordering variables and selecting variable subsets, (d) choosing a classification rule; (e) estimating true classification hit rates, (f) assessing classification accuracy, and (g) examining and using classification results.

Depending on how one interprets what an effect size index is, it may be claimed that its history started around 1940, or about 100 years prior to that. An attempt is made in this article to trace histories of a variety of effect size indices. Effect size bases discussed pertain to (a) relationship, (b) group differences, and (c) group overlap. Multivariable as well as univariate indices are considered in reviewing the histories.

Articles published in several prominent educational journals were examined to investigate the use of data-analysis tools by researchers in four research paradigms: between-subjects univariate designs, between-subjects multivariate designs, repeated measures designs, and covariance designs. In addition to examining specific details pertaining to the research design (e.g., sample size, group size equality/inequality) and methods employed for data analysis, we also catalogued whether: (a) validity assumptions were examined, (b) effect size indices were reported, (c) sample sizes were selected based on power considerations, and (d) appropriate textbooks and/or articles were cited to communicate the nature of the analyses that were performed. Our analyses imply that researchers rarely verify that validity assumptions are satisfied and accordingly typically use analyses that are nonrobust to assumption violations. In addition, researchers rarely report effect size statistics, nor do they routinely perform power analyses to determine sample size requirements. We offer many recommendations to rectify these shortcomings.

The purpose of the current study was to explore parent and child extratextual utterances during storybook and expository book sharing. Sixty‐two parents and their three‐ to four‐year‐old children from middle‐income families participated in the study. Dyads were videotaped on two occasions reading unfamiliar storybooks and expository books. Parent and child extratextual utterances were coded for their content, and parent utterances were coded for their utterance length and diversity of vocabulary. Content coding categories included feedback and acknowledgment, talk about print and book conventions, and talk about the book that was at lower levels of cognitive demand (Levels 1 and 2) and higher levels of cognitive demand (Levels 3 and 4). Within‐subjects comparisons across the two genres revealed that during storybook sharing, parents were more likely to read the entire text compared to expository book sharing. Expository book sharing was longer in duration and resulted in higher rates of extratextual utterances by both parents and children. During expository book sharing, parents used significantly higher rates of feedback utterances and utterances at Levels 1, 3, and 4; children used significantly higher rates of feedback utterances and utterances at Levels 3 and 4. The mean length of parent extratextual utterances was significantly longer in the expository book condition, and their talk contained significantly greater vocabulary diversity. These findings indicate that the genre of book can influence the amount of talk that takes place during book sharing, and it can alter the content, vocabulary diversity, and sentence length of extratextual utterances. إن هدف هذه الدراسة الحالية هو استقصاء الألفاظ ما بعد النص التي تجري بين الوالدين وأولادهما أثناء مشاركة القراءة القصصية والقراءة النصوصية. لقد اشترك في هذه الدراسة اثنان وستون والداً وأولادهم الذين تراوحت أعمارهم بين ثلاث إلى أرتع سنوات من أسر تنتمي إلى الطبقة الاجتماعية المتوسطة. وقد تم تصوير مجموعات من شخصين مرتين إبان قراءة كتب قصصية وكتب نصوصية غير مألوفة لهم. وتم تصنيف ألفاظ الوالد والولد من حيث المحتوى بينما تم تصنيف ألفاظ الوالد من حيث طول اللفظ وتنوع المفردات الذي أدى إلى تضمن تصانيف المحتوى ما يلي: التغذية الراجعة والاعتراف والقيام بمحادثة عن معارض كتب ومطبوعات وعن الكتاب الذي اندرج في المستويات المنخفضة من المتطلبات الذهنية (أي المستويين الأول والثاني) وأيضاً الذي اندرج في المستويات العالية من المتطلبات الذهنية (أي المستويين الثالث والرابع). 本研究旨在探索亲子间在分享式阅读故事性和阐述性图书时所涉及的文本以外的谈话。研究对象为62位来自中收入户的家长和他们年若三至四岁的子女。在共同阅读不熟知的故事性和阐述性图书的两种情况下，每对亲子之间的谈话，均予以录像记录。研究者根据亲子间文本以外的谈话内容区分作编码，亦根据家长的话语长短及语汇的广泛性作编码。内容编码类别包含：回馈、答谢、关于该读本的文字和形式的谈话，以及关于该读本的认知要求属低层次(第一阶和第二阶)和高层次(第三阶和第四阶)的谈话。 这两种体裁的受试者内比较检定结果显示：在分享阅读故事性图书时，家长把整个文本读完的可能性较大；在分享阅读阐述性图书时，这可能性则较小。阐述性图书分享阅读所持续的时间却较长，因此家长与子女间的文本以外的谈话也较多。在分享阅读阐述性图书时；家长所用的回馈言谈明显地较为频密，而且他们的谈话属于第一、二和第三阶的认知要求，他们子女所用的回馈言谈也明显地较为频密，他们的谈话属于第三和第四阶的认知要求。在分享阅读阐述性图书的情况下，家长的文本以外谈话的平均持续时间明显地较长，而他们谈话中所包含的语汇亦明显地较为多样化。这些研究结果显示：图书的体裁能影响在分享式阅读时亲子间谈话的多寡，也能影响亲子间谈话的内容、语汇是否多样化，以及文本以外谈话中句子的长短。 Cette étude avait pour but d'explorer les échanges verbaux e...

S Ninety‐six middle‐income parent‐child dyads were videotaped as they shared an unfamiliar book together. Parents' extratextual utterances were coded for content and entered into a cluster analysis in order to identify patterns in the variability in interaction style. Four clusters were revealed: (a) two small clusters of parents who provided many extratextual utterances during book sharing, but who differed with regard to the types of utterances used most frequently; (b) a cluster of parents who provided moderate numbers of utterances across all utterance types; and (c) a large cluster of parents who contributed minimal extratextual utterances during book sharing. Previous research has demonstrated that variability in parent interactions during book sharing is high. These results suggest that parents' utterances varied in systematic ways and that the predominant pattern within this sample was one of limited numbers of extratextual utterances during the sharing of an unfamiliar book. These findings have implications for the methods to best explore variability and the directions of future research.