Question

The number of newly reported crime cases in a county in New York State is shown in

Answer 1

Answer:

The linear regression equation that represents  the set of data is:

$y=1083.48+23.73x$

The predicted number of new cases for 2013 is 1368.

Step-by-step explanation:

The general form of a linear regression is:

$y=a+bx$

Here,

y = dependent variable

x = independent variable

a = intercept

b = slope

Compute the values of a and b as follows:

$\begin{aligned} a &= \frac{\sum{Y} \cdot \sum{X^2} - \sum{X} \cdot \sum{XY} }{n \cdot \sum{X^2} - \left(\sum{X}\right)^2} = \frac{ 6857 \cdot 55 - 15 \cdot 17558}{ 6 \cdot 55 - 15^2} \approx 1083.476 \\ \\b &= \frac{ n \cdot \sum{XY} - \sum{X} \cdot \sum{Y}}{n \cdot \sum{X^2} - \left(\sum{X}\right)^2} = \frac{ 6 \cdot 17558 - 15 \cdot 6857 }{ 6 \cdot 55 - \left( 15 \right)^2} \approx 23.743\end{aligned}$

The linear regression equation that represents  the set of data is:

$y=1083.48+23.73x$

Compute the predicted value of the number of new cases for 2013 (i.e. x = 12) as follows:

$y=1083.48+23.73x$

  $=1083.48+(23.73\times12)\\\\=1083.48+284.76\\\\=1368.24\\\\\approx 1368$

Thus, the predicted number of new cases for 2013 is 1368.