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section 2.1.notebook
Using the following "interpretations", determine what statistical measure is being described.
1.The typical phosphate level is an average of 0.6419 mg/dl different from the mean level.
2. The middle 50% of the data lies between 14 and 25 lbs.
3. If all the tips were evenly distributed among the waitresses, each would receive $55.
September 15, 2015
2.1 Describing Location in a Distribution
Use the following scores of 25 students
79 81 80 77 73 83 74 93 78 80 75 67 73 77 83 86 90 79 85 83 89 84 82 77 72
Make a stem plot and calculate the sx and x and interpret each!
4. 50% of the houses cost more than $145,000 and 50% of the houses cost less than $145,000.
Sep 16­1:01 PM
Sep 14­8:33 AM
Sep 12­9:17 AM
Sep 11­10:34 AM
Percentile: The pth percentile of a distribution is the value with p percent of the observations less than it.
Use the scores in the previous problem to find the percentiles for the following students:
a. Norman, who earned a 72
b. Katie, who scored 93
c. The two students who earned scores of 80.
Estimate the Q1 and Q3 for the graph.
Sep 14­8:37 AM
Sep 14­2:40 PM
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section 2.1.notebook
September 15, 2015
Sep 14­4:03 PM
Warm up
If Johnny is in the 55th percentile for his height and 60th percentile for his weight, interpret what that statement means?
Sep 14­4:03 PM
Z­score­ standardized value
Sep 15­7:52 AM
a) Katie scored 93
Sep 17­8:48 AM
The figure below shows a dotplot of the class's height distribution, along with summary statistics from a computer output.
b) Norman scored 72
1. Lynette, a student in the class, is 65 inches tall. Find and interpret her z­score.
2. Another student in the class, Brent, is 74 inches tall. How tall is Brent compared with the rest of the class? Give numerical evidence to support your answer.
3. Brent is a member of the school's basketball team. The mean height of the players on the team is 76 inches. Brent's height translates to a z­score of ­0.85 in the team's height distribution. What is the standard deviation of the team member's heights?
Sep 17­8:50 AM
Sep 17­9:04 AM
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section 2.1.notebook
September 15, 2015
Effects of adding (or subtracting) a constant
Adding the same number "a" to all values in a list results in:
a. adding "a" to measures of center and location
b. does not change the shape or spread.
Sep 17­2:23 PM
Sep 17­8:58 AM
Effects of multiplying (or dividing) a constant
Multiplying the same number "b" to all values in a list results in:
a. multiplies "b" to measures of center and location
b. multiplies the spread.
c. does not change the shape.
Sep 17­9:00 AM
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