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Quantitative Techniques-II



                      Notes
                                           Example:
                                          “Is the current advertisement less effective than the proposed new advertisement”?

                                          A two-tailed test is appropriate, when the researcher has no reason to focus on one
                                           side of the issue.


                                           Example: “Are the two markets – Mumbai and Delhi different to test market a product?”
                                          A product is manufactured by a semi-automatic machine. Now, assume that the
                                           same product is manufactured by the fully automatic machine. This will be two-
                                           sided  test,  because  the  null  hypothesis  is  that  “the  two  methods  used  for
                                           manufacturing the product do not differ significantly”.
                                                   H   = µ  = µ
                                                      0    1   2
                                                  Sign of alternate hypothesis       Type of test
                                                            =               Two-sided
                                                            <               One-sided to right
                                                            >               One-sided to left

                                    12.2.4 Degree of Freedom

                                    It tells the researcher the number of elements that can be chosen freely.


                                           Example: a+b/2 =5. fix a=3, b has to be 7. Therefore, the degree of freedom is 1.

                                    12.2.5 Select Test Criteria

                                    If the hypothesis pertains to a larger sample (30 or more), the Z-test is used. When the sample is
                                    small (less than 30), the T-test is used.

                                    12.2.6 Compute

                                    Carry out computation.

                                    12.2.7 Make Decisions

                                    Accepting or rejecting of the null hypothesis depends on whether the computed value falls in the
                                    region of rejection at a given level of significance.




                                        Task  Discuss When Would You Prefer Two Tailed Test To One Tailed Test.

                                    Self Assessment

                                    Fill in the blanks:
                                    1.   A …………………..is a tentative proposition relating to certain phenomenon, which the
                                         researcher wants to verify when required.
                                    2.   A …………..is a statement about the population, whose credibility or validity the researcher
                                         wants to assess based on the sample.



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