Observational study, Advanced Statistics

Observational study is the study in which the objective is to discover cause-and-effect relationships but in which it is not feasible to use the controlled experimentation, in the sense of being able to impose process or treatments whose effects it is desired to discover, or to allocate the subjects at random to different measures. Surveys and most epidemiological studies come into this class. As the investigator does not control assignment of treatments there is no means to ensure that similar subjects receive different treatments. The classical instance of such a study that the successfully uncovered evidence of the important causal relationship is the smoking and lung cancer investigation of Doll and Hill. 

Posted Date: 7/30/2012 7:30:11 AM | Location : United States







Related Discussions:- Observational study, Assignment Help, Ask Question on Observational study, Get Answer, Expert's Help, Observational study Discussions

Write discussion on Observational study
Your posts are moderated
Related Questions
The act of combining data from heterogeneous sources with the intent of extracting information that would not be available for any single source in isolation. An example is the com

Bayes factor : A summary of evidence for the modelM1 against the another modelM0 provided by the set of data D, which can be used in the model selection. Given by the ratio of post

Item-total correlation is an  extensively used method for checking the homogeneity of the scale made up of number of items. It is simply the Pearson's product moment correlation c

The Null Hypothesis - H0:  There is no heteroscedasticity i.e. β 1 = 0 The Alternative Hypothesis - H1:  There is heteroscedasticity i.e. β 1 0 Reject H0 if Q = ESS/2 >

a sequence of numbers consist of six 6''s seven 7''s eight 8''s nine 9''s ten 10''s what is the arithmetic mean?

Technically the multivariate analogue of the quasi-likelihood with the same feature that it leads to consistent inferences about the mean responses without needing specific supposi

5. Packages from a machine a normally distributed with a mean 200g and its standard deviation 2grams. Find the probability that a package from the machine weighs a) Less than

Graduation is the term is employed most often in the application of the actuarial statistics to denote procedures by which the set or group of observed probabilities is adjusted t

The growth in bad debt expense for Johnston office supply Company over this time period.If this rate continues,estimate the percentage increase in bad debts for 1997,relative to 19

The Null Hypothesis - H0: There is no autocorrelation The Alternative Hypothesis - H1: There is at least first order autocorrelation Rejection Criteria: Reject H0 if LBQ1 >