Exam 17: Hypothesis Testing: Basic Concepts and Tests of Association

The higher the significance level used for testing a hypothesis, the higher is the probability of rejecting the null hypothesis when it is true.

The larger the degrees of freedom, the lower is the likelihood of observing differences among the variables.

A p-value of .45 means that the evidence against the null hypothesis is very weak.

For data in the previous question, what would the overall chi-square value be for the whole table if the expected value for the Q1 yes - Q2 yes cell was equal to 23 ?

The p-value is closest to

The confidence with which we may reject/accept a hypothesis is independent of the sample size, but dependent on the true population variance.

The Chi square test can provide a useful measurement of association.

A p-value of .07 means that the results are statistically significant at the 0.05 level. Assume that a new product is placed in a sample of stores.The sample mean for units sold is 35 units.We test the hypothesis that the population mean is only 20.

We can be more confident in rejecting the null hypothesis with a p-value of 0.05 than with a p-value of 0.02.

New Products Incorporated ran a test market for their latest product in two markets, City A and City B.Both have equal populations.The average weekly sales were $1,000 and $800, respectively, in the two cities.Based on this information, we can say that 1-sales in City A are significantly higher than sales in City B. 2-the difference in the sales level could be due to a sampling error. 3-the difference in the sales level may be due to the fact that the residents of City B accepted the product to a lesser degree than those of City A.

a If $\mu$ _x = 10, n = 16 σ _x² = 10, n = 16 The p-value for a sample observation of X = 11, based on the null hypothesis that the sample was drawn from the above population, would be closest to

Use the following information for questions -1-The marginal distribution for F is .2 often), .5 occasional), .3 seldom). 2-The marginal distribution for F is .5 often), .5 occasional), 0.0 seldom). 3-The marginal distribution for L is .5 convenient), .5 not convenient). 4-The marginal distribution for L is .2 convenient), .8 not convenient).

Use the following information for questions -According to the data above, which of the following is true? 1-E convenient, often) = E often, convenient) 2-E seldom, not convenient) = 30 3-E seldom, not convenient) = 20 4-E convenient, occasional) = 50

Hypothesis testing can be used to establish whether the null hypothesis is true or false.

The null hypothesis associated with the sample Chi square statistic is that the two intervally scaled.variables are statistically independent.

The Chi square test cannot be used to ascertain whether the observed pattern fits with the expected pattern.

After analyzing repeat purchase sales data from two market segments, the researcher reported that the p-value was 0.15.This implies that there are more than 15 chances out of 100 that the difference found was simply due to a sampling accident.

Use the following information for questions A subscription service stated that preferences for different national magazines were independent of geographical location.A survey was taken in which 300 respondents randomly chosen from three areas were given a choice among three different magazines.Each person expressed his or her favorite.The following results were obtained: -Suppose the chi-square value for the above test is 15; this will yield a significance level closest to the value

Use the following information for questions -For the data above, which of the following statements is true? 1-The $\chi$ ² statistic is 4.167. 2-The $\chi$ ² statistic is 6.25. 3-The p-value is less than 0.01.

Degrees of freedom refers to the number or bits of "free" or unconstrained data used in calculating a sample statistic.