Psychologist believe that memory of pictures is superior to memory for words. To test this hypothesis the psychologist performs an experiment in which students from an introductory psychology class are used as subjects. Eight randomly selected students view 30 slides with random nouns printed on them and another group of eight randomly selected students views 30 slides with actual pictures of the objects represented by the same nouns. Each slide contains either one picture or one noun and each slide is viewed for four seconds. After viewing all the slides subjects are given a recall test one hour later and the experimenter records the number of correctly remembered items. Use an alpha level of 0.05. The data are given in the table at the right.
a) What is the null hypothesis? Assume a directional hypothesis is warranted.
b) What is the null hypothesis assuming a non-directional hypothesis?
c) Using alpha = 0.05 1tail what is your conclusion
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# of pictures recalled
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# of nouns recalled
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18
|
12
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21
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9
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22
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21
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25
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17
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23
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16
|
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19
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10
|
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26
|
22
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15
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22
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