assistant
Moonpie
assistant.docxChapter 4
1. An additional research assistant has been hired to help with basic grading and statistical analyses. The new assistant is very eager, but is perplexed by the mean calculated below. Help the new assistant debug these calculations to determine what, if anything, went awry.
Grades f fx
80 5 400
75 9 300
70 4 280
65 5 325
55 2 275
90 4 360
95 3 285
100 2 200
n = 8 Σ = 2425
2. Use the following data set, calculate the mean, identify the mode, and spot the median.
# Homicides 2001
Cork........... 5
Cornwall..... 3
York............ 4
Middleton..... 11
Bloomington 6
Normal...... 2
Riverton... 7
Manchac... 1
Rooston..... 9
3. Take the data set below and calculate the mean, median, and mode.
# Homicides 2001
Cork........... 5
Cornwall..... 3
York............ 4
Middleton..... 11
Bloomington 6
Normal...... 2
Riverton... 7
Manchac... 1
Colston....... 8
Rooston..... 9
4. Discuss why the mean is considered an unstable measure. What effects do outliers or extreme scores have on the mean that makes it unstable?
Chapter 5
1. What is kurtosis? What do the two types of kurtosis tell researchers about data?
2. Using the data below calculate the Variance.
Grades
89
80
75
65
92
82
90
95
3. Use the same data and calculate the Standard Deviation.
Grades
89
80
75
65
92
82
90
95
4. What do you think the above standard deviation indicates about the data?
