IIBA® – CBDA Exam Free Cloned Questions 3 1234567891011121314151617181920 Created by aboozarkordi IIBA® – CBDA Exam Free Cloned Questions 1 / 20 1. What is an assumption for a chi-squared test of independence? A) Independence of observations B) Random sampling C) Normal distribution of the data D) Homogeneity of variances An assumption for a chi-squared test of independence is that the observations are independent of each other. 2 / 20 2. For a normal distribution with a mean of 70 and a standard deviation of 5, what is the probability that a randomly selected value is greater than 75? A) 50.00% B) 34.13% C) 15.87% D) 15.87% Using z-scores, we find that the probability of a value greater than 75 is approximately 15.87%. 3 / 20 3. A company wants to estimate the average satisfaction score of its customers. Which sampling method is most appropriate for obtaining a representative sample from its customer database? A) Stratified Sampling B) Convenience Sampling C) Quota Sampling D) Simple Random Sampling Simple Random Sampling would be most appropriate as it ensures every customer has an equal chance of being selected, providing a representative sample from the entire customer base. 4 / 20 4. A claim has been made that the risk of companies admitted to the stock exchange is less than 1000. What are the hypotheses for the test? A) H0 :μ≤1000,H1 :μ>1000 B) H0 :μ>1000,H1 :μ≤1000 C) H0 :μ=1000,H1 :μ≠1000 D) H0 :μ≥1000,H1 :μ<1000 The null hypothesis (H0) typically includes a statement of equality (≥,≤,=), while the alternative hypothesis (H1) contains the opposite inequality. 5 / 20 5. What happens to the mean, median, and mode if each data point in a dataset is multiplied by a constant? A) Mean, Median, Mode all multiply by the constant B) Mean multiplies by the constant, Median multiplies by the constant, Mode remains unchanged C) Mean multiplies by the constant, Median remains unchanged, Mode multiplies by the constant D) Mean remains unchanged, Median multiplies by the constant, Mode remains unchanged When each data point is multiplied by a constant, the mean is affected, but the median and mode remain unchanged. 6 / 20 6. A delivery service has three routes with daily delivery capacities as follows: Route 1: 50 packages, Route 2: 40 packages, Route 3: 30 packages. If each route has a delivery time of 2 hours, what is the primary goal of optimizing the delivery schedule using operational research techniques? A) Minimize the number of routes B) Maximize package capacity C) Minimize delivery time D) Equalize route capacities The primary goal of optimizing the delivery schedule in this scenario is to minimize delivery time, ensuring efficient use of the available delivery capacity on each route. 7 / 20 7. What does the Law of Large Numbers state in the context of statistics? A) A small sample is sufficient to make accurate population-wide inferences. B) The probability of rare events increases with larger sample sizes. C) Larger datasets always lead to more accurate predictions. D) As sample size increases, the variability of sample means decreases. The Law of Large Numbers states that as the sample size increases, the variability of sample means decreases. In other words, larger samples tend to produce more reliable and stable estimates of population parameters, reducing the impact of random fluctuations. 8 / 20 8. You have survey data that includes responses from participants in different age groups regarding their preferred mode of transportation. Which type of chart would be suitable for displaying the distribution of preferences among different age categories? A) Radar Chart B) Box-and-Whisker Plot C) Treemap D) Histogram A Treemap would be suitable for displaying the distribution of preferences among different age categories, providing a visual representation of the relative sizes of each category. 9 / 20 9. Suppose you have data on the distribution of household expenses across different categories, such as rent, utilities, groceries, and entertainment. Which type of chart would effectively represent the proportions of each expense category in the overall budget? A) Bubble Chart B) Area Chart C) Pie Chart D) Donut Chart A Pie Chart would be effective for representing the proportions of each expense category in the overall budget, providing a clear visual depiction of the distribution of expenditures. 10 / 20 10. A study reports a 90% confidence interval for the mean time spent on a task as (15 minutes, 25 minutes). What would happen to the confidence interval if the sample size is increased while keeping other factors constant? A) The interval will shift to the left. B) The interval will become narrower. C) The interval will become wider. D) The interval will remain the same. Increasing the sample size tends to decrease the standard error, making the confidence interval narrower. 11 / 20 11. Imagine you want to compare the market share of different smartphone brands in a specific region. What type of chart would effectively illustrate the percentage distribution of market share for each brand? A) Stacked Bar Chart B) Histogram C) Box Plot D) Bubble Chart A Stacked Bar Chart would be effective for illustrating the percentage distribution of market share for different smartphone brands, showing the contribution of each brand to the total market share. 12 / 20 12. What is the mode corresponding to observations 4,7, 4, 2,7,4, 2,2,7? A) 3 B) 7 C) 4 D) Null data 7, 4, 2 are repeated 3 times each and have the same frequency, so there is no mode; that’s mean 13 / 20 13. A business analyst has prepared a map to show variation in different states. She has labeled sales with S and profit as P with their values and the state name. On what basis has she colored the states? A) Segmentation based on sales values. B) Clusters based on sales values. C) Segmentation based on profit values. D) Clusters based on sales and profit values. Here clusters are formed on both profit and sales values. States with high profit AND sales are in red color, with low sales AND profit are in blue color while others are in orange. This can be seen for Washington and Montana states, even though they have high sales values, they are blue in color because they have low profits. 3.2 Business Visualizations 14 / 20 14. In a standard normal distribution (z-distribution), what is the probability that a randomly selected value falls within one standard deviation of the mean (between -1 and 1)? A) 95.45% B) 68.27% C) 34.13% D) 99.73% In a standard normal distribution, approximately 68.27% of the values fall within one standard deviation of the mean. 15 / 20 15. In a positively skewed distribution, how do the mean, median, and mode compare? A) Mean > Median > Mode B) Median > Mode > Mean C) Mode > Median > Mean D) Mode > Mean > Median In a positively skewed distribution, the mean is pulled in the direction of the skewness, so Mean > Median > Mode. 16 / 20 16. You want to represent the correlation between two variables, such as hours spent studying and exam scores, for a group of students. Which type of chart would help visualize the strength and direction of the relationship? A) Scatter Plot B) Line Chart C) Radar Chart D) Heatmap A Scatter Plot would be suitable for visualizing the correlation between two variables, showing the relationship between hours spent studying and exam scores for individual students. 17 / 20 17. You are tasked with presenting the sales performance of a retail store over the past year. What type of chart would be most appropriate for showcasing monthly sales trends and identifying seasonal patterns? A) Pie Chart B) Scatter Plot C) Bar Chart D) Line Chart A Line Chart would be most appropriate for presenting monthly sales trends and identifying seasonal patterns, as it allows for a clear visualization of the overall trend over time. 18 / 20 18. A researcher calculates a 95% confidence interval for the mean height of a population to be (65 cm, 75 cm). What does this interval signify? A) The researcher is 95% confident that the mean height is exactly 70 cm. B) In 95% of repeated samples, the mean height will fall between 65 cm and 75 cm. C) There is a 95% probability that the true mean height is between 65 cm and 75 cm. D) The mean height is between 65 cm and 75 cm in 95% of the population. The correct interpretation of a 95% confidence interval is that, in 95% of repeated sampling, the calculated interval will capture the true population parameter (mean height in this case). 19 / 20 19. Consider the dataset: 14, 18, 14, 22, 25, 18, 22, 25, 30, 35. What can be said about the mean, median, and mode? A) Mean = 22.9, Median = 22.5, Mode = 14 B) Mean = 22.9, Median = 22, Mode = 14 C) Mean = 22, Median = 22.5, Mode = None D) Mean = 22, Median = 22.5, Mode = 14 Mean = 22 (sum/number of values), Median = 22.5 (middle value of the ordered set), Mode = 14 (most frequent value). 20 / 20 20. A researcher is studying the impact of a new teaching method in a school district and wants to ensure representation from each grade level. What sampling technique is suitable for achieving this goal? A) Cluster Sampling B) Snowball Sampling C) Systematic Sampling D) Stratified Sampling Stratified Sampling would be suitable for ensuring representation from each grade level by dividing the population into strata (grade levels) and then randomly selecting samples from each stratum. Your score is LinkedIn Facebook Twitter VKontakte Restart quiz aboozarkordi
