BioStats HCD300 HW 1-4

Which of the correlations is the weakest?

-0.25

Place the following operations into the proper order in which they would be performed.

1) parenthesis 2) exponents 3) multiplication 4) addition

In a box, there are 8 red, 7 blue and 6 green balls. One ball is picked up randomly. What is the probability that it is neither red nor green?

1/3

What is the variance (s2) of the following set of scores? 10, 15, 12, 18, 19, 16, 12

11.29

Given the following data for resting heartrate among college students, what is the IQR? 57, 59, 60, 62, 62, 63, 64, 68, 70, 70, 71, 71, 73, 79, 87, 89, 90

14

Calculate the mean of the following set of scores: 10, 15, 12, 18, 19, 16, 12

14.57

A group of 262 students was polled to determine whether they exercise regularly (engaging in moderate activity for 30-60 min, 3 or more times per week). Use the following table to answer questions 6-11: Exercises Regularly Gender Female male total no 72 96 168 yes 58 36 94 Total 130 132 262 What was the sample size of this study

262

What is the standard deviation (s) of the following set of scores? 10, 15, 12, 18, 19, 16, 12

3.36

If you choose a person from the survey at random, what is the probability that the person exercises regularly?

35.88%

If you choose a person from the survey at random, what is the probability that the person is a male who does not exercise regularly?

36.64%

If you choose a person from the survey at random, what is the probability that the person is male, given that the person exercises regularly?

38.3%

If you choose a person from the survey at random, what is the probability that the person is female?

49.62%

If you have a set of scores with a range of 50 and you want 10 intervals, what should be the size of your class interval?

5

What is the range of the following set of scores? 10, 15, 12, 18, 19, 16, 12

9

What is a function in Excel?

A predefined formula

Reliability is concerned with:

Consistency

Which of the following is concerned with monitoring estimates of present performance and predictions of future performance?

Criterion validity

Which of the following refers to the type of statistical methods used to organize and describe the characteristics of a dataset?

Descriptive statistics

Jennifer is thinking of moving into a new neighborhood that is closer to campus. Before signing a lease, she checks the number of robberies in the neighborhood. What type of variable is the number of robberies reported in the neighborhood during the last year?

Discrete

True or False, the misuse of statistics is always intentiona

False

True or False, the probability of an outcome can be a negative number.

False

Which of the following is an example of a continuous variable?

Family Income

Which of the following would be appropriate to use when displaying continuous interval/ratio data? (choose one or more)

Histogram, scatterplot, box and whisker plot

Which of the following refers to the type of statistical methods used to draw conclusions about the population based on a sample?

Inferential Statistics

Which of the following is designed to present large amounts of information quickly, and uses pictures or shapes to display the information?

Infographic

What level of measurement is the Centigrade temperature scale?

Interval

If you were interested in tracking your GPA during the time you are in graduate school, which of the following might you use?

Line chart

When using the AVERAGE function in Excel, which of the following are you calculating?

Mean

Which measure(s) of central tendency is(are) affected by outliers? (Choose one or more)

Mean

Which of the following measures of central tendency can be used for nominal level data? (choose one or more)

Mode

A survey for kindergartners asked about their favorite color. The children were asked to check the box corresponding to blue, red, green, yellow, or orange. What is the scale of measurement for this question?

Nominal

What is the term associated with scores that are at the extreme ends of the distribution?

Outliers

High school class rank is highly correlated with college GPA. This is an example of what type of validity?

Predictive validity

You collect blood pressure readings from 150 patients. What type of data is this?

Quantitative

The three measures of variability commonly used to reflect the spread or dispersion in a group of scores are the standard deviation, the variance, and the _________?

Range

In Excel, which of following functions adds a set of numbers

SUM

A ________ is a subgroup of people taken from the ________ that you wish to study.

Sample, Population

Hospital administrators want to determine the average satisfaction for patients receiving care in the ER over the last month. The list of all ER patients over the last month is entered into a computer program which uses an algorithm to randomly select 100 patients. Surveys are then sent to those patients. What type of sampling method is this?

Simple random

According to our class lecture, which of the following is not a way that statistics may be misleading?

Skewed Curves

What does the notation ∑ mean?

Sum

If a measure is consistent over multiple occasions, what type of reliabiility does the test have?

Test-retest reliability

True or False, the sum of the deviations from the mean will always equal 0.

True

What is obtained by squaring the standard deviation?

Variance

Validity is concerned with:

accuracy

What term describes the groups that you divide your data into when creating a histogram? (choose one or more)

bin, class interval, class width

Researchers administer an IQ test to a group of high school students. They then correlate the scores on the IQ test with the student's current high school GPA. This is an example of what type of validity?

concurrent validity

Researchers want to determine the percentage of students who own iPhones and Android cell phones. They go to a popular spot on campus and ask first 100 students who pass what type of cell phone they own. What type of sampling method is this?

convenience

A positive correlation means that there is a strong relationship between the variables.

false

If there is a strong correlation between two variables (x and y) it is safe to assume that x caused y.

false

True or False, box plots are not affected by outliers.

false

True or False, in ordinal measurement the distance between the values has meaning.

false

True or False, reliability refers to whether we are truly measuring what we are trying to measure.

false

Which of the following are nominal data

five categories of race, two categories of exposure to a treatment (exposed and unexposed)

Which of the following tells you how often a certain score occurs?

frequency distribution

Which of the following is not one of the 5 number summary?

mean

Which of the following descriptive statistics can be used for interval data? (choose one or more)

mean, mode, standard deviation, variance

Which of the following would be appropriate to display nominal data? (choose one or more)

pie chart, bar graph

Researchers collect data about JUULing by asking users to keep track of the number of times per day they turn their device on and the number of inhalations each time they turn the device on. What type of data are these?

ratio

Probability is an important concept for researchers primarily because

researchers collect data from samples rather than populations

In statistics, what does the letter "n" represent?

sample size

A researcher divided subjects into two groups according to gender and then selected members from each group for her sample. What sampling method was the researcher using

stratified

Mathematically, probability may be defined as

the number of ways an outcome may occur divided by the total number of possible outcomes

A perfect negative correlation would be represented by Pearson's r of -1.

true

True or False, if the probability of an event happening is 25%, then the probability of it not happening is 75%.

true

True or False, in interval measurement the distance between the values has meaning.

true