lab 2

Question 1

how to know if sample representative of population

Answer 1

unbiased and adequate in size

Question 2

random sampling

Answer 2

sampling randomly using random number generators etc

Question 3

systemic sampling

Answer 3

taking samples that have regular arrangement

Question 4

advantages to systemic sampling

Answer 4

easyer

Question 5

combination sampling

Answer 5

combination of systemic and random sampling

Question 6

which sampling method is recommended

Answer 6

random sampling- stat tests based off this

Question 7

is it better to take more small samples or less large samples?

Answer 7

more small samples

Question 8

a homogenous area will require

Answer 8

less sampling than a heterogeneous one

Question 9

highly clumped populations may require

Answer 9

more samples than random or uniform pop

Question 10

performance curve

Answer 10

plots cumulative mean value of a trait against number of samples taken

Question 11

how is cumulative mean calcualted

Answer 11

summing the total number of objects encountered and dividing it by total asamples

Question 12

Quadrat method uses

Answer 12

used for estimating absolute pop density
-used for small sessile or relatively sedentary organisms

Question 13

mark/ recapture uses

Answer 13

estimating absolute population density
-used for large and or mobile organisms

Question 14

quadrat process

Answer 14

square shaped sampling area of known/ defined size, count all individuals and extrapolate to entire area

Question 15

Quadrat variables
n
alpha
A
N
N(hat)

Answer 15

n= average number sampled in quadrats
alpha= size of quadrat
A= total area
N=total pop size
N hat=estimated total pop size

Question 16

N(hat) when do you round

Answer 16

when there is a decimal, always round

Question 17

Mark recapture process

Answer 17

capture sample of individuals, mark, release into pop allow to disperse
recapture random sample, note # of marked and unmarked

Question 18

Assumption of mark recapture

Answer 18

marks must not be lost or overlooked
no change in ration of marked to unmarked animals as a result of birth, death, immigration or emigration
-marked and unmarked similar in all aspects- trappability etc
-probability for recapture equal for marked and unmarked

Question 19

Mark recapture variables
M
m
N
n

Answer 19

M=total number marked in population
m=number marked in sample
N=total population size
n=total number in the sample