Explore BrainMass

Explore BrainMass

    Type I and Type II Errors

    BrainMass Solutions Available for Instant Download

    Hypothesis Testing of Sprinklers

    I need some help reviewing the sample problem below: Sprinkler Systems. A manufacturer of sprinkler systems designed for fire protection claims that the average activating temperature is at least 135 degrees F. To test this claim, you randomly select a sample of 32 systems and find the mean activation temperature between 133

    Hypothesis Testing & Confidence Interval for Cavity Prevelance

    The producers of a new toothpaste claim that it prevents more cavities than other brands of toothepaste. A random of 60 people used the new toothpaste for 6 months. The mean number of cavities at their next check up is 1.5. In the general population, the mean number of cavities at a 6 month checkup is 1.73 (population mean = 1.1

    Explaining the Z test for proportion

    A researcher believes that the percentage of people who exercise in California is greater than the national exercise rate. The national rate is 20%. The researcher gathers a random sample of 120 individuals who lives in CA and finds that the number who exercises regularly is 31 out of 120. a. What is X2 obt? b. What is the df

    One-way ANOVA between 3 Treatments

    One of the primary advantages of a repeated-measures design, compared to an independent-measures design, is that it reduces the overall variability by removing variance caused by individual differences. The following data are from a research study comparing three treatment conditions. (see attached file) 1. Assume that the data

    Defining statistical concepts

    Define each of the following and provide a specific example for each type of statistical test or concept. - The null and alternative hypotheses - Type I and Type II errors - The proper use of statistical software - Cross-tabulation - Chi-Square - Single sample t-test - Independent t-test - One-Way ANOVA Show y

    Hypothesis Testing & Confidence

    Question 1: Hypothesis testing allows you to verify whether a supposition is correct. By considering the variables, you may also be able to analyze the reason why the hypothesis is proven correct or incorrect. Describe in your own words the differences between type I and type II errors. In addition to your explanation, you ma

    Standard Deviation, Hypothesis and Standard Error

    Why is it important to know the standard deviation for a given sample? What do researchers learn about a normal distribution from knowledge of the standard deviation? A sample of n=20 has a mean of M = 40. If the standard deviation is s=5, would a score of X= 55 be considered an extreme value? Why or why not? Can you please d

    Stratification

    Could you please explain Stratification to me in layman's terms and then read the attached article and detail how it was used therein? Reference: Lipchik, G. L., Nicholson, R. A., & Penzien, D. B. (2005). Allocation of patients to conditions in headache clinical trials: randomization, stratification, and treatment matching.

    Hypothesis Testing and Type I and Type II Errors

    Please help with the following problems. 1. Whether the appropriate analysis would be a one or two tailed test 2. A type I and type II error given the context of the hypothesis. The Hypothesis A. Cognitive behavior therapy (CBT) will be better than supportive therapy in reducing children's anxiety at posttreatment.

    Type I and Type II Errors and Controllable Factors

    Define a type I error and explain why it occurs. Explain a factor that the researcher can control to change the type I error. Also, explain how type I errors can be avoided. Define a type II error and explain why it occurs. How do sample size, selection of alpha level, and precision of measurement affect the type II error rat

    Type I and Type II Errors

    In the last few years, an organization has conducted 200 clinical trials to test the effectiveness of anti-anxiety drugs. Suppose, however, that all of those drugs were obtained from the same fraudulent supplier, which was later revealed to have been sending only inert substances (e.g., distilled water, sugar pills) instead of r

    Type I and Type II Errors in Everyday Life

    I need a real-world situation where Type I and Type II errors can occur and state the null and alternative hypotheses for that example. Could you please also explain what the Type I and Type II errors are for that example?

    Type I vs Type II Error

    Please explain the difference between a Type I and a Type II error when testing a hypothesis. Please provide an example of each.

    Intelligence Test, One-Tailed vs. Two-Tailed, Type I and Type II Error

    1. The SEM for a particular intelligence test (mean of 100, standard deviation of 15) is 3 points. Ken Garoo obtains an IQ score of 126, but needs an IQ of 130 to qualify for a Talented and Gifted (TAG) class. Calculate the range of Ken's true score: (a) with 68% probability, and (b) with 95% probability. Should Ken be admitted

    Hypothesis Testing: One population

    Please help with the following problem. In the US legal system, a defendant is presumed innocent until proven guilty. Consider a null hypothesis, Ho: that the defendant is innocent, and an alternative hypothesis, Ha: that the defendant is guilty. Explain the meaning of a jury committing a Type I error and of committing a Ty

    Type I and II errors and Confidence interval

    1. You have been asked to evaluate if a particular coin is fair or not. You have decided to use the following test: Accept that the coin is fair if in 30 tosses the coin gives between 11 and 19 heads (inclusive); reject the hypothesis of fairness otherwise. Compute the Type I error rate of this test. Interpret, in plain wor

    Selecting the appropriate alpha level

    Type I error is used in selecting the appropriate alpha level. Based on your understanding, why is Type I error more important than Type II error in selecting the appropriate alpha level?

    Type I and Type II Errors

    Given the following hypothesis test, what are the ramifications of a type I and type II error? Just reply in a sentence or two for each case. Forty perccent of overweight people have at least one symptom of disease X. A new diet plan purports to reduce the incidence of disease X symptoms in the overweight population. Using a

    Are Type I or Type II Errors More Concerning?

    Is it more important for the researcher to be concerned with Type I or Type II errors in a study? Why do these error types only apply to the analysis of data sets, rather than individual instances?

    Type I and Type II Errors of Null Hypotheses

    Given the following information, would your decision be to reject or fail to reject the null hypothesis? Setting the level of significance at .05 for decision making, please provide an explanation for your conclusion to help me understand the concepts. a) The null hypothesis that there is no relationship

    Type I error explanation for statistics students

    Metal detectors at airports are used to determine whether passengers are carrying weapons. If the null hypothesis states that a passenger isn't carrying a weapon, a type I error would occur whenever A) a weapon-free passenger passes the detector without activating the alarm. B) a weapon-free passenger passes the detector and

    Confidence interal, standard error, Cohen's d, Type II

    8.4. What are the five steps to create a confidence interval for a z distribution? 8.6. What effect does increasing the sample size have on the standard error and the test statistic for every hypothesis test? 8.8. What does it mean to say the effect-size statistic, such as Cohen's d, neutralizes the influence of sample siz

    Probability Type I or Type II Error: Soft-Drink Machine Example

    A soft-drink machine at a steak house is regulated so that the amount of drink dispensed is approximately normally distributed with a population mean of 200 millilitres and a standard deviation of 15 millilitres. The new machine is checked periodically by taking a sample of 9 drinks and computing the average content. If xÌ… fall

    Power and type 2 error

    Explain whether the following statements are correct. A type II error is the error of rejecting the null hypotheis when it is true. The type II error is denoted by (1-beta). Therefore the statistical power is the compliment of the risk of type II error. Factors that increase statistical power also decrease the risk of a t

    Type 1 and 2 errors: Southern children

    A researcher collects data on children's weights from a random sample of children in the South and concludes that children in the South weigh less than the national average. The researcher, however, does not realize that the sample includes many children who are small for their age and that in reality, there is no difference in

    Correctness of a study: significant consequences if negative

    In terms of correctness of a study, I agree type one errors can be very important. With Type II errors there are more negative consequences if the result is wrong but assumed to be correct. Do you think that there would be significant consequences if the study were to be correct but assumed to be negative?