Skip to main content
Cross Validated

Questions tagged [measurement]

Ask Question

Measurement is the assignment of a value (numeric or otherwise) to an observation.

365 questions
Newest Active Bountied Unanswered
Filter by
Sorted by
Tagged with
2 votes
1 answer
101 views

Suppose I have two metrics, x and y. I have measures for a few dozen units on both metrics, at time 1 and at time 2. I want to validate metric y, so that future users can use it as a substitute for ...
Clara's user avatar
  • 123
9 votes
3 answers
391 views

I’d like to ask a general question about metrics. Recently, while working as an intern, I was asked to evaluate the success of different marketing journeys (in a CRM/Marketing Cloud context). The data ...
magicdatabase's user avatar
  • 99
3 votes
1 answer
117 views

Many fields use questionnaires that ask questions with ordered answer options. For instance, a question might be I have a good self-esteem, with response options ranging from Fully disagree; Disagree; ...
Charly Marie's user avatar
  • 160
2 votes
2 answers
200 views

I have to analyse the results of an intervention research where 3 dependent variables were measured with questionnaires. Participiants were randomly assigned to intervention and control groups. In the ...
Marton Kovacs's user avatar
  • 23
15 votes
6 answers
3k views

For example, I often work with ages, for adults and infants. For adults, 0.001 years is less than a day. Rarely do we need to know adults' ages down to the hour. But, often databases store ages down ...
Æzor Æhai -him-'s user avatar
  • 269
1 vote
1 answer
76 views

Suppose that a population is comprehensively divided into mutually exclusive categories $1,...,n$. The proportion of the population in category $k$ is $p_k$, so that $p_1+\cdots+p_n=1$. The proposed ...
John Bentin's user avatar
  • 225
9 votes
3 answers
1k views

So far, it's always been my understanding that nominal data was a type of categorical data, not a synonym of it. For me, categorical data included ordinal data, not just nominal data. As of November ...
J-J-J's user avatar
  • 6,942
2 votes
0 answers
54 views

In Michael Eysenck's fundamentals of psychology, it says Another factor to consider when deciding which statistical test to use is the type of data you have obtained. There are four types of data of ...
Tim's user avatar
  • 20.1k
2 votes
1 answer
110 views

Christmas will be here before we know it, so we've started honing our christmas cookie baking skills. Today it was a madeleine variety, so almonds were involved. While weighing up the almonds the ...
AkselA's user avatar
  • 477
0 votes
0 answers
46 views

I have a distribution of a Groundtruth (green graph) that I would like to learn using xgboost. The red graph in the figure below shows the distribution of xgboost's learned predictions. By the way, ...
Jose_Peeterson's user avatar
  • 304
0 votes
0 answers
82 views

I've seen a few threads discussing something similar but I feel like my use case is a little different and doesn't fit the answers given. I have records for digital usage where a user can use the web ...
mateoc15's user avatar
  • 101
4 votes
1 answer
204 views

Scales of measurement often discussed as: Nominal: Qualitative category with no order Ordinal: Order but no meaningful distance between values Interval: Order and meaningful distance between values ...
Vefeagins's user avatar
  • 1,106
8 votes
1 answer
465 views

Multiple resources describing Item Response Theory (IRT) and comparing it to Classical Test Theory (CTT) note that CTT depends on a representative sample whereas IRT does not. Sample-independence of ...
JElder's user avatar
  • 1,464
9 votes
1 answer
173 views

We have been teaching sample size calculation for the comparison of two groups A and B. I was asked to provide a mathematical explanation of why it reduces power to "dichotomize" a ...
Mkanders's user avatar
  • 476
1 vote
2 answers
283 views

The problem is this: I want to "estimate the error made when attempting to predict the true score from the observed score when I am using an unreliable measurement" (Theory of Mental Tests, ...
Experience111's user avatar
  • 161
1 vote
1 answer
74 views

An interesting question came across my desk. With some hypothesized success rate, $p$, what is the minimum number of binomial trials needed to effectively measure this effect? Given an infinite number ...
jbuddy_13's user avatar
  • 3,970
2 votes
1 answer
71 views

I'm perplexed by this statement in Wikipedia article, 'Consilience': "Statistically, if three different tests are each 90% reliable when they give a positive result, a positive result from all ...
Jon Bragdon's user avatar
  • 23
0 votes
1 answer
85 views

I want to run a multi-group longitudinal model. Based on prior invariance testing, I can assume scalar invariance across groups and time. So is it appropriate to have both the same intercepts across ...
JoMo's user avatar
  • 1
3 votes
1 answer
174 views

I have two sets of measurements (two different methods), A and B. Correlation between the measurements is only modest. Therefore, I wondered whether there is some inherent bias in (one or both) of ...
pishcotec_a's user avatar
  • 41
3 votes
1 answer
107 views

Reliability is given by: $r_{xx} = \frac{Var(T)}{Var(X)}$ where $T$ is the true score and $X$ is the total score. Why isn't reliability simply: $r_{xx} = \frac{T}{X}$ where $T$ would be a sum of all ...
J. Doe's user avatar
  • 609
3 votes
0 answers
69 views

I am working on a dataset that has dry skull measurements from a museum's collection (twice as many samples) or a live specimen (less common). As you can imagine, the live specimen are on average a ...
KellyForrester's user avatar
  • 31
5 votes
2 answers
629 views

In exercise testing (spiroergometry), participants' oxygen uptake is measured continuously while they engange in physical exercise that progressively intensifies. The measurements are taken at regular ...
COOLSerdash's user avatar
  • 32.1k
1 vote
0 answers
146 views

I am a newbie here. I searched through the forum but did not find similar questions, so I hope someone who is proficient with SEM / lavaan can help out. I am using R lavaan and semTools to perform ...
zstats's user avatar
  • 11
2 votes
2 answers
110 views

I am comparing the distributions for the strength of two part designs. The test equipment maxes out at 300 units. The 300 units is an arbitrary limit of the equipment and does not represent a ...
AlexR's user avatar
  • 21
1 vote
1 answer
118 views

I have completed a measurement invariance analysis comparing high-school aged boys to high-school aged girls on a measure of depression. The results suggest that scores are not (scalar) invariant; ...
ila's user avatar
  • 203
0 votes
1 answer
86 views

I have this Venn chart that represent a dataset prediction of Identifying if our products are classified as "A41" standard or not The Blue Circle represents a Machine Learning Model ...
asmgx's user avatar
  • 311
4 votes
2 answers
422 views

The MAPE could be employed in the context of regression problem and is defined by $$ MAPE := \frac{1}{n} \sum_{t=1}^{n} \left| \frac{y_{t} - \hat{y}_{t}}{y_{t}} \right| $$ where $y_{t}$ is target ...
Ryu Dae Sick's user avatar
  • 95
3 votes
1 answer
112 views

I established scalar measurement invariance for a two-group CFA. The output from my final model showed that the latent mean in group 1 is lower than the latent mean in group 2. Can this difference in ...
user321797's user avatar
  • 125
3 votes
3 answers
237 views

The three major criteria for the quality of a measurement instrument are validity, reliability, and responsiveness. I understand validity and reliability, but I have trouble understanding the need to ...
Enuff's user avatar
  • 131
4 votes
2 answers
124 views

Suppose a gun is fired at the bullseye of a target a specific number of times. Ignoring the accuracy (e.g. all the shots are well to the left and above the bullseye), is there a standard way of ...
Ray Butterworth's user avatar
  • 269
7 votes
3 answers
2k views

My dataset includes "decade founded" but not "year founded" for organizations. I need to include some "maturity" variable in the model. Decade is the best I have. The ...
user398893's user avatar
  • 71
6 votes
1 answer
642 views

I have a series of data points representing the number of OKs for a test. For each data point, I want to calculate by how much its value changed compared to the preceding value, and I need this ...
Mr Kartofel's user avatar
  • 61
2 votes
2 answers
196 views

I work in a health service and have a PhD student who was told by my boss (her primary supervisor) to measure clinicians' responses concerning what proportion of their clients had a certain condition ...
llewmills's user avatar
  • 2,345
0 votes
1 answer
60 views

I have a question about using ratios as variables in alpine ski racing research. We want to compare skiers' performance on different days, but snow conditions affect the results. To address this, we ...
Cmagelssen's user avatar
  • 59
2 votes
0 answers
63 views

Noob question. I have a full population of every inspector rating for all items being rated. Each inspector has inspected a subset of the items and given them a rating, but different inspectors have ...
inspecting_inspectors's user avatar
  • 21
0 votes
0 answers
55 views

I have a formula and I am not sure how the author of this paper got to that formula. Im working on an algorithm that can filter out ground points from a Point cloud. The author describes the following ...
Okan's user avatar
  • 1
7 votes
1 answer
456 views

I am currently working on the analysis of measurement data and have the problem of obvious non-normal data. Since most methods I want to use require normality (especially statistical process control ...
Krautsultan's user avatar
  • 167
0 votes
1 answer
244 views

I have a psychological test that consist of a set of binary items. It has a noticeable ceiling effect in the sum scores (essentially, a majority of participants get most items correct). I also see ...
FredrikH-R's user avatar
  • 275
3 votes
1 answer
184 views

If BMI is calculated from measures of patient height as well has weight, do statistical tests and resulting p values around BMI changes need adjusting for multiple comparisons? I.e. Two tests were ...
holmes's user avatar
  • 101
0 votes
0 answers
309 views

Say you have measured three conditions (x, y, and z) together and at three separate times (three replicates). These raw values are normally distributed and in a linear space. You use those three ...
JebidiahSpringfield's user avatar
  • 1
13 votes
1 answer
686 views

Is there a good expository account that explains and justifies Stevens's classification of "levels of measurement" into nominal, ordinal, interval, and ratio, that is comprehensible to all ...
Michael Hardy's user avatar
  • 13.1k
5 votes
1 answer
146 views

Assume that we want to compare the agreement of two methods of measuring blood pressure (e.g. a machine and a sphygmomanometer). In their paper, Preiss & Fisher (2008) discuss the standard ...
COOLSerdash's user avatar
  • 32.1k
0 votes
0 answers
34 views

Suppose I have a quantity that is measured periodically, that is continuous in the following sense: In order for the quantity x to move from x=a to x=b, x must pass through all the values between a ...
andrewH's user avatar
  • 3,297
0 votes
0 answers
84 views

I need your help with a problem that I noticed and I don't know the solution (I am not from statistics). In sum, I would like to create a measurement instrument that is adaptive in that respondents ...
Larissa Becker's user avatar
  • 1
0 votes
0 answers
51 views

I'm doing a cross-lagged panel modeling for three time points. For one specific construct of interest, I have three items that were used for across three time points, but the number of items used for ...
hakim's user avatar
  • 13
3 votes
2 answers
689 views

I am trying to establish measurement invariance between two groups on a depression measure: high-school aged boys and high-school aged girls. Though my entire sample reports elevated depression ...
ila's user avatar
  • 203
1 vote
0 answers
77 views

I am supposed the investigate viscosity related phenomena in water flow through a horizontal pipe, connected to a water tank at one end, and with clear opening on the other. Mounted in the middle is ...
This-name-will-do-nicely's user avatar
  • 11
1 vote
0 answers
55 views

Assume that a device is traveling at a constant expected speed $\mu$, subject to random variation with standard deviation $\sigma$, for a measurement period of duration $t$. Then the expected travel ...
shadowtalker's user avatar
  • 13k
1 vote
1 answer
1k views

TLDR: I need to determine the minimum sample size for measuring the energy consumption of code. Hello, I'm trying to determine how many samples (N) I need in an experiment to be confident that my ...
Jamie Baldwin Pedersen's user avatar
  • 11
1 vote
0 answers
39 views

I have measured one parameter with two identical devices. Unfortunately one device shows higher values on average. Also maximum and minimum of the values differ by exactly the same value like the ...
Lara's user avatar
  • 11

1
2 3 4 5
…
8