Question

In: Statistics and Probability

A researcher studies the effect of the herbal stimulant Buttercup on short-term memory; she randomly divides...

A researcher studies the effect of the herbal stimulant Buttercup on short-term memory; she randomly divides a sample of 32 into four (4) groups.  Each group receives 0 mg, 500 mg, 1000 mg and 1500 mg respectively and is then tested on their short term memory span.  She finds:

                        NUMBER OF ITEMS REMEMBERED (MEMORY SPAN)

            0.0 mg             500 mg                        1000 mg                      1500 mg          

            8                      7                                  10                                4

            9                      6                                  15                                5

            7                      9                                  14                                2

            7                      8                                  14                                4

            8                      8                                  17                                3

            10                    6                                  13                                8

            6                      12                                9                                  7

            7                      9                                  12                                9

A.        State the Independent Variable and the Dependent Variable.

B.        State the null hypothesis in words and symbols.

C.        Compute the appropriate statistic.

D.        What is your decision?

E.         State the full conclusion in words, after computing, if necessary multiple comparisons.

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Expert Solution

orchestra answered 1 year ago
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