Quantitative Quiz 16MarkMarch 7, 2025Quantitative Aptitude Welcome to your Quantitative Quiz 16 What is the purpose of the F-test in statistics? To compare the means of two groups To compare the variances of two or more groups To test the correlation between two variables To estimate the population mean None Which of the following is a feature of a normal distribution? It is asymmetric It has a skewed tail The mean, median, and mode are all equal It has a single peak (unimodal) None Which of the following is true about a p-value of 0.05 in hypothesis testing? The null hypothesis is definitely true The probability of making a Type I error is 5% The null hypothesis should always be accepted There is no significant relationship between variables None Which type of probability distribution is used to model the number of successes in a fixed number of trials? Poisson distribution Normal distribution Binomial distribution Exponential distribution None What does a Z-score of 2 represent? The data point is 2 standard deviations below the mean The data point is 2 standard deviations above the mean The data point is exactly at the mean The data point is twice as large as the mean None Which of the following is a key assumption in linear regression? The dependent variable is categorical The relationship between variables is non-linear There is no correlation between the dependent and independent variables The errors are normally distributed and independent None What does the term "multicollinearity" refer to in regression analysis? When the dependent variable is categorical When independent variables are highly correlated with each other When the regression model is linear When there is no correlation between the independent variables None What is the primary use of a histogram? To show the distribution of a dataset To measure the central tendency of a dataset To calculate the mean of a dataset To calculate the probability of an event None What does the standard deviation measure? The average value of the dataset The middle value in a sorted dataset The spread or dispersion of the data points around the mean The highest value in a dataset None Which of the following tests is used to determine if a sample comes from a normally distributed population? T-test Z-test Kolmogorov-Smirnov test Chi-square test None What is a Type I error in hypothesis testing? Rejecting a true null hypothesis Accepting a false null hypothesis Incorrectly concluding that there is no relationship Incorrectly concluding that the results are significant None What does the term "power of a test" refer to? The probability of accepting the null hypothesis when it is true The probability of rejecting the null hypothesis when it is false The probability of making a Type II error The probability of making a Type I error None Which of the following best describes the term "confounding variable"? A variable that is independent of the study variables A variable that is not controlled for and may affect the results A variable that is used to randomize the study groups A variable that causes the dependent variable to change directly None What does the chi-square goodness of fit test measure? The difference between observed and expected frequencies The relationship between two continuous variables The correlation between two categorical variables The difference between two sample means None Which of the following is an assumption of the Central Limit Theorem? The sample size must be greater than 100 The population must be normally distributed The population mean must be known The sample mean must be greater than the population mean None In a dataset, if the distribution is skewed to the right, which measure of central tendency is the largest? Mean Median Mode Range None Which type of data is appropriate for the use of a bar chart? Continuous data Categorical data Ordinal data Both categorical and ordinal data None Which of the following tests would be used to compare the proportions of two independent groups? Paired T-test Z-test for proportions One-way ANOVA Chi-square test for independence None What is the key feature of a Poisson distribution? It is used to model the time between events It models the number of occurrences of an event in a fixed interval of time or space It is symmetric about the mean It assumes a normal distribution None Which of the following is a property of the normal distribution? It has two modes It is symmetric around the median It is positively skewed It is negatively skewed None What does the correlation coefficient measure? The strength and direction of the linear relationship between two variables The mean of the dataset The spread of data in a sample The probability of an event occurring None What is the formula for calculating the coefficient of variation (CV)? CV= standard deviation / mean CV= variance / mean CV= standard deviation / mean ×100 CV= median / range None Which of the following statements is true about the exponential distribution? It is used to model the number of successes in a fixed number of trials It models the time between events in a Poisson process It is always positively skewed It is used to model categorical data None What is the purpose of a control chart in statistical quality control? To plot the relationship between two variables To monitor the performance of a process over time To compare means between multiple groups To calculate the correlation between two variables None In a scatter plot, what does a straight line with a positive slope indicate? No relationship between the variables A positive linear relationship between the variables A negative linear relationship between the variables A curvilinear relationship between the variables None What does a 95% confidence interval mean? There is a 95% chance that the sample mean is within the interval There is a 95% chance that the population parameter is within the interval The interval contains 95% of all sample data The interval has a 95% probability of being skewed None In hypothesis testing, what is a Type II error? Failing to reject a false null hypothesis Rejecting a true null hypothesis Correctly rejecting a true null hypothesis Correctly failing to reject a false null hypothesis None Which of the following is the most appropriate test for comparing the means of two related groups? Independent samples t-test Paired samples t-test One-way ANOVA Chi-square test None Which of the following best describes a positively skewed distribution? The right tail is longer than the left tail The mean is smaller than the median The distribution is symmetrical The mode is greater than the median None Which of the following is the primary purpose of the ANOVA test? To compare the variance of two or more groups To compare the means of two or more groups To assess the strength of the relationship between variables To test the significance of correlations None 1 out of 6 Time's upTime is Up! Post Views: 112
