A regression test is a test where a previously known bug is tested for after a change. A retest is simply repeating a test.
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The F-statistic is a test on ratio of the sum of squares regression and the sum of squares error (divided by their degrees of freedom). If this ratio is large, then the regression dominates and the model fits well. If it is small, the regression model is poorly fitting.
In cases wherethe dependent variable can take any numerical value for a given set of independent variables multiple regression is used.But in cases when the dependent variable is qualitative(dichotomous,polytomous)then logistic regression is used.In Multiple regression the dependent variable is assumed to follow normal distribution but in case of logistic regression the dependent variablefollows bernoulli distribution(if dichotomous) which means it will be only0 or 1.
You can conclude that there is not enough evidence to reject the null hypothesis. Or that your model was incorrectly specified. Consider the exact equation y = x2. A regression of y against x (for -a < x < a) will give a regression coefficient of 0. Not because there is no relationship between y and x but because the relationship is not linear: the model is wrong! Do a regression of y against x2 and you will get a perfect regression!
regression testing is normally a set of automated scripts written by the test/automation team to test all previously existing functionality to make sure nothing has been broken.
A regression test is a test where a previously known bug is tested for after a change. A retest is simply repeating a test.
As the demand increases, so does the supply. You must have a data set of demand and supply measured on several days.
i know the facts. What is the reason? For your Regression?
The selection of test cases for regression testing:Requires knowledge on the bug fixes and how it affect the systemIncludes the area of frequent defectsIncludes the area which has undergone many/recent code changesIncludes the area which is highly visible to the usersIncludes the core features of the product which are mandatory requirements of the customerSelection of test cases for regression testing depends more on the criticality of bug fixes than the criticality of the defect itself. A minor defect can result in major side effect and a bug fix for an Extreme defect can have no or a just a minor side effect. So the test engineer needs to balance these aspects for selecting the test cases for regression testing.Read the Complete article at:http://www.onestopsoftwaretesting.com/2009/10/selecting-test-cases-for-regression.html
The marine regression analysis showed that the new subdivision was responsible for the coastline erosion.The wrinkle cream showed a regression in age lines.
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Regression are classified as - Full / Complete Regression -- Entire application is regressed - Regional regression -- Tests performed around defect fixes or code changes
Sampril Chatterjee has written: 'Regression analysis by Example' -- subject(s): Regression, analyse de
Regression testing is an iterative process executed throughout the software development and testing cycle. Regression testing focuses on previously tested aspects, features which were tested and found working, or bugs which were found and confirmed fixed, in earlier versions of the software. The purpose of regression testing is to make sure that those previously verified features still work. For example, consider a software release that includes two new features, A and B. While the developers are still working on feature B, test is already examining feature A. When A is found working as planned, testing proceeds to feature B, while regression testing affirms that nothing in feature B broke A.
The F-statistic is a test on ratio of the sum of squares regression and the sum of squares error (divided by their degrees of freedom). If this ratio is large, then the regression dominates and the model fits well. If it is small, the regression model is poorly fitting.
system testing is a kind of retesting where we can test whole system after integration. while regression testing is a process where we do the rerunning the test cases and check whether that re run doesnot affects the real environment.