kayla krasleykayla krasley mandy schafermandy schafer
TRANSCRIPT
Kayla Krasley
Mandy Schafer
Created in Detroit, Michigan in 1915
Automobiles outdoing horse and buggies
Early signs were the word “stop” in black on a white piece of metal
Sign to get people to think twice before crossing
Became a more serious sign in the flow of traffic
Yellow octagon with black letters
Later changed to red
Used worldwide except in Japan
Only octagon shaped sign on the highway
Must stop and wait for all the intersection to clear
Determine community safety
Determine gender differences abiding by the traffic laws
Look at age affects
Stop sign into South student parking lot from Bristol Road
Stop sign in front South parking lot by flag pole
Stop sign in front of Giant on Rt. 202
Stop sign in front of Toys ‘R Us on Rt. 309
Divided our data into ½ second intervals
Categorical Time Stopped
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
Categorical Time Stopped
0
20
40
60
80
100
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
Time (s)
Car C
ount
Car Count
Min = 0
Q1 = 0
Median = 0.28
Q3 = 1.14
Max = 4.13
Mean = .70385
Std Dev = .9127
Time Versus Gender
0
10
20
30
40
50
60
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
Time (s)
Co
un
t
Male
Female
AssumptionsSRS
Normal Population or n ≥ 30
Assumed
192 ≥ 30
Hypotheses Ho: μ = 3
Ha: μ < 3
t- Test
t = -34.857
ConclusionWe reject Ho in favor of Ha because p-value of 0 < α = 0.05. We have sufficient evidence that the mean time for stopping is less than 3
seconds.
P(t < -34.857 | df = 191) = 0
95% Confidence Interval
= (.57392, .83379)
ConclusionWe are 95% confident that the mean time for
stopping is between .57392 and .83379 seconds.
*
Assumptions2 independent SRS
Sample size large enough so all
expected counts ≥ 5
Assumed
exp counts ≥ 5
Hypotheses Ho: There is no association between
gender and the time stopped
Ha: There is an association between gender and the time stopped
Time Male Female Totals
0 51 34 85
0.5 12 14 26
1 16 10 26
1.5 9 8 17
2 8 9 17
2.5 7 2 9
3 4 2 6
3.5 3 2 5
4 0 0 0
4.5 0 1 1
5 0 0 0
110 82 192
X² - Test
X² = 5.739
ConclusionWe fail to reject Ho because our p-value
of .6764 > α = 0.05. We have sufficient evidence that there is no association between
gender and the time stopped.
P(X² > 5.739 | df = 8) = .6764
Assumptions2 independent SRS
nm(pm)nm(1-pm)
nf(pf)nf(1-pf)
popm ≥ 10nmpopf ≥ 10nf
Assumed
(.46)(110)(.54)(110)(.41)(82)(.59)(82)
Hypotheses Ho: pm = pf
Ha: pm < pf
≥ 10 ≥ 10
popm ≥ 10(110)popf ≥ 10(82)
z - Test
z = .67619
ConclusionWe fail to reject Ho in favor of Ha because p-value of .2495 > α = 0.05. We have sufficient
evidence that the proportion of males that stop is equal to the proportion of
females that stop.
P(z > .67619) = .2495
95% Confidence Interval
= (-.0926, .19062)
ConclusionWe are 95% confident that the difference in proportion of males and females that don’t
stop at stop signs is between -.0926 and .19062.
< < < < < <
South needs to be more aware of safety
Saving a life is more important
Watch for pedestrians
One should always stay on their side of the road
2007 Statistics
Passenger vehicle deaths: 28,933Injuries: 2,221,000
Pedestrian Deaths: 4,654Injuries: 70,000
Each Year200 fatal and 17,000 nonfatal crashes
due to running stop signs
Be cautious of other drivers
Speed bump at South confuses drivers
Buses block the stop sign at South
Different techniques with stopwatch
Time of day
Type of stop signs
