the power of statistics coursera weekly challenge 5 answers
Test your knowledge: Introduction to hypothesis testing
1. Fill in the blank: The _____ typically assumes that observed data does not occur by chance.
- subjective hypothesis
- objective hypothesis
- null hypothesis
- alternative hypothesis
2. Which of the following statements describe significance level? Select all that apply.
- Significance level is probability of rejecting the alternative hypothesis when it is true.
- Significance level is the threshold at which a result is considered due to chance.
- Significance level is the probability of rejecting a null hypothesis when it is true.
- Significance level is the threshold at which a result is considered statistically significant.
3. What concept refers to the probability of observing results that are at least as extreme as those observed when the null hypothesis is true?
- P-value
- Statistical significance
- Z-score
- Confidence level
4. A data professional conducts a hypothesis test. They mistakenly conclude that their result is statistically significant when it actually occurred by chance. What type of error does this scenario describe?
- Type I
- Type II
- Type III
- Type IV
Test your knowledge: One-sample tests
5. In a one-sample hypothesis test, what does the null hypothesis state?
- The population mean is equal to an observed value.
- The population mean is not equal to an observed value.
- The population mean is less than an observed value.
- The population mean is greater than an observed value.
6. A data professional conducts a hypothesis test. They discover that their p-value is less than the significance level. What conclusion should they draw?
- Decide the test is inconclusive.
- Reject the alternative hypothesis.
- Fail to reject the null hypothesis.
- Reject the null hypothesis.
Test your knowledge: Two-sample tests
7. What does a two-sample hypothesis test determine?
- Whether a sample statistic, such as a mean or proportion, is equal to a specific value
- Whether two population parameters, such as two means or two proportions, are equal
- Whether a population parameter, such as a mean or proportion, is equal to a specific value
- Whether two sample statistics, such as two means or two proportions, are equal
8. What is the null hypothesis of a two-sample t-test?
- There is no difference between two population means
- There is no difference between two population proportions
- The population proportion is equal to an observed value
- The population mean is equal to an observed value
Shuffle Q/A 1
Test your knowledge: Hypothesis testing with Python
9. A data professional can use the Python function scipy.stats.ttest_ind() to compute the p-value for the two-sample t-test.
- True
- False
10. What arguments of the Python function scipy.stats.ttest_ind(a, b, equal_var) refer to observations from the sample data? Select all that apply.
- b
- alpha
- a
- loc