A variety of experiments suggest that visual images interfere with visual perception. In one study, Segal and Fusella (1970) had participants watch a screen, looking for brief presentations of a small blue arrow. On some trials, the participants were also asked to form a mental image (for example, imagine a volcano). The results for a sample of N = 16 show that participants made an average of 1.8 more errors while forming images than while not forming images. The difference scores had SS = 378. (a) Compute a 95% confidence interval for µ, the population mean difference score. (b) Perform a hypothesis test to decide whether people make significantly more errors on the task when forming visual images

To examine the effect of relaxing music on math test performance, a researcher wants to compare the average math test scores of participants who completed the test with relaxing music to performance of participants who completed the same math test without music. The partially computed data collected in the study are shown below: Math Test with Music:         Math Test without Music: n1 = 16                                     n2 = 12 M1 = 82                                    M2 = 78 SS1 = 150                                 SS2 = 140 Based on these results, is there a significant effect of relaxing music on math test performance? Use a t-test for independent samples with p < .01, 2-tails to answer this research question. Follow the steps of hypothesis testing and insert your answers below. In your calculations, round all numbers to two decimal places to avoid rounding errors. ANSWER H0: H1: Computed pooled variance sp2: Estimated standard SM1 - M2: Computed t: Critical t-value for…

In an early study of the effects of frustration on feelings of hostility, Miller and Bugelski (1948) had a group of boys at a camp rate their attitudes toward two groups (Mexicans and Japanese). The campers then participated in a long, difficult, frustrating testing session that kept them away from their weekly movie. Finally the boys again rated their attitudes towards the minority groups. The scores below represent the number of unfavorable traits attributed to minorities and are similar to those of miller and Bugelski.    Participant   Before          After    A                  5                    6    B                  4                    4    C                  3                    5    D                  3                    4    E                  2                    4    F                  2                     3    G                 1                    3    H                 0                    2   a. Does the intervening unpleasant task alter attitudes toward the two…

. Do patients with gastrointestinal issues experience more psychological distress than the general population?   The DASS-21 questionnaire is a validated measure of depression, anxiety, and stress. For the general population, the mean for anxiety is µ = 4.2. Anxiety levels are calculated based on self-reported answers to questions on a scale from 0 through 42, with lower scores indicating lower anxiety.   Participants with gastrointestinal issues (specifically inflammatory bowel disease, IBD) completed the DASS-21. Use the data presented below to determine whether having gastrointestinal issues like IBD significantly increases risk for anxiety. Test whether or not the performance of this sample is significantly higher than the normal population using the proper t-test.  Here are the data:   Anxiety scores: 12, 15, 10, 8, 10, 5, 10, 13, 4, 6   ANALYSES AND UNGRADED OPTIONAL GUIDING QUESTIONS: 1a. Identify the Indep.Variable:__                  Dep.Variable:__ Is it the Hypothesis…

Is the proportion of wildfires caused by humans in the south higher than the proportion of wildfires caused by humans in the west? 367 of the 526 randomly selected wildfires looked at in the south were caused by humans while 390 of the 594 randomly selected wildfires looked at the west were caused by humans. What can be concluded at the a = 0.01 level of significance? a. For this study, we should use Select an answer b. The null and alternative hypotheses would be: Ho: Select an answer > Select an answer > Select an answer O (please enter a decimal) H j: Select an answer Select an answer > Select an answer O (Please enter a decimal) c. The test statistic (please show = your answer to 3 decimal places.) d. The p-value (Please show your answer to %3D 4 decimal places.)

Consider the following studies. Study I: A researcher randomly divided 200 high school students into two groups. The first group was told to not exercise. The second group was told to exercise at least 5 hours each week. At the end of two months, the heart rates of each participant in each group were measured at rest. It was found that the group that exercised 5 hours a week had a significantly lower average heart rate. Study II: A researcher gathered 200 high school students randomly, asked them how long they exercised each week, and then measured their heart rates at rest. It was found that students who exercised at least 5 hours a week had a significantly lower average heart rate. Part A: Which study was experimental? Why?  Study IStudy II Part B: List the explanatory and response variables in the studies.  Explanatory: heart rate; Response: exercise timeExplanatory: student; Response: amount of exerciseExplanatory: exercise time; Response: heart rate Part C: State whether the…

Weinstein, McDermott, and Roediger (2010) report that students who were given questions to be answered while studying new material had better scores when tested on the material compared to students who were simply given an opportunity to reread the material. In a similar study, an instructor in a large psychology class gave one group of students questions to be answered while studying for the final exam. The overall average for the exam was u = 73.4, but the n = 16 students who answered questions had a mean of M = 78.3 with a standard deviation of s = 8.4. t Distribution Degrees of Freedom = 21 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 AAN For this study, did answering questions while studying produce significantly higher exam scores? Use a two-tailed test with a = .05 and the Distributions tool to help. (Round your answers to three decimal places, when needed.) SM t-critical = The results indicate: Rejection of the null hypothesis; answering questions while studying produces significantly higher…

In the vertical-horizontal line illusion, the two lines are exactly the same length, but the vertical line appears to be much longer. To examine the strength of this illusion, a researcher prepared an example in which both lines were exactly 10 inches long. The example was shown to individual participants who were told that the horizontal line was 10 inches long and then were asked to estimate the length of the vertical line. For a sample of n = 25 participants, the average estimate was M = 12.2 inches with a standard deviation of s = 1.00.  Calculate t statistic.

pls answer D on paper