Statistical Studies

A school principal wants to see which subject the 695 students in his school liked best. Which choice BEST represents a representative sample?

• The girls in the school.

• 1 classroom for each grade

• All the students in the school.

• The students making a B in math.

The entire group studied.

• sample

• population

Population or Sample? A quality control engineer is curious about the thickness of paint on a car at her factory. She randomly selects 30 points on the car and measures the paint thickness at each of those points.

• Population

• Sample

Correlation does not imply (blank).

Answer explanation

Two variables can be related without cause and effect being in place. For example, there is a relationship to the number of dog biscuits I eat and the number of walks that I get each day. However, there is no causal relationship.

Linda wanted to know if it is easier for students to memorize a list of common three-letter words (such as fly, pen, and red) than a list of three-letter nonsense words (such as vir, zop, and twq). She randomly selected 𝟐𝟖 students from all tenth graders in her district. She put 𝟏𝟒 blue and 𝟏𝟒 red chips in a jar, and without looking, each student chose a chip. Those with red chips were given the list of common words; those with blue chips were given the list of nonsense words. She gave all students one minute to memorize their lists. After the minute, she collected the lists and asked the students to write down all the words that they could remember. She recorded the number of correct words recalled. What type of study is described?

• Survey

• Experimental Study

• Observational Study

A large high school wants to know the proportion of students who currently arrive to school on time. Academy Administrators asked a random sample of 𝟐𝟎𝟎 students about their arrival times. What type of study is described?

• Survey

• Experimental Study

• Observational Study

A teacher collected data from a random sample of 𝟓𝟎 students in a school district to see if there is a relationship between a student's reading score on a standardized reading exam and their shoe size.

• Survey

• Observational study

• Experimental Study

Match the following

• Observational Study

• measure of observe members of a sample in such a way that they are not affected by the study.

• Survey

• asks everyone of a sample the same set of questions and records the answers.

• Experiment

• Involves applying a treatement to some group or groups and measuring the effects of the treatment

I want to find out how many people in my school like a certain brand of soda, so I watch what all of my friends drink. This is an example of a(n) _​ (a)   .

• Observational Study

• Double Blind Study

• Experiment

• Randomized Trial

Ken wants to compare how many hours a week that sixth graders spend doing mathematics homework to how many hours a week that eleventh graders spend doing mathematics homework. He randomly selects ten sixth graders and ten eleventh graders and records how many hours each student spent on mathematics homework in a certain week.

What study is described?

• Survey

• Experimental Study

• Observational Study