The authors of a paper describe an experiment to evaluate the effect of using a cell phone on reaction time. Subjects were asked to perform a simulated driving task while talking on a cell phone. While performing this task, occasional red and green lights flashed on the computer screen. If a green light flashed, subjects were to continue driving, but if a red light flashed, subjects were to brake as quickly as possible. The reaction time (in msec) was recorded. The following summary statistics are based on a graph that appeared in the paper. n = 49       x = 525       s = 65 Suppose that the researchers wanted to estimate the mean reaction time to within 5 msec with 95% confidence. Using the sample standard deviation from the study described as a preliminary estimate of the standard deviation of reaction times, compute the required sample size. (Round your answer up to the nearest whole number.) n =

Tim is interested in studying whether Cognitive Behavioural Therapy (CBT) is an effective treatment for Obsessive Compulsive Disorder (OCD). Six people who were diagnosed with OCD participated in Tim's study, where he recorded the number of times they washed their hands per day for one month. They were then given a three week intensive CBT program before their hand-washing was monitored for another month. The average number of times per day each participant washed their hands over the two months of observation are as follows: Participant Month 1 Month 2 1 11 6 2 8 5 3 14 17 4 10 10 5 22 11 6 15 10   Compute the appropriate statistic to determine whether the program was effective and use this information to fill in the blanks:   Q1. revealed that the number of times per day participants washed their hands following the CBT program was Q2. compared to the number of times per day participants washed their hands before the…

Suppose two variables are negatively correlated. Does the response variable increase or decrease as the explanatory variable increases?

A researcher gathered a sample of participants who volunteered for a studying of phobias. She measured anxiety level of participants as they viewed photos of spiders and again when they viewed puppies. Which statistical test is appropriate for this study and why?

Suppose that, as part of a research methods class, Bailey was asked to write a summary of a research paper on the topic of the effects of visitor traffic on the relative humidity in bat caves.                        Identify the explanatory and the response variables.                                                                                                                                                                                                                                                         The number of visitors and the relative humidity are the response variables. The number of visitors is the response variable, and the relative humidity is the explanatory variable. The number of visitors and the relative humidity are the explanatory variables. The number of visitors is the explanatory variable, and the relative humidity is the response variable.

Auditors must make judgments about various aspects of an audit on the basis of their own direct experience, indirect experience, or a combination of the two. In a study, auditors were asked to make judgmentS about the frequency of errors to be found in an audit. The judgments by the auditors were then compared to the actual results. Suppose the following data were obtained from a similar study; lower scores indicate better judgments. If answer is zero enter "0". Direct Indirect Combination 18.0 17.8 15.6 17.8 19.2 16.3 14.0 17.0 21.4 20.2 19.1 24.3 19.1 20.3 24.5 24.8 20.9 27.0 26.7 25.0 23.9 Source Sum of Degrees Mean Square F p-value of Squares of (to 2 (to 2 (to 2 Variation (to 2 decimals) Freedom decimals) decimals) decimals) Treatments Error Total Use a = 0.05 to test to see whether the basis for the judgment affects the quality of the judgment. The p-value is - Select your answer - What is your conclusion? Select your answer -

A psychologist conducted a survey of the attitude towards the sustainability of American energy consumption with 250250 randomly selected individuals several years ago. The psychologist believes that these attitudes have changed over time. To test this he randomly selects 250250 individuals and asks them the same questions. Can the psychologist confirm his theory that the attitudes have changed from the first survey to the second survey? Attitude 1st Survey 2nd Survey Optimistic 50%50% 52%52% Slightly Optimistic 16%16% 10%10% Slightly Pessimistic 11%11% 15%15% Pessimistic 23%23% 23%23% Copy Data Step 6 of 10 :   Find the value of the test statistic. Round your answer to three decimal places. Step 7 of 10: Find the degrees of freedom associated with the test statistic for this problem Step 8 of 10: Find the critical value of the test at the 0.025 level of significance. Round your answer to three decimal places.step 9 of 10: make the decision to reject or fail to reject…

Melinda thinks that stress might predict lower grades on a statistics final exam. She gives a sample of statistics students a questionaire and then looks for relationships between their answers and their final exam scores. Although she finds no support for her original hypothesis, she does find that the the numbers of hours that students work outside of school is related to exam performance. When she reports the results of her study, she presents them as if the relationship between number of hours worked and exam performance was her original hypothesis. This is a questionable research practice known as: a. open science b. p-hacking c. HARKing d. constraints of generality