kayla krasley

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