When two targets are presented close together in a rapid visual stream, the second target is often missed. Psychologists call this phenomenon the attentional blink (AB). A study published in Advances in Cognitive Psychology (July 2013) investigated whether simultaneous or preceding sounds could reduce AB. Twenty subjects were presented a rapid visual stream of symbols and letters on a computer screen and asked to identify the first and second letters (the targets). After several trials, the subject's AB magnitude was measured as the difference between the percentages of first target and second target letters correctly identified. Each subject performed the task under each of three conditions. In the Simultaneous condition, a sound (tone) was presented simultaneously with the second target; in the Alert condition, a sound was presented prior to the coming of the second target; and in the No-Tone condition, no sound was presented with the second target. Scatterplots of AB magnitude for each possible pair of conditions are shown below as well as the least squares line for each.

a. Which pair of conditions produces the least squares line with the steepest estimated slope?

b. Which pair of conditions produces the least squares line with the largest SSE?

c. Which pair of conditions produces the least squares line with the smallest estimate of \(\sigma\)?

Make a scatterplot of the data. Use 87 for 1987

.\(\begin{array}{|c|c|} \hline \text{ Year } & \text{ Sales (millions of dollars)} \\ \hline 1987 & 300 \\ \hline 1988 & 345 \\ \hline 1989 & 397 \\ \hline 1990 & 457\\ \hline 1991 & 510 \\ \hline 1992 & 578 \\ \hline 1993 & 664 \\ \hline 1994 & 700 \\ \hline 1995 & 770 \\ \hline 1996 & 792 \\ \hline 1997 & 830 \\ \hline 1998 & 872 \\ \hline 1999 & 915 \\ \hline \end{array}\)

Some high school physics students dropped a ball and measured the distance fallen (in centimeters) at various times (in seconds) after its release. If you have studied physics, you probably know that the theoretical relationship between the variables is distance \(=490(time)^2.\) Which of the following scatter-plots would not approximately follow a straight line?

(a) A plot of distance versus \(time^2\)

(b) A plot of radic distance versus time

(c) A plot of distance versus radic time

(d) A plot of \(\ln\)(distance) versus \(\ln(time)\)

(e) A plot of \(\log\)(distance) versus \(\log(time)\)