91影视

The phenotype codes of pea are listed as follows:

• smooth-yellow is coded as 1
• smooth-green is coded as 2
• wrinkled-yellow is coded as 3
• wrinkled-green is coded as 4

(a)

The formula for the mean is:

$\stackrel{炉}{x}=\frac{鈭�x}{n}$where, xrepresents the values and n is the sample size.

Substitute the values in the formula.

role="math" localid="1643799208055" $$\begin{gathered} \stackrel{炉}{x}=\frac{2+1+...+2}{25} \\ =\frac{47}{25} \\ =1.88 \end{gathered}$$

Thus, the mean value is 1.9.

(b)

The formula for the median is stated as follows:

• The middlemost observation is equal to the median if n is odd.
• The average of the two middlemost observations is equal to the median if n is even.

The sample size is 25.

Arrange the observations in ascending order.

The middlemost observation is 2.

The median is given as:

$M=2$

Thus, the median is 2.0.

(c)

Mode is/are the observation(s) in the data with the highest repetitions.

The frequency distributions for the phenotypes are:

The highest frequency is obtained for phenotype 1.

Thus, the mode of the data is 1.

(d)

The formula for midrange is stated as:

Substitute the values in the formula.

$$\begin{gathered} \text{Midrange}=\frac{1+4}{2} \\ =\frac{5}{2} \\ =2.5 \end{gathered}$$

Thus, the midrange is 2.5.

The data is recorded for four types of phenotypes. The phenotypes are categorical, which cannot be ordered. Thus, the data is nominal scaled data.

The measures of the center can be computed for the numerically expressed categories as shown above.

However, the measures for the center, except mode, are meaningless for nominal data and do not make any sense.