Lab Assignment #1

1 APPLIED CLINICAL STATS: HLSC 3450 Lab Homework #1 Due: Monday - October 23 rd & Wednesday - October 11 th , 2023 (at the start of lab) The following questions require you to use the LabPractice dataset on Moodle 1) Report the sample size and number of variables in the dataset. Sample Size – 75, Number of variables - 73 2) Obtain information on the appropriate variables to answer the following questions: a) What percentage of this sample is male (gender)? 45.3 % b) What is the mode for religion (religion)? Protestant c) What is the cumulative percentage for 2 years vocational mothers’ education (maed)? 73.3 % d) What proportion of participants have BC grades in high school (grades)? 16 e) How many and what percentage of students took geometry (geo)? 36 students accounting for 48% f) What is the mode, median, and mean for the variable “visualization test” (visual)? Mode – 1, Median – 4.75, Mean – 5.2433 g) What is the average score for match achievement ( mathach )? 12.5645 h) What is the mode (modal category) for ethnicity (ethnic)? What percentage does this group represent? Euro-Amer. 56.2% i) What percentage of students have less A-B and most A-B math grades (mathgr)? How many students belong to each group? Less A-B – 48 students, 58.7%, Most A-B – 31 Students, 41.3% j) What is the average age in the dataset? How does this compare to the median and modal age? Average age – 19.1467, which is higher than the median and mode, both of which are 18. k) Use the variables “visualization test” (visual) and the “visualization retest” (visual2) to answer these questions: i. Which variable has a larger standard deviation? Visualization test has the larger standard deviation. ii. What does the standard deviation tell you about the distribution of the values of the variable? The larger the standard deviation, the greater the spread of values within the data collected and the less powerful that data becomes for use in inferential statistical analysis. l) If you are 1 standard deviation (SD) above the mean for the visualization test (visual), what would be your visualization performance score? 9.15533

2 m) A math achievement score has a mean of 12.5645 and a SD of 6.67031. i. What percentage of the scores is 1 SD above the mean? 34.1% ii. What percentage is 1 SD below the mean? 34.1% n) Scores on the visualization retest are distributed with a mean of 4.5467 and a SD of 3.01816. About 68% of these visualization retest scores fall between …. and ….? 7.56486 and 1.52854 o) Determine the three measures of central tendency (mean, median, & mode) for the variables “visualization test” (visual) and “visualization retest” (visual2). Based on this information, would you describe the distribution of these variables as skewed? If yes, in what direction? Hint: use the normal distribution curve. - Yes, the distribution of both variables are skewed in a positive direction because the mean of both are higher than either their respective medians and modes. 3) Below are some survey questions and responses. What type of data (variable) would they produce based on their respective responses? a) Do you think the flu vaccine offered this winter will protect you from avian flu? o Response 1 (Yes) o Response 2 (No) o Response 3 (Unsure) o Response 4 (Don’t know) Answer…………………………………. Nominal b) How many times a week do you exercise for more than 1/2 hour? o Response 1 (Once) o Response 2 (Twice) o Response 3 (Three times) o Response 4 (Four times or more) o Response 5 (Never) Answer……………………………… Ordinal c) How old were you when you started studying at the University of Lethbridge? o …………………………………. (Scale) Answer…………………………………. 4) When choosing the appropriate level of measurement for a variable . . . a) We use a scale level of measurement for a variable with what type of data? Continuous Data b) We use an ordinal level of measurement for a variable with what type of data? Data that can be categorized AND ordered. c) We use a nominal level of measurement for a variable with what type of data?