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 In statistical hypothesis testing, what represents the risk of rejecting a true null hypothesis? p-value Beta error Confidence level Significance level (α) 2 / 24 What is a dummy variable? A variable that takes only the values 0 or 1 A variable without influence A continuous variable A variable that takes all values between 0 and 1 3 / 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? Regression analysis Factor analysis Analysis of variance (ANOVA) Correlation analysis 4 / 24 What does an outlier represent in data analysis? A variable that is not important to the model A data point that lies an abnormal distance from other values A hypothesis that has been proven A data point that fits well within the expected range 5 / 24 What is the primary purpose of conducting a statistical test for means? To confirm that data collection methods are valid To calculate the standard deviation of the dataset To visually represent the data distribution To identify if the difference in means is due to random variation or represents a real change 6 / 24 Which of the following methods do not allow to detect outliers? Calculation of the mean Histograms Boxplots Standardization of data Calculation of the median 7 / 24 In data analysis, what is meant by 'interval estimation'? None of the above Estimating a single point value for a parameter Determining the range within which a parameter lies with a certain probability Calculating the mean and standard deviation 8 / 24 What scale level is required for the application of the t-test? Interval scale Ordinal scale Nominal scale Ratio scale 9 / 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. Regression analysis is also called the "mother" of multivariate 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. 10 / 24 What is meant by the centering property of the mean? Check 11 / 24 The difference between correlation and causality is that … causality does not require information about the origin of the data. 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. causality is always based on a correlation, but not vice versa. 12 / 24 Which percentile is represented by the bold horizontal line in a boxplot? 100th percentile 25th percentile 75th percentile 50th percentile 13 / 24 What best describes a factor analysis? It describes the variance between groups. It tests the relationship between variables. It tests the effect of independent variables on dependent variables. It discovers structures within datasets. 14 / 24 Which statements about statistical parameters are correct? The mean of standardized data is always 1. For normally distributed data, the following applies: mean=median=mode Only for standardized data a standard deviation can be calculated. The correlation coefficient results from the square root of the variance. The sum of the deviations from the arithmetic mean is always zero. 15 / 24 What describes an ordinal scale? A scale that allows only classifications A scale without equal segments A scale with a natural zero point A scale that allows a ranking order 16 / 24 What is the role of dummy variables in regression analysis? To decrease the variability of the dataset To account for variable transformations To increase the complexity of the model To incorporate nominal data into the model 17 / 24 What does a two-tailed t-test in hypothesis testing involve? Only positive deviations from the mean are considered 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 18 / 24 What is the primary difference between exploratory and confirmatory factor analysis? Confirmatory factor analysis tests a predefined structure Exploratory factor analysis cannot identify factors Confirmatory factor analysis does not use mathematical models Exploratory factor analysis uses only metric data 19 / 24 How does multivariate analysis differ from bivariate analysis? It considers more than two variables at a time. It does not involve statistical testing. It considers only two variables at a time. It only uses categorical data. 20 / 24 What does the alternative hypothesis suggest in a statistical test? No change or effect is expected. A change or effect contrary to the null hypothesis is expected. The observations are random. The data is insufficient for analysis. 21 / 24 What statistical method divides the difference between the observed and hypothetical mean by the standard error of the mean? Z-test Chi-square test T-statistic F-test 22 / 24 What is meant by the 'significance level' in hypothesis testing? The probability of wrongly rejecting the null hypothesis The probability of the hypothesis being true The level at which data aligns with the predicted outcomes The mean value of the data 23 / 24 Which of the following scale levels allows for the most arithmetic operations? Interval scale Nominal scale Ratio scale Ordinal scale 24 / 24 What do the 'whiskers' in a boxplot typically represent? The standard deviation of the dataset Mean and median values Maximum and minimum values excluding outliers First and third quartiles Your score is 0% Restart quiz Learn more…MethodsServiceAbout us ContactFeedbackOrder data etc. GeneralImprintPrivacy notice
