#1
In a normal distribution, what percentage of data falls within one standard deviation of the mean?
68%
ExplanationApproximately 68% of data points in a normal distribution lie within one standard deviation of the mean.
#2
What does the term 'p-value' stand for in statistics?
Probability-value
ExplanationThe p-value represents the probability of obtaining the observed results, or more extreme results, under the assumption that the null hypothesis is true.
#3
Which measure of central tendency is most affected by outliers?
Mean
ExplanationMean is sensitive to extreme values, making it highly affected by outliers.
#4
What does the standard deviation measure in a set of data?
Variability
ExplanationStandard deviation quantifies the spread or dispersion of data points from the mean, representing variability.
#5
Which graphical representation is suitable for displaying the distribution of a continuous variable?
Histogram
ExplanationHistograms provide a visual depiction of the frequency distribution of continuous data, showing the shape, center, and spread of the data.
#6
What is the purpose of a confidence interval in statistics?
To estimate the population parameter with a range of values
ExplanationConfidence intervals provide a range of values within which the true population parameter is estimated to lie with a certain level of confidence.
#7
Which statistical test is appropriate for comparing means of more than two independent groups?
Analysis of Variance (ANOVA)
ExplanationANOVA assesses whether the means of multiple independent groups are significantly different from each other.
#8
In a normal distribution, what is the relationship between the mean, median, and mode?
Mean = Median = Mode
ExplanationIn a perfectly symmetrical normal distribution, the mean, median, and mode are equal.
#9
Which statistical test is used to determine if there is a significant association between two categorical variables?
Chi-square test
ExplanationChi-square test assesses the independence between categorical variables by comparing observed and expected frequencies.
#10
What is the purpose of regression analysis in statistics?
To predict one variable based on another
ExplanationRegression analysis aims to establish the relationship between variables, allowing prediction based on known data.
#11
What does p-value represent in hypothesis testing?
Probability of obtaining the observed results if the null hypothesis is true
ExplanationP-value indicates the likelihood of observing the given results if the null hypothesis were correct, guiding decision-making in hypothesis testing.
#12
What is the primary advantage of using a box plot in data visualization?
Highlights outliers in the data
ExplanationBox plots visually represent the distribution of data, emphasizing outliers and providing insight into the data's spread and central tendency.
#13
What is the purpose of the coefficient of determination (R-squared) in regression analysis?
To evaluate the goodness of fit of the regression model
ExplanationR-squared measures the proportion of variance in the dependent variable explained by the independent variables, indicating the goodness of fit of the regression model.
#14
What does a two-tailed hypothesis test assess?
If there is a significant difference in both directions
ExplanationA two-tailed hypothesis test determines if there is a significant difference in either direction from the hypothesized value.