Unit 1
What is the definition of a population in statistics?
What is the entire group of individuals or instances about whom we hope to learn.
What is the mean of the following data set: 4, 8, 6, 5, 3?
What is 5.2.
What is the probability of drawing a red card from a standard deck of 52 playing cards?
what is 1/2 or .5
What is the probability of rolling a sum of 7 with two six-sided dice?
what is 1/6
What is the difference between a sample and a population?
What is A sample is a subset of a population, selected for the purpose of conducting a study. While a population includes all members of a specified group, a sample includes only a portion of that group.
What is the median of the following data set: 12, 15, 10, 22, 18?
what is 15.
Explain the concept of sampling bias and provide an example.
What is the sample collected is not representative of the population from which it is drawn, leading to inaccurate conclusions
What is the definition of a sampling distribution in the context of statistics?
What is the probability distribution of a statistic (like the sample mean or sample proportion) obtained from a large number of samples drawn from a specific population.
What is a simple random sample, and why is it important?
What is a sampling method where each member of the population has an equal chance of being selected. This is important because it helps to eliminate bias in the selection process, ensuring that the sample accurately represents the population.
Calculate the standard deviation of the following data set: 5, 7, 3, 9, 11.
What is √8 or Approx. 2.83
What is the mean and standard deviation of the following dataset: 5, 10, 15, 20, 25?
what is 16
A sample of 30 students has a mean test score of 75 with a standard deviation of 10. Calculate a 95% confidence interval for the population mean.
What is the 95% confidence interval for the population mean is (71.26,78.74).
Calculate the mean of the following data set: 5, 10, 15, 20, 25.
What is 15
What is the 75th percentile (Q3) of the following data set: 2, 3, 5, 7, 8, 10, 12?
What is 10
What is the Central Limit Theorem, and why is it important in statistics?
what is the distribution of the sample means will approach a normal distribution as the sample size increases, regardless of the shape of the population distribution.
A manufacturer claims that their light bulbs last an average of 1200 hours. A sample of 50 bulbs shows a mean life of 1150 hours with a standard deviation of 200 hours. Test the manufacturer’s claim at the 0.05 significance level.
What is the standard deviation of the following data set: 4, 8, 6, 5, 3?
What is 26/5 or 5.2.
Given the following data set: 1, 2, 2, 3, 4, 4, 4, 5, 6, 7, what is the mode?
What is 4.
Describe the difference between Type I and Type II errors in hypothesis testing.
a Type I error occurs when the null hypothesis is rejected when it is actually true. A Type II error occurs when the null hypothesis is not rejected when it is false.
In a study of 200 adults, researchers recorded their smoking habits and whether they developed lung cancer. The results are as follows:
Smoking status Cancer No Cancer
Smoker 40 60
NonSmoker 20 80
Test if smoking status is independent of lung cancer at the 0.05 significance level.
What is there is sufficient evidence to conclude that smoking status is not independent of lung cancer.