Transcript Statistics for Research in Ecology

Sabrina Alexis
Average Lenght of Sharp-Nosed Sharks
1010
1000
990
Lenght (cm)
980
970
960
950
940
930
920
Male
Female
Gender of Shark
Survival of the Sea Turtles
Amount of Sea Turtles
25
20
15
Survived
10
Started Out
5
0
Started Out
Blue
Yellow
Green
Colors
Survived
Red
Orange
Percentage of Bottle Cap Colors
5%
27%
10%
1% 0%
Red
Orange
14%
Yellow
Blue
4%
Green
8%
Purple
0%
31%
Black
White
Clear
Other
14
Frequency of Sea Cigars
12
Frequency
10
8
6
4
2
0
"1-5"
"6-10"
"11-15
"16-20"
Size Intervals (cm)
"21-25"
"26-30"
Probability is a way to measure the chances that
something will occur in relation to the possible
alternatives.
There are many reasons why corals are dying. For
example:
 Coral bleaching, which is caused by elevated sea
surface temperatures due to global climate change
 Rising levels of CO2
 Over fishing (bomb and cyanide fishing)
Coral reefs need the water to be between 74-84
degrees Fahrenheit. If the temperature is even 1
degree more or 1 degree less the coral reefs will die.
The temperatures are going up because of global
warming. Coral bleaching is when the water is too
warm, corals will force out the algae
(zooxanthellae) living in their tissues causing the
coral to turn completely white. This is called coral
bleaching.
Variance is used in statistics to describe
how far away your data is from the
mean.
This is the formula for variance:
A Theoretical Distribution Curve (TDC) is a theoretical
or ideal picture of a distribution based upon random
sampling.
Theoretical Distributions of 25 Sea Cigar lenghts
Example:
3
2.5
Frequency
2
1.5
1
0.5
0
0
5
10 of Sea Cigars (in
15 cm)
Lenght
20
25
This is the formula pool variance:
A T-test is an equation used to
determine whether there’s a
significant difference
between two group means.
The t-statistic is designed to
test if the is a major
difference between the
means of the independent
samples.
This is a T-test:
A chi square test is used to see if there
are any significant differences
between data sites and sources.
Today in statistics we played a
turtle game to se if there was a
difference in the survival rates
of turtles at different beach
sites.
Sea turtles have many
predators such as:
 Raccoons
 Crabs
 Humans
 And birds
Sea turtles are also injured by
marine debris. If they eat plastic
bags (which somewhat look like a
jellyfish) then it will stay in there
stomachs and they are not able to
digest it. Soon they will die because
it is stored in their stomachs for a
long time.
This data shows that there
is no difference between
the treatment and control
group.
C1
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T1
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C2
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T2
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C3
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T3
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C4
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T4
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DIED
C5
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T5
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C6
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T6
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C7
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T7
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C8
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T8
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C9
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T9
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C10
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T10
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C11
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T11
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C12
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T12
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C13
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T13
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C14
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T14
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C15
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T15
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