Data Collection Methods
The entire group a researcher is interested in/
What is a Population?
Repeating data in multiple columns or rows, missing data, & data given in different units are all examples of this.
What is Messy Data?
The percent of data within 2 standard deviations of the mean
What is 95%?
The Z-Score Formula
What is (Data - \mu \ ) / σ ?
This is the greatest possible distance between the estimate and the value of the parameter it is estimating.
What is the Margin of Error?
A coach wants to know how many calories their athletes are eating in a day. They ask the athletes to write down all they ate in the past 24 hours to calculate the total number of calories consumed. This is an example of what type of investigation?
What is an Observational Study?
This involves ensuring any data collected is kept confidential and securely stored. Participants must be assured that their personal data is secure and their participation will be kept anonymous.
What is Data Privacy?
From left to right, the 8 percentages of the individual sections of the Empirical Rule.
What is 0.15%, 2.35%, 13.5%, 34%, 34%, 13.5%, 2.35%, 0.15%?
On a standardized exam, the scores are normally distributed with a mean of 300 and a standard deviation of 40. Find the z-score of a person who scored 310 on the exam.
What is 0.25?
A survey was given to a random sample of 250 voters in the United States to ask about their preference for a presidential candidate. Of those surveyed, 175 respondents said that they preferred Candidate A. At the 95% confidence level, what is the margin of error for this survey expressed as a proportion to the nearest thousandth?
What is 0.058?
What type of data is being used if a researcher pulls data from a national database?
What is Secondary Data?
This involves translating raw data into usable information by cleaning and organizing it.
What is Data Processing?
The percentage of data between 3 standard deviations below the mean and 2 standard deviations above the mean.
What is 97.35%?
When Khloe runs the 400 meter dash, her finishing times are normally distributed with a mean of 81 seconds and a standard deviation of 1 second. What percentage of races will her finishing time be slower than 83 seconds, to the nearest tenth?
What is 2.3%?
A study by the department of education of a certain state was trying to determine the mean SAT scores of the graduating high school seniors. The study examined the scores of a random sample of 90 graduating seniors and found the mean score to be 503 with a standard deviation of 108. At the 95% confidence level, use the normal distribution / empirical rule to estimate the margin of error for the mean, rounding to the nearest tenth.
What is 22.8?
Your math teacher wants to survey the class. They select every 5th student who walks into the class. This is an example of what type of randomization?
What is Systematic?
Any difference between the sample result and the truth about the population
What is Bias?
The weight of oranges growing in an orchard is normally distributed with a mean weight of 8 oz. and a standard deviation of 1.5 oz. Using the empirical rule, this interval would represent weights of the middle 99.7% of all oranges from this orchard.
What is 3.5 & 12.5?
Student A scored a 1250 on the SAT, and Student B scored a 32 on the ACT. The mean SAT score in 2024 was 1090 with a standard deviation of 135. The mean composite ACT score in 2025 was 21.6 with a standard deviation of 4.2.
What were the students' Z-Scores & which student performed better relative to their test?
What is 1.19, 2.48, Student B?
A survey was given to a random sample of 950 residents of a town to determine whether they support a new plan to raise taxes in order to increase education spending. Of those surveyed, 380 respondents said they were in favor of the plan. Determine a 95% confidence interval for the proportion of people who favor the tax plan, rounding values to the nearest thousandth.
What is (0.368,0.432)?
To determine the theme for homecoming, SGA wants to survey the junior class. They divide the junior class up by advisement and randomly select 5 students from each junior advisement class to survey. This is an example of what type of randomization?
What is Stratified?
A researcher wants to know if giving extra water to his outdoor flowers increases their rate of growth. In Spring, he gives all his flowers under the shade of his porch an extra liter of water a week. At the end of Spring, he measures how much all his flowers have grown.
Plants growing differently in the shade than the sun could be an example of what?
What is a Confounding Variable?
On a test that has a normal distribution, a score of 58 falls one standard deviation above the mean, and a score of 64 falls three standard deviations above the mean. Determine the mean of this test.
What is 55?
Hunter earned a score of 340 on Exam A that had a mean of 300 and a standard deviation of 20. He is about to take Exam B that has a mean of 48 and a standard deviation of 5. How well must Hunter score on Exam B in order to do equivalently well as he did on Exam A? Assume that scores on each exam are normally distributed.
What is 58?
A study by the department of education of a certain state was trying to determine the mean SAT scores of the graduating high school seniors. The study examined the scores of a random sample of 84 graduating seniors and found the mean score to be 462 with a standard deviation of 81. Use the normal distribution/empirical rule to estimate a 95% confidence interval for the mean, rounding all values to the nearest tenth.
What is (444.3,479.7)?