SOPHIA STATISTICS Introduction to Statistics MILESTONE 1

SOPHIA STATISTICS Introduction to Statistics MILESTONE 1 A survey was conducted to find the frequency with which people go to the movies. A group of 120 people in a mall were asked about how often they go out for a movie and It was found that 36 people go to movies at least once in a month. Which of these is an example of descriptive statistics? Select the correct statement regarding experiments. Scientists want to test a new pair of running shoes. A speed test is performed with two separate groups of participants. The treatment group will wear the new pair of running shoes, while the control group will not. It is believed that age and height may affect speed. Which of the following would be most effective in controlling the confounding variables, such as age and height, in this study? To determine what percentage of 376 teachers at a university were female, Ryan randomly selected 14 teachers. He then collected and analyzed his data. Select the statement that is TRUE. The following shows the Consumer Price Index (CPI) for the years . All of the values use a reference year of 1983. Which of the following is true about the CPI, based on the information? A local bakery conducts a phone survey to find the most popular types of cakes. They selected 100 random phone numbers from the local telephone directory and called them.This type of sampling method is called __________. A poll was conducted two weeks before an election and showed that the incumbent would win with 54% of the vote, with a 3% margin of error. What is the confidence interval for this poll? A scientist is conducting a study on the effect of eating chocolate and overall mood. They believe that gender is a significant factor. The participants are divided by gender. Then, within each group, participants are randomly assigned to consume either chocolate or a placebo and then rate their mood for the day. This experiment will run for two weeks. Which type of experimental design does this situation describe? Which of the following data types will be continuous? The owner of a new store on Main Street wants to turn the boulevard outside into extra parking spaces because she is concerned about parking availability. She randomly selects 500 residents of the town to take a survey, and these individuals have confirmed their participation. One of the survey questions reads, "Many residents believe the lack of available parking on Main Street is a major problem, and extra spaces along the boulevard would help. Do you agree?" The store owner's survey could suffer from which type of bias? Jay wants to study nutrition and performance in schools using available data. Which of the scenarios below will provide Jay with available data? Which of these random samples represents a representative sample of the number of students in a middle school who walk to school? It's Saturday afternoon, and Denise is going shopping. She stops by a department store because she needs a new pair of shoes. She has picked out three styles that she likes. The store associate asks, "What is your shoe size?" Which type of question has the store associate asked? A local gym conducts a survey among the people in a mall. Which survey question would have a qualitative response? The owner of a pizza parlor called every fifth person who ordered pizza last week to rate the pizza. What type of statistical study is this? A factory manufactures motorcycles. One of its employees, working in the quality control department, checks the first 10 and the last 10 motorcycles manufactured in a day. This is what type of sampling? An appliance store manager noted that the sales of home appliances contributed 74% of the store's profits in the year 2010 and 82% in the year 2011. Of the following choices, which statement about home appliance sales is true? Rob sent an email survey to 2,000 cell phone owners asking about their satisfaction with their current plan. Only 256 people returned the survey and they were predominately 18-24 years old. Which of the following statements is true? A travel agency contacted a department store and obtained the list of all people who made purchases using their credit cards at the store in the last month. The agency then surveyed a random sample from the list, calling them to ask their preference for air travel or train travel for taking holidays. Which of the following types of bias affects the conclusions of the survey? A new pet food product for small dogs has been developed to help with tooth decay. Fifty-two dogs participate in the study. Each dog owner picks a card from a standard deck out of a hat. If the card is red, their dog will be in the treatment group. If the card is black, their dog will be in the placebo group. Which experimental design was used? A different coffee seller offered to sell coffee to Jenae's company for half the cost of their current brand. Jenae knew her co-workers were really partial to the coffee they drank now, so she decided to conduct a study to see if they noticed the difference in flavor. Her co-workers were convinced they would. Jenae provided each person with a sample and said that some had the new coffee and some did not. Only Jenae knew who had which brand of coffee. Jenae's strategy is an example of a(n) ________. In a study to assess the risk of obesity with the amount of time exercised per week, researchers matched each patient, in a sample of 500 people who are obese, with a person of the same ethnicity, gender, and age (along with other similar characteristics) who is not obese. The researchers asked the patients and their matches a series of questions, and then tracked eating and exercise habits regularly for several years. Which type of statistical study are the researchers conducting? On a candy production line, 3% of bags are overfilled. An employee randomly selects 100 bags and finds that 5% are overfilled. A second employees takes another random sample of 250 bags and finds that 2% are overfilled. Which of the following explains why there is a difference between the two percentages? James conducts a survey to study the relationship between cell phone use and grades earned during the fall semester. James suspects that there might be a lot of other factors that affect grades besides cell phones. Which of the following could be a confounding variable in James's study? Which of these statements best defines a stratified random sample? In a game, Rachel throws three bean bags, aiming for the hole in the wooden board. Which of the following best classifies the arrangement of bean bags? Jenae's study ignored the fact that only some of her coffee choices had caffeine, even though her co-workers preferred caffeinated coffee. Therefore, Jenae decided to label one type of decaffeinated coffee as having caffeine to see what would happen. As she anticipated, this coffee became more popular with her co-workers, and they claimed that the extra boost of caffeine helped them focus on their work. The growing popularity of the decaffeinated coffee among co-workers, under the false impression that it gave them extra caffeine, is an example of ________. Jenae noticed that many of her co-workers would opt for the coffee that appeared to be most recently brewed, regardless of the flavor of the coffee offered. This leads her to believe that what she was witnessing was not really representative of everyone's true flavor preferences. She adapted her experimental study accordingly. Select one control in Jenae's experimental study. Jessica uses a poorly calibrated stopwatch to note the finish time of a relay race. She noted the time as 125 seconds, whereas the actual time taken was 120 seconds. The percent error in Jessica's calculation is __________.