Search results
Results from the WOW.Com Content Network
A statistical significance test starts with a random sample from a population. If the sample data are consistent with the null hypothesis, then you do not reject the null hypothesis; if the sample data are inconsistent with the null hypothesis, then you reject the null hypothesis and conclude that the alternative hypothesis is true. [3]
In scientific writing, IMRAD or IMRaD (/ ˈ ɪ m r æ d /) (Introduction, Methods, Results, and Discussion) [1] is a common organizational structure for the format of a document. IMRaD is the most prominent norm for the structure of a scientific journal article of the original research type.
The major Neyman–Pearson paper of 1933 [11] also considered composite hypotheses (ones whose distribution includes an unknown parameter). An example proved the optimality of the (Student's) t-test, "there can be no better test for the hypothesis under consideration" (p 321). Neyman–Pearson theory was proving the optimality of Fisherian ...
Comparative research is a research methodology in the social sciences exemplified in cross-cultural or comparative studies that aims to make comparisons across different countries or cultures. A major problem in comparative research is that the data sets in different countries may define categories differently (for example by using different ...
When there may exist heterogeneous treatment effects across groups, the LATE is unlikely to be equivalent to the ATE. In one example, Angrist (1989) [16] attempts to estimate the causal effect of serving in the military on earnings, using the draft lottery as an instrument. The compliers are those who were induced by the draft lottery to serve ...
Many significance tests have an estimation counterpart; [26] in almost every case, the test result (or its p-value) can be simply substituted with the effect size and a precision estimate. For example, instead of using Student's t-test, the analyst can compare two independent groups by calculating the mean difference and its 95% confidence ...
The table shown on the right can be used in a two-sample t-test to estimate the sample sizes of an experimental group and a control group that are of equal size, that is, the total number of individuals in the trial is twice that of the number given, and the desired significance level is 0.05. [4] The parameters used are:
Difference in differences (DID [1] or DD [2]) is a statistical technique used in econometrics and quantitative research in the social sciences that attempts to mimic an experimental research design using observational study data, by studying the differential effect of a treatment on a 'treatment group' versus a 'control group' in a natural experiment. [3]