Introductory biostatistics

QUESTION 1

When it comes to comparing mathematics with statistics it is correct to affirm:

• Both areas are independent of context for interpretation.

• In statistics, probabilities lead to inductive interpretation and to uncertain conclusions.

• In both areas, results are either correct or incorrect.

• In both areas, measurements are taken on specific attributes, easy to assess.

Tags

NGSS.HS-LS4-3

QUESTION 2

Which are main sources of bias in a dataset?

• Lack of randomization, measurement inaccuracy and small sample size.

• Large sample size, repetition of measurements and different people sampling.

• Limited access to sample, little time to sample, and individual sample characteristics.

• Low-cost equipment, different people sampling, poor randomization.

QUESTION 3

Which are main measures of data variability?

• Mean values, confidence interval and variance.

• Confidence level, p-value and type-1 error.

• Standard deviation, variance and confidence interval.

• Standard deviation, variance and normal distribution.

QUESTION 4

A normal distribution of data implies that:

• The data are clustered asymmetrically.

• The variability of the data is small.

• Standard deviation and standard error have the same value.

• The majority of the data is around the mean value.

QUESTION 5

A skewed distribution of data implies that:

• The data are clustered symmetrically.

• The variance is high.

• The sampling was probably poorly randomized.

• The distribution follows a bell curve.

QUESTION 6

When it comes to hypothesis in statistics, mark the false:

• One can design as many hypotheses as he desires in the same experiment.

• One hypothesis test can test for as many hypotheses as needed.

• Type-1 errors happens when we see an effect where there is none.

• A hypothesis is only valid if it is testable.

QUESTION 7

Mark the correct about variables:

• Predictive variables are also known as dependent variables.

• Time is always a quantitative variable.

• Seasons are always a qualitative variable.

• Dependent variables cannot be used in hypothesis tests.

QUESTION 8

The p-value is:

• The probability of having different variances.

• The probability of finding an error.

• The probability of having the right result.

• The probability of finding a pattern by chance

QUESTION 9

To perform an Analysis of Variance (ANOVA):

• The variables cannot be independent.

• Data must be normally distributed.

• There must be a finite number of groups to compare.

• The significance level must be of 5 %.

QUESTION 10

A multifactorial ANOVA:

• Tests all the factors isolated and their interaction.

• Tests only for the interaction between factors.

• Tests for various response variables at the same time.

• Needs a significance level of 1 % to be valid.