Question

13. A researcher assesses 7 students on test anxiety using blood pressure as a measure (the higher the blood pressure, the greater the anxiety); she then assesses the same subjects again after they view a 2-hour videotape on "relaxation techniques under stress".  The results, average systolic blood pressure, were:

Subject        Before              After              

1                120                 110              

2                160                 110              

3                124                 100              

4                135                  99              

5                170                 115              

6                143                 106              

7                188                  89               

            1. State the independent and dependent variables.

            2. State the Null Hypothesis in words and symbols.

            3. Compute the appropriate statistic.

            4. What is the decision?

            5. State the full conclusion in words.

14. A developmental psychologist prepares a video tape which demonstrates the “conservation of matter”.  She selects 8 young children from a day care and first tests them on this type of problem (that matter is the same volume regardless of shape) and records the number of correct responses.  She then shows the video tape and re-measures their ability to solve these problems.  Below are the results:

# correct                                  # correct

Child               before tape                              after tape

1                      3                                              8

2                      0                                              6

3                      6                                              4

4                      2                                              8

5                      9                                              10

6                      8                                              6

7                      6                                              2

8                      5                                              10

1. State the independent and dependent variables.
2. State the Null Hypothesis in words and symbols
3. Compute the appropriate statistic
4. What is the decision?
5. State the Full conclusion in words.

Answer 1

1. Let is denote the difference

d = systolic blood pressure before - systolic blood pressure after

Conclusion in context of problem :

There is sufficient evidence to support the claim that  2-hour videotape on "relaxation techniques under stress" significantly reduce the blood pressure.

2.Let us denote the difference

d = correct responses before tape - correct responses after tape

Conclusion in context of problem :

There is not sufficient evidence to conclude that videotape has significant effect on the ability to solve these problems.