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Imagine that we have a normal distribution of Exam scores for Psychology 210 with a mean of 75 and a standard deviation of 12. If I randomly drew a score of 97, would this be surprising? Explain your answer.

Imagine that every X value in a positively skewed distribution is transformed into a z-score. Answer the questions below about the resulting distribution of z-scores. a) Shape = b) Mean = c) Standard deviation =    

Based on the frequency polygon displayed below, how many students obtained a test score of 65?

If the SS = 15 with a sample size of 3, what is the standard deviation?

Is there a problem with this graph? Explain.                                                            Fiscal Quarter

Imagine that we have a normal distribution of Exam scores for Psychology 210 with a mean of 75 and a standard deviation of 10. If I randomly drew a score of 53, would this be surprising? Explain your answer.

What is the mean of the number set: 1, 2, 3, 4, 5, 10, 11, 100?

The Bigfoot Field Researchers Organization (www.bfro.net) maintains a database of bigfoot/Sasquatch sightings and related reports. According to the BFRO database as of January 2011 the mean number of reports per county in the state of Washington is 12.59 (standard deviation = 14.19). Here are the z-scores for three specific counties: Whitman County: z = -0.89    Cowlitz County: z = -0.03      Skamania County: z = +2.78   Which of these three counties is least representative of the typical county in Washington in terms of the number of Bigfoot reports?

A researcher conducts an experiment to determine whether moderate doses of St. John’s wort have any effect on the memory of college students.  For this study, what is the independent variable?

a) What is the main purpose of a z-score (i.e., what does it tell us?)? b) Imagine that your friend tells you her z-score on an extroversion scale is -0.50. What does this mean? Your interpretation of this score does not need to be long, but it should fully explain the score.