Question

24 D) for confounding variable are the following valid? education level, income, socio economic, and peer pressure?

25) is parameter correct ?

a high school degree; high school degree; more than high school degree. 24) A researcher wants to investigate a correlation between meth use as a teen, and having marital problems as an adult a) Identify the population b) What are the two groups that are being compared? c) What is the explanatory variable? What is the response? d) Find a confounding variable. e) Which type of study is more appropriate: observational or experimental? Justify your answer 25) A study finds that the average cost of a gym membership in the US is S34 a month. Is S34 a parameter or statistic? Justify your ans wer. 26) (3 points) Locate te mean, median and mode for the graph shown below: Median__ e Mean 27) In how many ways can 8 people be arranged for a photograph session? 28) Identify the sampling technique used in the following study: In an effort to determine customer satisfaction Delta Airline randomly select 59 flights during certain week and survey all passengers on thos e flights. 29) Suppose 40 cars start at a car race. How many ways can the top three cars finish the race? 30) A machine has a probability 0.03 of producing a defective golf ball. When 3 golf balls are manufactured by this machine, find the probability that none of the golf balls is defective. 31) When three people are selected randomly, find the probability that their birthdays are all different. 32) The mean credit card debt for college students in the U.S. is $2100. Is 2100 a parameter or statistic? Justify your answer 33) How many different outcomes are possible when 3 dice and 2 coins are tossed? 34) Determine whether the following events are a) disjoint b) independent or dependent

Answer 1

ANS- 24(D)

Firstly introduce

Confounding variable- A confounding variable is an “extra” variable that you didn’t account for. They can ruin an experiment and give you useless results. They can suggest there is correlation when in fact there isn’t. They can even introduce bias. That’s why it’s important to avoid getting them into your experiment.In an experiment, the independent variabletypically has an effect on your dependent variable. For example, if you are researching whether lack of exercise leads to weight gain, lack of exercise is your independent variable and weight gain is your dependent variable. Confounding variables are any other variable that also has an effect on your dependent variable. They are like extra independent variables like age that are having a hidden effect on your dependent variables like .

✓ Geographic location, family functioning, parental alcohol abuse, and lifetime use of marijuana, crack/cocaine, and inhalants were all independently associated with increased risk of lifetime meth use by teen. Social economic and education level are confounded variable which has an effect on meth use by teen.

Ans-25

Parameter is a population constant that describes the population. Eg. population mean, population variance etc.

Statistic is function of sample values which is a characteristic of sample . Eg. Sample mean, sample variance etc.

✓ Hera the average cost of Gym membership in US is 34$ that is fixed and representing the whole US Gym membership.

Hence $34 is representing the parameter.