Question

1. Subjects in a verbal learning study learned two equivalently difficult words to a criterion of one complete trial through the list without error. In one condition, the subjects were tested with a vocal of the song “Tomorrow” from the musical Annie as background music; in the other condition, the song and its loudness were the same, but the music was an instrumental arrangement. The dependent variable was trials to criterion. Conditions were counterbalanced so that half of the subjects had the instrumental condition first and half had the vocal first. Were there differences in learning under the two different conditions?

Subject                              Vocal                          Instrumental

            1                                  18                                            13

            2                                  13                                            9

            3                                  22                                            17

            4                                  9                                              13

            5                                  10                                            10

            6                                  18                                            14

            7                                  16                                            21

            8                                  18                                            11

            9                                  8                                              5

            10                                19                                            13

            11                                22                                            16

            12                                16                                            11

            13                                25                                            19

            14                                20                                            15

            15                                9                                              7

Independent variable/s:

Levels of independent variable/s:

Dependent variable/s:

Test to use:

Does the type of background music affect the number of trials needed to learn a list of words?

Value of YOUR test statistic (from your print-out):

p-value from test:

Show all steps with answers so I can understand! Thanks

Answer 1

1) Both vocal and Instrumental are independent variable.

2) Degrees of freedom of both the variables are

df1=14 (n1-1)

df2=14 (n2-1)

3) Dependent variable is subjects in verbal larning study.

4) Independent sample t- test should be used.

The independent samples t-test is a test that is used to compare two groups on the mean value of a continuous normally distributed variable.

5) Does the type of background music affect the number of trials needed to learn a list of words. For this we set up the hypothesis as follows :

H0: The type of background music do not affects the number of trials needed to learn a list of words.

H1:The type of background music affects the number of trials needed to learn a list of words.

6) TEST STATISTIC

7) p- value