QUANTITATIVE METHODS ASSESSMENT

Quantitative Methods Assessment



Quantitative Methods Assessment

Question 1

Table 1. Summary of the experimental categories used in the study.

Group

code

Species

group

Disruptive

camouflage?

Symmetrical

camouflage?

Sex

Sample

size

1

1

No

No

Male

N = 100

2

1

No

No

Female

N = 100

3

1

Yes

No

Male

N = 100

4

1

Yes

No

Female

N = 100

5

1

No

Yes

Male

N = 100

6

1

No

Yes

Female

N = 100

7

1

Yes

Yes

Male

N = 100

8

1

Yes

Yes

Female

N = 100

9

2

No

No

Male

N = 100

10

2

No

No

Female

N = 100

11

2

Yes

No

Male

N = 100

12

2

Yes

No

Female

N = 100

13

2

No

Yes

Male

N = 100

14

2

No

Yes

Female

N = 100

15

2

Yes

Yes

Male

N = 100

16

2

Yes

Yes

Female

N = 100

On Blackboard, there is an Excel file containing these data. Eight columns of data are present in this file. These eight columns of data are as follows:

COUNTER = a simple case ID code (you will not need to use this in any analysis)

SPECIES = a code for species group (species group 1 = 1, species group 2 = 2)

SYMMETRY = whether the moth had symmetrical camouflage (no = 0, yes = 1)

DISRUPT = whether moth had disruptive camouflage (no = 0, yes = 1)

SEX = sex (male =1, female =2)

TIME = survival time in days. This is the number of days the moth survived during the course of the whole experiment.

SURVIVE49 = whether animal survived to 49 days or not (no = 0, yes = 1). This is a binary variable indicating whether the moth survived to 49 days during the experiment, or whether it was killed before 49 days.

GROUPING = a code detailing the species-sex-symmetry-disruptive grouping. This is the same as the first column in Table 1.

One way analysis of ANOVA

Hypothesis

There is no significant difference in survival time among different groups

There is a significant difference in survival time among different groups

Level of significance = 0.05

Calculation with SPSS

ANOVA

survival time in days

Sum of Squares

df

Mean Square

F

Sig.

Between Groups

71615.325

15

4774.355

48.495

.000

Within Groups

155945.809

1584

98.451

Total

227561.133

1599

From the above table it can be seen that in this case the p value is 0 which is less than level of significance, hence it can be concluded that there is a significant difference in survival time among different groups and null hypothesis should be rejected.

Hypothesis

There is no significant difference in survival time among different species

There is a significant difference in survival time among different species

Level of significance = 0.05

Calculation with SPSS

ANOVA

survival time in days

Sum of Squares

df

Mean Square

F

Sig.

Between Groups

27286.630

1

27286.630

217.721

.006

Within Groups

200274.503

1598

125.328

Total

227561.133

1599

Again in case it can be seen that the p value is less than level of significance and we have to reject our null hypothesis and conclude that there is a significant difference in survival time among different species.

Chi square test

Group * survival time in days (Binned) Crosstabulation

survival time in days (Binned)

Total

<= 8.000000000000

8.000000000001 - 16.593000000000

16.593000000001 - 25.186000000000

25.186000000001 - 33.779000000000

33.779000000001 - 42.372000000000

42.372000000001 - 50.965000000000

50.965000000001 - 59.558000000000

59.558000000001 - 68.151000000000

68.151000000001 - 76.744000000000

76.744000000001+

Group

1

Count

0

0

3

9

7

39

19

19

4

0

100

% within survival time in days (Binned)

.0%

.0%

7.1%

5.0%

2.0%

9.0%

5.1%

11.7%

9.8%

.0%

6.2%

2

Count

0

0

0

1

5

22

39

24

6

3

100

% within survival time in days (Binned)

.0%

.0%

.0%

.6%

1.4%

5.1%

10.5%

14.7%

14.6%

25.0%

6.2%

3

Count

0

0

0

2

4

16

45

25

4

4

100

% within survival time in days (Binned)

.0%

.0%

.0%

1.1%

1.1%

3.7%

12.2%

15.3%

9.8%

33.3%

6.2%

4

Count

0

0

0

0

6

10

34

29

16

5

100

% within survival time in days (Binned)

.0%

.0%

.0%

.0%

1.7%

2.3%

9.2%

17.8%

39.0%

41.7%

6.2%

5

Count

0

0

2

16

33

30

17

2

0

0

100

% within survival time in days (Binned)

.0%

.0%

4.8%

8.8%

9.3%

6.9%

4.6%

1.2%

.0%

.0%

6.2%

6

Count

0

1

2

14

24

34

18

6

1

0

100

% within survival time in days (Binned)

.0%

20.0%

4.8%

7.7%

6.8%

7.9%

4.9%

3.7%

2.4%

.0%

6.2%

7

Count

0

0

1

7

24

27

32

8

1

0

100

% within survival time in days (Binned)

.0%

.0%

2.4%

3.9%

6.8%

6.2%

8.6%

4.9%

2.4%

.0%

6.2%

8

Count

0

0

0

4

16

37

30

9

4

0

100

% within survival time in days (Binned)

.0%

.0%

.0%

2.2%

4.5%

8.6%

8.1%

5.5%

9.8%

.0%

6.2%

9

Count

0

1

4

14

30

28

19

4

0

0

100

% within survival time in days (Binned)

.0%

20.0%

9.5%

7.7%

8.5%

6.5%

5.1%

2.5%

.0%

.0%

6.2%

10

Count

0

0

3

5

24

40

17

8

3

0

100

% within survival time in days (Binned)

.0%

.0%

7.1%

2.8%

6.8%

9.3%

4.6%

4.9%

7.3%

.0%

6.2%

11

Count

0

0

2

9

23

38

20

8

0

0

100

% within survival time in days (Binned)

.0%

.0%

4.8%

5.0%

6.5%

8.8%

5.4%

4.9%

.0%

.0%

6.2%

12

Count

0

0

2

4

15

31

34

12

2

0

100

% within survival time in days (Binned)

.0%

.0%

4.8%

2.2%

4.2%

7.2%

9.2%

7.4%

4.9%

.0%

6.2%

13

Count

1

3

6

36

37

14

3

0

0

0

100

% within survival time in days (Binned)

100.0%

60.0%

14.3%

19.9%

10.5%

3.2%

.8%

.0%

.0%

.0%

6.2%

14

Count

0

0

6

21

36

21

13

3

0

0

100

% within survival time in days ...