Psychology_Chapter__Placebo___Hawthorne_Effects.pdf

Psychology Chapter: Placebo & Hawthorne Effects Your Name: 1. What is the primary purpose of the technique called blinding in experiments? A. To increase the sample size B. To simplify data analysis C. To enhance participant motivation D. To prevent bias from affecting results 2. Whic...

Psychology Chapter: Placebo & Hawthorne Effects Your Name: 1. What is the primary purpose of the technique called blinding in experiments? A. To increase the sample size B. To simplify data analysis C. To enhance participant motivation D. To prevent bias from affecting results 2. Which of the following describes the Hawthorne effect? A. Participants ignore instructions from researchers B. Participants behave differently because they know they are being observed C. Participants show improved performance due to experimental manipulation D. Participants react negatively to experimental conditions 3. In a double-blind experiment, who remains unaware of group assignments? A. Both the participants and the researchers B. Only the external observers C. Only the researchers D. Only the participants 4. What type of graph uses lines to connect frequencies at the midpoints of classes? A. Ogive B. Histogram C. Bar graph D. Frequency polygon 5. Which graph visually represents cumulative frequencies for classes? A. Pie chart B. Histogram C. Bar graph D. Ogive 6. What is the primary advantage of using blinding in research studies? A. It ensures participant compliance B. It reduces the placebo effect and bias C. It allows researchers to predict outcomes D. It eliminates ethical concerns 7. How does a histogram represent its data? A. Using segmented pie slices B. With continuous vertical bars of various heights C. By plotting individual data points scattered on a graph D. Through horizontal lines connecting points 8. Why might participants change their behavior during a study related to the Hawthorne effect? A. Because they know they are being observed B. Due to the effects of the environment C. Because they were instructed to do so D. Due to the presence of medication 9. What is the quadratic mean (QM) calculated from? A. The average of the original values. B. The sum of the original values divided by the number of values. C. The square root of the average of the squares of each value. D. The average of the deviations of each value from the mean. 10. Which method is used to find an approximate median for grouped data? A. Find the maximum and minimum values of the data. B. Count the total number of observations. C. Calculate the mean of the dataset. D. Identify the median class and assume even distribution within. 11. In statistical analysis, what does a large variance indicate? A. The data values are all identical. B. The data values are closely packed together. C. The data has a normal distribution. D. The data values are more dispersed. 12. What does Chebyshev’s theorem guarantee about data values in a distribution? A. All data values will be within 1 standard deviation of the mean. B. At least 75% of data will be within 2 standard deviations of the mean. C. The mean and median will always be equal. D. No data values will lie outside 3 standard deviations. 13. According to the empirical rule for normal distributions, what proportion of data values falls within 2 standard deviations of the mean? A. Approximately 75% B. Approximately 68% C. Approximately 50% D. Approximately 95% 14. How is the consistency of a variable assessed using variance and standard deviation? A. By examining the dispersion of the data values. B. By comparing the range of the data values. C. By counting the number of observations in the data set. D. By measuring the central tendency of the data. 15. Which of the following applications does not involve variance and standard deviation? A. Comparing two data sets for variability. B. Finding the median of a data set. C. Determining the number of data values within an interval. D. Assessing the spread of data. 16. What aspect of a distribution is Chebyshev’s theorem applicable to? A. Only bell-shaped distributions. B. Only skewed distributions. C. Any distribution, regardless of shape. D. Only uniform distributions. 17. What does the notation P(B|A) represent? A. The probability that event A occurs given event B. B. The probability that event B is divided by event A. C. The probability that event B occurs after event A. D. The probability that event A and event B occur independently. 18. What is a key difference between permutations and combinations? A. Permutations consider the order of objects while combinations do not. B. Permutations are arrangements in pairs while combinations are not. C. Combinations are always greater than permutations. D. Permutations can only involve distinct objects. 19. How is the total number of circular permutations affected when clockwise and anti-clockwise orders are treated as different? A. It is calculated as Pn = (n!) / 2. B. It is calculated as Pn = 2(n-1)!. C. It is calculated as Pn = (n-1)!. D. It remains the same as linear permutations. 20. Which of the following defines a discrete variable? A. A variable that cannot be enumerated. B. A variable that has an infinite number of non-countable outcomes. C. A variable that can take on any value within a given range. D. A variable whose values are determined by chance and can be counted. 21. What does the concept of expected value represent? A. It provides a weighted average of all outcome values based on their probabilities. B. It signifies the median of a probability distribution. C. It predicts the most frequent outcome in an experiment. D. It indicates the sum of all possible outcomes. 22. What is the primary characteristic of a discrete probability distribution? A. It represents probabilities that cannot be determined accurately. B. It includes values a random variable can assume with their corresponding probabilities. C. It consists of continuous ranges of values. D. It belongs only to binary outcomes. 23. In which scenario would you use the binomial distribution? A. When there are two outcomes, such as heads or tails from a coin toss. B. When a process can result in more than two variables. C. When the outcomes are dependent on each other. D. When there are multiple outcomes with equal probabilities. 24. How can the fundamental counting rule be applied? A. To determine the total number of outcomes in a probability problem without restrictions. B. To express combinations in factorial notation. C. To accurately compute the probability of two or more dependent events. D. To calculate probabilities only when events occur independently. 25. What does the total area under a normal distribution curve equal? A. 2.00 or 200% B. 1.50 or 150% C. 1.00 or 100% D. 0.50 or 50% 26. How much area under a normal curve lies within 2 standard deviations of the mean? A. 0.68 or 68% B. 0.75 or 75% C. 0.99 or 99% D. 0.95 or 95% 27. What is the mean of the distribution of sample means compared to the population mean? A. Always higher than the population mean B. Always lower than the population mean C. The same as the population mean D. Unrelated to the population mean 28. What does the standard deviation of the sample means depend on? A. Both population standard deviation and sample size B. Square root of the sample size C. Sample population size D. Population standard deviation only 29. What is a sampling distribution of sample means? A. A distribution of individual data points B. A distribution of population measures C. A random assortment of sample values D. A distribution using the means of multiple samples 30. How does the curve of a normal distribution relate to the x-axis? A. It only touches the x-axis at the mean B. It never touches the x-axis C. It intersects the x-axis at one point D. It touches the x-axis at two points 31. What happens to the sample means as more random samples are taken? A. They always increase B. They vary randomly without a concept C. They form a sampling distribution D. They become constant 32. What is the relationship between the sample size and sampling error? A. Sampling error remains constant regardless of sample size B. Sampling error increases with larger sample sizes C. Sampling error has no relation to sample size D. Sampling error decreases with larger sample sizes 33. What is the best point estimate of the population mean μ? A. The mode of the sample B. The population mean itself C. The median of the sample D. The sample mean X̅ 34. What determines the confidence level of an interval estimate? A. The range of values selected from the sample B. The sample size alone C. The probability that the interval contains the parameter D. The choice of population parameters 35. When can the z distribution be used to find the confidence interval for the mean? A. When the sample size is less than 30 B. When the population is not normally distributed regardless of sample size C. When the sample size is 30 or more if s is known D. When the sample mean is less than the population mean 36. What is the margin of error in an interval estimate? A. The difference between the sample mean and population mean B. The maximum likely difference between the point estimate and actual parameter value C. The range of values in the sample D. The average of all sample values 37. What sample size is needed for the central limit theorem to apply when the original variable is not normally distributed? A. 20 or more B. 10 or more C. 15 or more D. 30 or more 38. Which statement about confidence intervals is true? A. They provide a range of values for a single observation B. They are determined using a specific confidence level and sample data C. They depend solely on the sample median D. They always include the population parameter 39. If the sample mean X̅ is 22.3 years, what type of estimate is this? A. Population estimate B. Interval estimate C. Range estimate D. Point estimate 40. Which of the following factors does NOT influence the approximation of the distribution of the sample means? A. Sample size B. Total number of observations in the population C. Variability in data measurements D. Shape of the original variable's distribution