A Beverage Distributor Wanted to Determine the Combination of Advertising $\quad$

question 31

Essay

A beverage distributor wanted to determine the combination of advertising agency (two levels) and advertising medium (three levels) that would produce the largest increase in sales per advertising dollar. Each of the advertising agencies prepared ads as required for each of the media-- newspaper, radio, and television. Twelve small towns of roughly the same size were selected for the experiment, and two each were randomly assigned to receive an advertisement prepared and transmitted by each of the six agency-medium combinations. The dollar increases in sales per advertising dollar, based on a 1-month sales period, are shown in the table. $\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\text { Advertising Medium }$
$\begin{array}{l}\begin{array}{l|c|c|c} & \text { Newspaper } & \text { Radio } & \text { Television } \\\hline \text { Agency 1 } & 15.3,12.7 & 17.4,20.1 & 12.7,16.2 \\\text { Agency 2 } & 22.4,18.9 & 24.3,28.8 & 12.5,9.4\end{array}\end{array}$

$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$${ }^{* *}$ ANALYSIS OF VARIANCE**
SALES
BY AGENCY
MEDIUM


$\begin{array}{lrrrrr}\text { Source of Variation } & \begin{array}{r}\text { Sum of } \\\text { Squares }\end{array} & \text { DF } & \begin{array}{l}\text { Mean } \\\text { Square }\end{array} & \text { F } & \begin{array}{r}\text { Signif } \\\text { of F }\end{array} \\\\{\text { Main Effects }} & 238.299 & 3 & 79.433 & 13.934 & .004 \\\text { AGENCY } & 39.967 & 1 & 39.967 & 7.011 & .038 \\\text { MEDIUM } & 198.332 & 2 & 99.166 & 17.395 & .003 \\\\\text { AGENCY"MEDIUM } & 77.345 & 2 & 38.672 & 6.784 & .029 \\\\\text { Explained } & 315.644 & 5 & 63.129 & 11.074 & .005 \\\text { Residual } & 34.205 & 6 & 5.701 & & \\\text { Total } & 349.849 & 11 & 31.804 & &\end{array}$
(Note: SPSS uses "Explained" instead of "Treatment" in the factorial analysis. Also, SPSS uses "Residual" instead of "Error.") Would you test the main effects factors, agency and medium, in this example? Explain why or why not.

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Definitions:

Glia

Non-neuronal cells in the central nervous system that support, protect, and nourish neurons.

Sodium Ions

Positively charged atomic particles of sodium, essential in the body for maintaining blood pressure and fluid balance, and facilitating nerve and muscle functions.

Axon

A neuron, or nerve cell, features a long, slender outgrowth which is primarily involved in sending electrical messages away from the neuron's main body.

Action Potential

A temporary reversal of electrical polarization of the membrane of a nerve cell or muscle cell, allowing for the transmission of signals.