Researchers investigated the effects of acute stress on emotional picture processing and recall by randomly assigning 40 adult males to receive either a stressful cold stimulus or a neutral warm stimulus before viewing pictures. The researchers computed the relative brainwave amplitude (in microvolts, μV) for each subject viewing unpleasant versus neutral pictures. They also recorded how many pictures the subjects were able to recall 24 hours later. The following model is proposed for predicting the brainwave relative amplitude ("amplitude") from the number of images recalled ("recall"), the indicator variable reflecting the nature of the stimulus ("stress"), and an interaction term ("recall*stress"): Amplitude_i = β₀ + β₁ (recall_i) + β₂ (stress_i) + β₃ (recall*stress_i) + ε_i Where the deviations ε_i are assumed to be independent and Normally distributed with mean 0 and standard deviation σ. This model was fit to the sample of 40 adult males. Using software, we obtained the following output: $\begin{array}{lrr} \text { Predictor } & \text { Coef } & \text { SE Coef } \ \text { Constant } & 4.795 & 1.329 \ \text { recall } & -0.1139 & 0.1069 \ \text { stress } & -4.262 & 2.205 \ \text { recall* stress } & 0.4337 & 0.1677 \end{array}$

Predicted Values for New Observations

New Obs Fit SEFit 95%CI 95%

PI

1 3.731 0.624 (2.465,4.996)

2 3.656 0.508 (2.625,4.686)

Values of Predictors for New Observations New

New Obs recall stress recall*stress

1 10.0 1.00 10.00

2 10.0 0.00 0.00

Which of the following statements best describes the interval (2.465, 4.996)?

Question

Researchers investigated the effects of acute stress on emotional picture processing and recall by randomly assigning 40 adult males to receive either a stressful cold stimulus or a neutral warm stimulus before viewing pictures. The researchers computed the relative brainwave amplitude (in microvolts, μV) for each subject viewing unpleasant versus neutral pictures. They also recorded how many pictures the subjects were able to recall 24 hours later. The following model is proposed for predicting the brainwave relative amplitude ("amplitude") from the number of images recalled ("recall") , the indicator variable reflecting the nature of the stimulus ("stress") , and an interaction term ("recall*stress") :
Amplitude_i = β₀ + β₁ (recall_i) + β₂ (stress_i) + β₃ (recall*stress_i) + ε_i
Where the deviations ε_i are assumed to be independent and Normally distributed with mean 0 and standard deviation σ. This model was fit to the sample of 40 adult males. Using software, we obtained the following output:

\begin{array}{lrr}\text { Predictor } & \text { Coef } & \text { SE Coef } \\\text { Constant } & 4.795 & 1.329 \\\text { recall } & -0.1139 & 0.1069 \\\text { stress } & -4.262 & 2.205 \\\text { recall* stress } & 0.4337 & 0.1677\end{array}

Predicted Values for New Observations
New					Obs	Fit	SEFit	95%CI	95%
PI
	1	3.731	0.624	(2.465,4.996)
	2	3.656	0.508	(2.625,4.686)

Values of Predictors for New Observations New
New					Obs	recall	stress	recall*stress
	1	10.0	1.00	10.00
	2	10.0	0.00	0.00

Which of the following statements best describes the interval (2.465, 4.996)?

Quizplus · Accepted Answer

The interval (2.465, 4.996) is a confidence interval for the mean brainwave relative amplitude for all adult men exposed to a stressful stimulus who recall 10 pictures, as indicated by the stress value of 1.00 in the predictors table.

Researchers Investigated the Effects of Acute Stress on Emotional Picture