Short term memory capacity.

1. A researcher conducted a study to see if a new drug "Drug X" can impact short-term memory capacity. The researcher asked 16 participants to complete ten memory tasks after taking the Drug X. Participants' score on each memory task can be found in the SPSS data file called "memory.sav". (a) Please compute a total test score for each participant by summing their scores for the ten memory tasks. Prepare a boxplot and tell if there are any outliers for the total test score. If there are any, please report the ID numbers associated with the outliers, remove them from the dataset and prepare a new boxplot for the researcher. (3 points) (b) Based on the final dataset you got in part (a) Use SPSS to compute the sample mean. You have to report the sample mean. Correct your answers to 2 decimal places please. Please also paste the SPSS output table as the answer. (c) The population mean of the total score is 50.00 with a standard deviation of 10.00, and is normally distributed. Suppose that the researcher wanted to know if there was any difference between the observed sample mean and the population mean. What statistical method should be used? (d) Please write down the two statistical hypotheses (e) Based on the final dataset you got in part (a) (i.e. data with no outliers), help the researcher to conduct the test that you have suggested in part (c). Report the respective statistical evidence and draw the conclusion about the study. The alpha level for the test should be .05. (6 points) (f) The researcher decided to conduct the study again with another sample with similar sample size (n = 18). A sample mean of 43.76 was obtained. Please conduct the same test you have conducted in part (e) and report the results. (g) If you were a statistical consultant, would you suggest that Drug X is effective in enhancing short-term memory capacity, based on the results reported in parts (e) and (f)? Why? Online - Contact support The researcher asked 16 participants to complete ten memory tasks after taking the Drug X. Participants' score on each memory task can be found in the SPSS data file called "memory.sav". (a) Please compute a total test score for each participant by summing their scores for the ten memory tasks. Prepare a boxplot and tell if there are any outliers for the total test score. If there are any, please report the ID numbers associated with the outliers, remove them from the dataset and prepare a new boxplot for the researcher. (b) Based on the final dataset you got in part (a) (i.e. data with no outliers), please use SPSS to compute the sample mean. You have to report the sample mean. Correct your answers to 2 decimal places please. Please also paste the SPSS output table as the answer. (c) The population mean of the total score is 50.00 with a standard deviation of 10.00, and is normally distributed. Suppose that the researcher wanted to know if there was any difference between the observed sample mean and the population mean. What statistical method should be used? (2 points) (d) Please write down the two statistical hypotheses (e) Based on the final dataset you got in part (a) (i.e. data with no outliers), help the researcher to conduct the test that you have suggested in part (c). Report the respective statistical evidence and draw the conclusion about the study. The alpha level for the test should be .05. (6 points) (f) The researcher decided to conduct the study again with another sample with similar sample size (n = 18). A sample mean of 43.76 was obtained. Please conduct the same test you have conducted in part (e) and report the results. (g) If you were a statistical consultant, would you suggest that Drug X is effective in enhancing short-term memory capacity, based on the results reported in parts (e) and (f)? Why?                                

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