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ANCOVA in Counseling & Behavioral Research

  ANCOVA ANCOVA is a procedure like ANOVA except researchers can study the effects of one or more independent variables on a dependent variable after adjusting for other variables, called covariates , which were not a primary focus of the study. The letter C in ANCOVA stands for covariate . There can be several covariates in a study. In testing for differences among groups experiencing different leadership styles, we could study the effects on employee satisfaction after adjusting for a covariate of years of employment. A key word in ANCOVA studies is adjusting . Analysts adjust the scores based on information about the covariate before testing for significant differences. Basic features of an ANCOVA: Independent or grouping Variable = 1 or more Dependent or criterion Variable = 1 Covariates = 1 or more An  F  test indicates significance overall and for specific effects or relationships. A commonly reported measure of effect size is eta squared. A  p  value reveals the probabilit

ANOVA in Counseling & Psychology Research

There are several types of ANOVA procedures. The term ANOVA refers to Analysis of Variance . Variance is a statistical term we will review later. Variance refers to differences, so the ANOVA procedures examine differences in scores among groups of people who complete a survey, a test, or produce a scorable response. For example, an ANOVA can be used to assess the effects of three temperatures on math. The Independent Variable is temperature varies three ways (75, 85, 95 degrees F). The dependent variable is math. The dependent measure of math is a math test. When there is only one independent variable (IV), the ANOVA is called a one-way ANOVA. If there are two IVs the ANOVA is a two-way ANOVA, and so forth. It is rare to go beyond a four-way because the interpretation of interactions is complicated. The ANOVA procedure is usually reported with an F value. The larger the F value, the more likely it is that the differences the researchers found are not due to chance. There may be s

MANOVA in Counseling & Behavioral Sciences

  MANOVA MANOVA is the abbreviation for Multivariate Analysis of Variance . The M stands for multivariate and refers to the presence of more than one dependent variable. A MANOVA may have one or more independent variables and two or more dependent variables. For example, we could examine the effects of different presenters and different forgiveness programs on forgiveness and compassion. Studies with three to four independent variables and three to four dependent variables can be difficult to interpret because many interactions are possible. Independent or grouping Variable = 1 or more Dependent or criterion Variable = 2 or more Overall tests are used to determine significant effects or differences among the grouping variables. An  F  test indicates significance overall and for specific effects or relationships. A commonly reported measure of effect size is eta squared. A  p  value reveals the probability of a significant relationship-- one that is not due to chance factors. Read m