SE XXXXXXXXXX
To illustrate a sampling distribution of sample proportions you will do a dice rolling exercise.
1. Roll the die twenty (20) times and record each of your rolls.
2. Circle the even numbers you rolled and count them. Record this value for x1.
3. Divide this number by twenty to determine the proportion of even rolls in your sample of twenty.
Record this proportion as p̂1.
4. Repeat the entire exercise to get a second sample proportion of even rolls.
XXXXXXXXXXX = ______________________________________________________________
XXXXXXXXXXY = ______________________________________________________________
Sample 1 Sample 2
XXXXXXXXXXx1 = _________ XXXXXXXXXXx2 = ______
XXXXXXXXXXp̂1 = _________ XXXXXXXXXXp̂2 = ______
NAME: _________________________________________________ Worksheet #1
XXXXXXXXXXDue ________________________
1. For each of the following variables, decide whether it is qualitative (L) or quantitative (N).
______ a. number of wheels on a vehicle XXXXXXXXXX______ c. a person’s favorite colo
______ b. county a person lives in XXXXXXXXXX______ d. distance a person drives to work
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2. For each of the following quantitative variables, decide whether it is discrete (D) or continuous (C).
______ a. number of ma
les in a jar XXXXXXXXXX______ c. weight of a baby at birth
______ b. number of hours a phone battery lasts XXXXXXXXXX______ d. number of TV’s in a household
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3. A shipment of 2000 tire pressure gauges a
ives at an automotive company warehouse. Fifty of the
tire gauges are randomly selected from various parts of the shipment and the percent of those that
are defective is determined. If this percentage is greater than 5%, the shipment is sent back.
Which of the following is the population of interest for this example?
a. all tire pressure gauges c. the 2000 tire gauges in the shipment
. the 50 randomly selected tire gauges d. 5% of the tire gauges in the shipment
XXXXXXXXXXWhich of the following is the sample for this example?
a. all tire pressure gauges c. the 2000 tire gauges in the shipment
. the 50 randomly selected tire gauges d. 5% of the tire gauges in the shipment
XXXXXXXXXXIf 4 of the 50 randomly selected tire gauges are found to be defective, what percentage is that? Show work.
a. 4% c. 8%
. 12.5% d. 0.08%
The percentage in the previous question is a _____________ .
a. parameter b. statistic
Would the shipment be returned?
a. Yes, because more than 5% of the 50 tire pressure gauges were defective.
. No, because less than 5% of the 50 tire pressure gauges were defective.
c. Unable to be determined because they didn’t check the whole shipment.
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4. Decide in each of the following cases whether it is an example of an observational study (O)
or an experiment (E).
______ a. Does attending an SAT preparation course improve scores? A comparison is done of
XXXXXXXXXXthe math SAT scores between students who attend a 6 week preparation course and
XXXXXXXXXXthose who do not.
______ b. Is there a significant difference in the SAT scores of students who are right-handed as
opposed to those who are left-handed? A comparison is done of the math SAT scores
between students who are right-handed and those who are left-handed.
5. From the numbered list of South Carolina counties given below, you must select a sample of 6 of them
using the string of random digits shown below. Move across that row two digits at a time (since 46 is a
two-digit number) clearly showing your work. Your answer should include the names and numbers of the
counties selected for your sample, in the order you choose them.
1. A
eville 13. Chesterfield 25. Hampton 36. Newbe
y
2. Aiken 14. Clarendon 26. Ho
y 37. Oconee
3. Allendale 15. Colleton 27. Jasper 38. Orangeburg
4. Anderson 16. Darlington 28. Kershaw 39. Pickens
5. Bamberg 17. Dillon 29. Lancaster 40. Richland
6. Barnwell 18. Dorchester 30. Laurens 41. Saluda
7. Beaufort 19. Edgefield 31. Lee 42. Spartanburg
8. Berkeley 20. Fairfield 32. Lexington 43. Sumte
9. Calhoun 21. Florence 33. McCormick 44. Union
10. Charleston 22. Georgetown 34. Marion 45. Williamsburg
11. Cherokee 23. Greenville 35. Marlboro 46. York
12. Chester 24. Greenwood
XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
XXXXXXXXXXno XXXXXXXXXXname
1. _____ ____________________________________
2. _____ ____________________________________
3. _____ ____________________________________
4. _____ ____________________________________
5. _____ ____________________________________
6. _____ ____________________________________
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6. IN AN EXPERIMENT, THERE ARE FOUR CHARACTERISTICS THAT SHOULD BE PRESENT.
EACH IS LISTED BELOW. MATCH THEM WITH THEIR DEFINITIONS.
a. control b. randomization c. replication d. double-blindness
______ How are the subjects assigned to their treatment groups? This assignment must be truly random,
something akin to drawing names out of a hat.
______ There must be a group with whom the experimenter can compare the group that is receiving the
XXXXXXXXXXtreatment of interest. This comparison group usually receives the ‘old, tried-and-true’ treatment
or receives no treatment at all in the form of a placebo.
______ In an experiment with human subjects, neither the subjects nor the experimenter should know
XXXXXXXXXXwho receives what treatment until the end of the experiment. This usually requires the use of
XXXXXXXXXXan impartial third party.
______ If the experiment were repeated under similar conditions, would the results be similar?
XXXXXXXXXXThis is ensured by either repeating the experiment to compare the results or by using a
XXXXXXXXXXlarge sample the first time in order to get reliable results.
7. Below are the recorded speeds of cars on a road with a 50 mph speed