# Statistics Homework Help

Filter Questions
• Statistics
The reason we use moving averages in the first place is that a lot of time-series data is noisy; due to errors in data collection or random fluctuations in the real-world phenomenon, the data jumps...

Asked by cfoster4 on via web

• Statistics
Let's consider each statement in turn. "It is good practice to include a measure of expected forecast error with any forecast."That one is clearly true. You always want to include error measures in...

Asked by cfoster4 on via web

• Math
The one-way analysis of variance allows us to compare the values of parameters (often means) between groups. The assumptions to perform an ANOVA test are that the samples are taken from normal...

Asked by keishashae on via web

• Social Sciences
i) One group pre-test/post-test design Here, the experiment is carried out on only one group. The main advantage to having one group is that variability between individuals' results in the...

Asked by lskohleffel on via web

• Statistics
The analysis of statistics may possibly be considered art--"the expression or application of human creative skill and imagination"--since it can sometimes involve a creative manipulation of...

Asked by babylon on via web

• Math
30 cards are selected from a deck 1) without replacement 2) with replacement. We wish to know the chance of getting at least one ace. 1) Each time we select a card, it is either an ace or not. The...

Asked by flkdajflsak on via web

• Statistics
A U.S. travel center survey report states that Americans stayed an average of 7.5 nights when they went on vacation. The sample size is 1500. The point estimate of the population mean is the...

Asked by lwilli on via web

• Math
Using the fact the expected value operator E(X) is linear we have that `E[g(X) ] = g(E[X])` if `g(x)` is a linear function. In this case we are given that `g(x) = a` so that `E[g(X)] = g(E[X]) =...

Asked by user2537997 on via web

• Math
` `Out of the first 30 pilot samples of `n=100` items per population/batch tested for nonconformity, 95 out of the 30 x 100 = 3000 items were found to be defective. From these pilot data then, the...

Asked by lazy34 on via web

• Math
We have that the random variable `X` is such that `X ~`~ Pois(`lambda`) where the mean is given by `lambda=5` . We would like to know the expected value of the random variable `Y = 2^X` Using the...

Asked by leevicboy on via web

• Math
The confidence intervals given will be of the form `hat(p) pm z_(1-alpha/2)sqrt((hat(p)(1-hat(p)))/n)` where `z_(1-alpha/2)` is the 100(alpha/2)th percentile of the standard Normal distribution....

Asked by nightpast on via web

• Math
The "heures de vie" or "lifetime in hours" of bulb 10 is, from the table 12 hours. Consider the lifetimes in hours `x_i` `(i = 1,2,...,20)` of the other bulbs 1-20 (excepting bulb 10). The average...

Asked by misztibabe on via web

• Statistics
In all of these cases, we are doing some sort of test. We are asking a yes or no question and trying to answer it with our test. In Option 1, we ask if Mary is pregnant. In Option 2, we ask if...

Asked by newspapers on via web

• Math
There are data for each of the three seasons so we should include this in the frequency table and histogram to give all the information. i) A frequency table is a table giving the number of...

Asked by jaysen12 on via web

• Math
If you wish to carry out a linear regression then create a new variable `x_1 = sin(x-pi)` and carry out the regression of `y` on `x_1` in the usual way, ie fit `y = alpha + betax_1` using...

Asked by laurfree on via web

• Math
We have the paired fuel consumptions (in miles/gal) for each car: city 18 22 21 21 highway 26 31 29 29 It is well known that fuel consumption in the city is worse...

Asked by disaza on via web

• Math
Given the critical values for 96th and 97th percentiles `Phi^(-1)(0.96) = z_(0.96) = 1.751` and `Phi^(-1)(0.97) = z_(0.97) = 1.881` use 'linear interpolation' to find the 96.4th percentile...

Asked by bparvi on via web

• Social Sciences
When you are looking balance, such as in a statistical graph, and you are looking at symetrical balance you are looking at a graph that has a even number of people before and after the mean. This...

Asked by kellerkay on via web

• Social Sciences
When you are designing a research experiment you want to first have your research question and your research hypothesis. What do you expect to find when you are looking at subjects managing...

Asked by lcowan6 on via web

• Math
The sample taken is a simple random sample (srs) so is representative of the population as a whole. If 1139 out of the 1201 Americans sampled were found to live in neighborhoods with acceptable...

Asked by akenneh on via web

• Math
A) A large sample size is necessary in order to apply the Central Limit Theorem and assume Normality. B) The mean of the ages the individuals would like to live was found to be 87.9 and the...

Asked by akenneh on via web

• Math
Denote the observations `x_i`, `i = 1,2,3,...,10` Then the mean `bar(x)` is given by `bar(x) = sum_1^10 x_i/10 = 70.5` and the standard deviation is given by `sd(x) = sqrt(V(x)) = sqrt(sum_1^10...

Asked by endripl on via web

• Math
Denote the (binary - value 0 or 1) observations from the two populations `x_i` , `i=1,2,...,n_x` and `y_j`, `j=1,2,...,n_y` where `n_x = 280` and `n_y =350`. We are given that `sum_i x_i = 132`...

Asked by drying on via web

• Social Sciences
The NIBRS is based on the collection of data from the records management systems of federal, state and local law enforcement agencies. The incidents and arrests that are included into the national...

Asked by kisstopher603 on via web

• Health
Health data can be divide into two types: retrospectively and prospectively collected. Retrospective/historical studies are sometimes referred to as observational studies. However, some...

Asked by gracedaymon on via web

• Statistics
The question has been edited as you can ask only one question at a time. To determine the mean from the given frequency table first determine the mid point of each interval. interval...

Asked by stargsd5 on via web

• Statistics
Validity refers to the point up to which the test that is being taken is actually testing and measuring what is supposed to. There is no specific definition other than this, considering that the...

Asked by shewa55 on via web

• Public Health
A result in data analysis is said to be statistically significant if we are 95% confident, say, that the effect we have observed through analysis is a real one and not one that is manifested by...

Asked by chrisns on via web

• Statistics
A person makes a Type I error when they rejected a null hypothesis that could possibly be true. In this case, the politician is saying that he will certainly win the election. Of course, he is...

Asked by stargsd5 on via web

• Public Health
When testing a hypothesis it is very important to be clear about what measure is actually of interest and what target population it applies to. Often when we collect data we cannot get directly at...

Asked by chrisns on via web

• Statistics
The most likely answer is that this data would be nominal. Depending on how the political scientist was gathering the data, it could conceivably be ordinal or even interval. But this is much less...

Asked by stargsd5 on via web

• Statistics
When you are talking about type 1 errors you are looking at a statistical term that means that after running a statistical analysis you have rejected a null hypothesis (the hypothesis that states...

Asked by hakkie on via web

• Statistics
Correlational data cannot tell us that causation has occurred. We should also note, though, that correlation does not mean that causation has notoccurred. All that correlation can tell us is that...

Asked by djmckay on via web

• Statistics
The reason for this is that statistics can easily be manipulated to tell a story that a particular source wants them to tell. Therefore, you need to have evidence from a source that is not trying...

Asked by brent6969 on via web

• Math
First add the total minutes tardy upfor the whole week for each of the faculty positions. mins tardy pay per min (Rs.) cost per week (Rs.) Lecturers 91...

Asked by studentdiversified on via web

• Statistics
A concept is simply an idea. It is something that is fairly vague and it can be difficult to understand how to measure the concept. A variable is much more specific and concrete. It is a...

Asked by rhazward on via web