Researchers measured the occurrence of reptiles using pitfall trapping across mallee Eucalyptus habitats that had been either recently burnt or unburnt. They were interested in comparing the abundance Southern knob-tail geckos (Nephrurus stellatus) between these two habitats and so calculated the relative abundance of this species found at each trap. Based on the output below, what would be the most correct conclusion to draw about these data?
Mean
n
Std deviation
Std error of mean
burnt sites
8.08
30
6.12
0.94
unburnt sites
2.73
30
3.33
0.51
Variance ratio test = 3.37 : 1
options:
The data are skewed and a log transformation (after adding 10 too all values to remove negative and zero values) should be attempted before performing a parametric test
The data are skewed, however a transformation would not be appropriate for these data
The data are symmetrical, a parametric test would be suitable for these data
The data are skewed and an arcsine transformation should be attempted before performing a parametric test
Transcribed Image Text:burnt
unburnt
-5
O
0
5
Relative abundance
10
O
15
20
25
Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
