Meta-Analysis and the Planning of Future Studies
A recent meta-analysis on ability grouping by Kulik and Kulik (1982) was used as an example to demonstrate how a researcher might plan for adequate sample sizes and power in future research. Data sufficient to estimate minimum sample sizes and power were gleaned from the meta-analysis study or obtained from its authors. Distributions of harmonic mean sample size and estimated power were displayed and ranges of estimates for each were presented using effect sizes from the meta-analysis with fixed alpha. Although effect sizes were relatively symmetric about .10, power and harmonic mean sample sizes were quite skewed. Recommendations for major professors, re- searchers and journal editors were made to assist in the evaluation and planning of research.
Mfano wa utafiti wa meta-uchambuzi wa kulinganisha uwezo wa kulinganisha na kulinganisha uwezo wa kulinganisha na kulinganisha uwezo wa kulinganisha na kulinganisha uwezo wa kulinganisha na kulinganisha ni mfano wa utafiti wa meta-uchambuzi wa kulinganisha na kulinganisha uwezo wa kulinganisha na kulinganisha. Takwimu za kutosha kukadiria ukubwa wa sampuli ya chini na nguvu zilipatikana kutoka kwa utafiti wa meta-uchambuzi au kupatikana kutoka kwa waandishi wake. Ugawaji wa wastani wa sampuli ya harmoniki na nguvu ya makadirio ilionyeshwa na safu za makadirio kwa kila moja zilionyeshwa kwa kutumia ukubwa wa athari kutoka kwa uchambuzi wa meta na alpha iliyowekwa. Ingawa ukubwa wa athari ulikuwa sawa na 0.10, nguvu na ukubwa wa sampuli ya wastani wa harmoniki zilikuwa na ubaguzi. Mapendekezo kwa ajili ya maprofesa wakuu, watafiti na wahariri wa jarida yalifanywa kusaidia katika tathmini na mipango ya utafiti.