Test your knowledge.Receive immediate feedback.You find all answers in the book. Quiz | Basics of Data Analysis /24 59 Quiz | Basics of data analysis 1 / 24 What does an outlier represent in data analysis? A variable that is not important to the model A hypothesis that has been proven A data point that lies an abnormal distance from other values A data point that fits well within the expected range 2 / 24 What is the role of dummy variables in regression analysis? To decrease the variability of the dataset To incorporate nominal data into the model To account for variable transformations To increase the complexity of the model 3 / 24 Which statements about statistical parameters are correct? The mean of standardized data is always 1. The correlation coefficient results from the square root of the variance. The sum of the deviations from the arithmetic mean is always zero. For normally distributed data, the following applies: mean=median=mode Only for standardized data a standard deviation can be calculated. 4 / 24 What describes an ordinal scale? A scale that allows only classifications A scale without equal segments A scale that allows a ranking order A scale with a natural zero point 5 / 24 What does the alternative hypothesis suggest in a statistical test? No change or effect is expected. The observations are random. A change or effect contrary to the null hypothesis is expected. The data is insufficient for analysis. 6 / 24 In statistical hypothesis testing, what represents the risk of rejecting a true null hypothesis? Confidence level p-value Significance level (α) Beta error 7 / 24 What statistical method divides the difference between the observed and hypothetical mean by the standard error of the mean? Chi-square test F-test T-statistic Z-test 8 / 24 What does a two-tailed t-test in hypothesis testing involve? Both positive and negative deviations from the mean are considered Only negative deviations from the mean are considered Neither positive nor negative deviations from the mean are considered Only positive deviations from the mean are considered 9 / 24 What type of analysis is most appropriate for understanding the effect of different levels of a nominal independent variable on a metric dependent variable? Correlation analysis Factor analysis Regression analysis Analysis of variance (ANOVA) 10 / 24 The difference between correlation and causality is that … causality does not require information about the origin of the data. causality is always based on a correlation, but not vice versa. a correlation is always positive, whereas with causality negative values are also possible. in causality there is always a cause-effect-relationship between variables, while correlation only expresses the strength of an undirected relationship between two variables. 11 / 24 What do the 'whiskers' in a boxplot typically represent? Maximum and minimum values excluding outliers First and third quartiles The standard deviation of the dataset Mean and median values 12 / 24 In data analysis, what is meant by 'interval estimation'? Calculating the mean and standard deviation Estimating a single point value for a parameter Determining the range within which a parameter lies with a certain probability None of the above 13 / 24 What statements are correct? Analysis of variance (ANOVA) belongs to the structure-describing methods. Cluster analysis and factor analysis belong to the structure-testing methods. Cluster analysis and factor analysis aim to summarize data. Contingency analysis and discriminant analysis differ only with regard to the required scale level of the independent variables. Regression analysis is also called the "mother" of multivariate methods. 14 / 24 Which of the following methods do not allow to detect outliers? Boxplots Calculation of the mean Calculation of the median Standardization of data Histograms 15 / 24 How does multivariate analysis differ from bivariate analysis? It considers only two variables at a time. It does not involve statistical testing. It considers more than two variables at a time. It only uses categorical data. 16 / 24 Which percentile is represented by the bold horizontal line in a boxplot? 50th percentile 100th percentile 25th percentile 75th percentile 17 / 24 What is the primary purpose of conducting a statistical test for means? To identify if the difference in means is due to random variation or represents a real change To calculate the standard deviation of the dataset To confirm that data collection methods are valid To visually represent the data distribution 18 / 24 What is meant by the centering property of the mean? Check 19 / 24 What best describes a factor analysis? It describes the variance between groups. It tests the relationship between variables. It discovers structures within datasets. It tests the effect of independent variables on dependent variables. 20 / 24 Which of the following scale levels allows for the most arithmetic operations? Nominal scale Interval scale Ordinal scale Ratio scale 21 / 24 What scale level is required for the application of the t-test? Ordinal scale Ratio scale Nominal scale Interval scale 22 / 24 What is a dummy variable? A variable that takes only the values 0 or 1 A variable that takes all values between 0 and 1 A continuous variable A variable without influence 23 / 24 What is the primary difference between exploratory and confirmatory factor analysis? Confirmatory factor analysis tests a predefined structure Exploratory factor analysis uses only metric data Exploratory factor analysis cannot identify factors Confirmatory factor analysis does not use mathematical models 24 / 24 What is meant by the 'significance level' in hypothesis testing? The level at which data aligns with the predicted outcomes The mean value of the data The probability of wrongly rejecting the null hypothesis The probability of the hypothesis being true Your score is 0% Restart quiz Learn more…MethodsServiceAbout us ContactFeedbackOrder data etc. GeneralImprintPrivacy notice
