Observations that are measured at successive points in time is what type of data ANS Time series data Observations that are measured at the same time represent what type of data ANS Cross sectional data Observations estimates of the slope and y intercept are respectively 2 5 and 5 0 The least squares Of the last 500 customers entering a supermarket 50 have purchased a wireless phone If the relative frequency approach for assigning probabilities is used the probability that the next customer will purchase a wireless phone is 10 On the average 1 6 customers per minute arrive at any one of the checkout counters of Meijer grocery store What type of probability distribution can be used to find out the probability that there will be no customers arriving at a checkout counter in 10 minutes Poisson distribution Most values of a standard normal distribution lie between 3 and 3 In a Poisson distribution the mean equals the variance In a Poisson distribution the mean equals the variance In a positively skewed distribution the median is less than the mean In a histogram the proportion of the total area which must be to the right of the mean is Exactly 50 if the distrbution is symmetric and unimodal In a negatively skewed distribution which of the following is the correct statement the distance from the smallest observation is larger than the distance from Q3 to the largest observation In a histogram the proportion of the total area which must be to the left of the median is EXACTLY 50 In a simple linear regression problem the following sum of squares are produced In a perfectly symmetric distribution which of the following statements is false The distance from Q1 to Q3 is half the distance from the smallest to the largest observation In a positively skewed distribution which of the following is the correct statement The distance from Q1 to Q2 is smaller than the distance from Q2 to Q3 In a hypothesis test for the population variance the hypotheses are H0 2 30 vs H1 2 30 If the sample size is 20 and the test is being carried out at the 5 level of significance the null hypothesis is rejected if 2 10 117 In a hypothesis test for the population variance the hypotheses are H0 2 100 vs H1 2 100 If the sample size is 15 and the test is being carried out at the 10 level of significance the rejection region is 2 6 571 or 2 23 685 In a one tail test the p value is found to be equal to 0 068 If the test had been two tail the p value would have been 0 136 In a two tail test for the population mean the null hypothesis will be rejected at level of significance if the value of the standardized test statistic z is such that z z 2 In a two tail test for the population mean if the null hypothesis is rejected when the alternative hypothesis is true a correct decision is made In a regression problem the following pairs of x y are given 3 1 3 1 3 0 3 2 and 3 2 That indicates that the either a or b since they are identical In a simple linear regression problem r and b0 must have the same sign In a criminal trial a Type I error is made when an innocent person is convicted In a criminal trial a Type II error is made when a guilty defendant is acquitted In constructing a confidence interval estimate for the difference between the means of two independent normally distributed populations we pool the sample variances when the unknown population variances are equal In constructing a confidence interval estimate for the difference between two population proportions we never pool the population proportions In developing an interval estimate for a population mean the population standard deviation was assumed to be 10 The interval estimate was 50 92 2 14 Had equaled 20 the interval estimate would be50 92 4 28 In its standardized form the normal distribution has a mean of 0 and a standard deviation of 1 In order to predict with 80 confidence the expected value of y for a given value of x in a simple linear regression problem a random sample of 15 observations is taken Which of the following t table values listed below would be used 1 350 In order to predict with 98 confidence the expected value of y for a given value of x in a simple linear regression problem a random sample of 15 observations is taken Which of the following t table values listed below would be used 2 650 In order to estimate with 95 confidence the expected value of y for a given value of x in a simple linear regression problem a random sample of 10 observations is taken Which of the following t table values listed below would be used 2 306 In order to predict with 90 confidence the expected value of y for a given value of x in a simple linear regression problem a random sample of 10 observations is taken Which of the following t table values listed below would be used 1 860 In order to draw a scatter diagram we need interval data for TWO VARIABLES In regression analysis the residuals represent the difference between the actual and their predicted values y values In regression analysis if the coefficient of determination is 1 0 then the sum of squares for error must be 0 0 In selecting the sample size to estimate the population proportion p if we have no knowledge of even the approximate values of the sample proportion we let 0 50 In the notation below X is the random variable c is a constant and V refers to the variance Which of the following laws of variance is not true V X c V X c In the simple linear regression model the y intercept represents the value of y when x 0 In the first order linear regression model the population parameters of the y intercept and the slope are estimated respectively by b0 and b 1 In the simple linear regression model the slope represents the average change in unit change in x y per In the first order linear regression model the population parameters of the y intercept and the slope are respectively 0 and 1 In the least squares regression line x 1 0In testing for differences between the means of two independent populations the null the predicted value of y equals 1 0 when hypothesis is In the following cross classification table how are gender and pet ownership related The percentage of pet owners is the same for females and males Own a pet Don t own a pet Females Males 60 80 30 40 In testing the hypotheses H0 50 vs H1 50 the following information is known n 64 53 5 and 10 The standardized test statistic z equals 2 80 In testing the hypotheses H0 75 vs H1 75 if the value of the test statistic z …