Expected value
The table below shows how to construct F ratios when an experiment uses a Random-effects model.
Table 2. Random-Effects Model
Effect | Mean square: Expected value | F ratio |
---|---|---|
A | σ + nσ + nqσ | |
B | σ + nσ + npσ | |
AB | σ + nσ | |
Error | σ |
The table below shows how to construct F ratios when an experiment uses a mixed model. Here, Factor A is a fixed effect, and Factor B is a random effect.
Table 3. Mixed Model
Effect | Mean square: Expected value | F ratio |
---|---|---|
A (fixed) | σ + nσ + nqσ | |
B (random) | σ + npσ | |
AB | σ + nσ | |
Error | σ |
For each F ratio in the tables above, notice that numerator should equal the denominator when the variation due to the source effect ( σ 2 SOURCE ) is zero (i.e., when the source does not affect the dependent variable). And the numerator should be bigger than the denominator when the variation due to the source effect is not zero (i.e., when the source does affect the dependent variable).
Defined in this way, each F ratio is a convenient measure that we can use to test the null hypothesis about the effect of a source (Factor A, Factor B, or the AB interaction) on the dependent variable. Here's how to conduct the test:
What does it mean for the F ratio to be significantly greater than one? To answer that question, we need to talk about the P-value.
In an experiment, a P-value is the probability of obtaining a result more extreme than the observed experimental outcome, assuming the null hypothesis is true.
With analysis of variance for a full factorial experiment, the F ratios are the observed experimental outcomes that we are interested in. So, the P-value would be the probability that an F ratio would be more extreme (i.e., bigger) than the actual F ratio computed from experimental data.
How does an experimenter attach a probability to an observed F ratio? Luckily, the F ratio is a random variable that has an F distribution . The degrees of freedom (v 1 and v 2 ) for the F ratio are the degrees of freedom associated with the effects used to compute the F ratio.
For example, consider the F ratio for Factor A when Factor A is a fixed effect. That F ratio (F A ) is computed from the following formula:
F A = F(v 1 , v 2 ) = MS A / MS WG
MS A (the numerator in the formula) has degrees of freedom equal to df A ; so for F A , v 1 is equal to df A . Similarly, MS WG (the denominator in the formula) has degrees of freedom equal to df WG ; so for F A , v 2 is equal to df WG . Knowing the F ratio and its degrees of freedom, we can use an F table or an online calculator to find the probability that an F ratio will be bigger than the actual F ratio observed in the experiment.
To find the P-value associated with an F ratio, use Stat Trek's free F distribution calculator . You can access the calculator by clicking a link in the table of contents (at the top of this web page in the left column). find the calculator in the Appendix section of the table of contents, which can be accessed by tapping the "Analysis of Variance: Table of Contents" button at the top of the page. Or you can click tap the button below.
For examples that show how to find the P-value for an F ratio, see Problem 1 or Problem 2 at the end of this lesson.
Recall that the experimenter specified a significance level early on - before the first data point was collected. Once you know the significance level and the P-values, the hypothesis tests are routine. Here's the decision rule for accepting or rejecting a null hypothesis:
A "big" P-value for a source of variation (Factor A, Factor B, or the AB interaction) indicates that the source did not have a statistically significant effect on the dependent variable. A "small" P-value indicates that the source did have a statistically significant effect on the dependent variable.
The hypothesis tests tell us whether sources of variation in our experiment had a statistically significant effect on the dependent variable, but the tests do not address the magnitude of the effect. Here's the issue:
With this in mind, it is customary to supplement analysis of variance with an appropriate measure of effect size. Eta squared (η 2 ) is one such measure. Eta squared is the proportion of variance in the dependent variable that is explained by a treatment effect. The eta squared formula for a main effect or an interaction effect is:
η 2 = SS EFFECT / SST
where SS EFFECT is the sum of squares for a particular treatment effect (i.e., Factor A, Factor B, or the AB interaction) and SST is the total sum of squares.
It is traditional to summarize ANOVA results in an analysis of variance table. Here, filled with hypothetical data, is an analysis of variance table for a 2 x 3 full factorial experiment.
Analysis of Variance Table
Source | SS | df | MS | F | P |
---|---|---|---|---|---|
A | 13,225 | p - 1 = 1 | 13,225 | 9.45 | 0.004 |
B | 2450 | q - 1 = 2 | 1225 | 0.88 | 0.427 |
AB | 9650 | (p-1)(q-1) = 2 | 4825 | 3.45 | 0.045 |
WG | 42,000 | pq(n - 1) = 30 | 1400 | ||
Total | 67,325 | npq - 1 = 35 |
In this experiment, Factors A and B were fixed effects; so F ratios were computed with that in mind. There were two levels of Factor A, so p equals two. And there were three levels of Factor B, so q equals three. And finally, each treatment group had six subjects, so n equal six. The table shows critical outputs for each main effect and for the AB interaction effect.
Many of the table entries are derived from the sum of squares (SS) and degrees of freedom (df), based on the following formulas:
MS A = SS A / df A = 13,225/1 = 13,225
MS B = SS B / df B = 2450/2 = 1225
MS AB = SS AB / df AB = 9650/2 = 4825
MS WG = MS WG / df WG = 42,000/30 = 1400
F A = MS A / MS WG = 13,225/1400 = 9.45
F B = MS B / MS WG = 2450/1400 = 0.88
F AB = MS AB / MS WG = 9650/1400 = 3.45
where MS A is mean square for Factor A, MS B is mean square for Factor B, MS AB is mean square for the AB interaction, MS WG is the within-groups mean square, F A is the F ratio for Factor A, F B is the F ratio for Factor B, and F AB is the F ratio for the AB interaction.
An ANOVA table provides all the information an experimenter needs to (1) test hypotheses and (2) assess the magnitude of treatment effects.
The P-value (shown in the last column of the ANOVA table) is the probability that an F statistic would be more extreme (bigger) than the F ratio shown in the table, assuming the null hypothesis is true. When a P-value for a main effect or an interaction effect is bigger than the significance level, we accept the null hypothesis for the effect; when it is smaller, we reject the null hypothesis.
For example, based on the F ratios in the table above, we can draw the following conclusions:
To assess the strength of a treatment effect, an experimenter can compute eta squared (η 2 ). The computation is easy, using sum of squares entries from an ANOVA table in the formula below:
where SS EFFECT is the sum of squares for the main or interaction effect being tested and SST is the total sum of squares.
To illustrate how to this works, let's compute η 2 for the main effects and the interaction effect in the ANOVA table below:
Source | SS | df | MS | F | P |
---|---|---|---|---|---|
A | 100 | 2 | 50 | 2.5 | 0.09 |
B | 180 | 3 | 60 | 3 | 0.04 |
AB | 300 | 6 | 50 | 2.5 | 0.03 |
WG | 960 | 48 | 20 | ||
Total | 1540 | 59 |
Based on the table entries, here are the computations for eta squared (η 2 ):
η 2 A = SSA / SST = 100 / 1540 = 0.065
η 2 B = SSB / SST = 180 / 1540 = 0.117
η 2 AB = SSAB / SST = 300 / 1540 = 0.195
Conclusion: In this experiment, Factor A accounted for 6.5% of the variance in the dependent variable; Factor B, 11.7% of the variance; and the interaction effect, 19.5% of the variance.
In the ANOVA table shown below, the P-value for Factor B is missing. Assuming Factors A and B are fixed effects , what is the correct entry for the missing P-value?
Source | SS | df | MS | F | P |
---|---|---|---|---|---|
A | 300 | 4 | 75 | 5.00 | 0.002 |
B | 100 | 2 | 50 | 3.33 | ??? |
AB | 200 | 8 | 25 | 1.67 | 0.12 |
WG | 900 | 60 | 15 | ||
Total | 1500 | 74 |
Hint: Stat Trek's F Distribution Calculator may be helpful.
(A) 0.01 (B) 0.04 (C) 0.20 (D) 0.97 (E) 0.99
The correct answer is (B).
A P-value is the probability of obtaining a result more extreme (bigger) than the observed F ratio, assuming the null hypothesis is true. From the ANOVA table, we know the following:
F B = F(v 1 , v 2 ) = MS B / MS WG
Therefore, the P-value we are looking for is the probability that an F with 2 and 60 degrees of freedom is greater than 3.33. We want to know:
P [ F(2, 60) > 3.33 ]
Now, we are ready to use the F Distribution Calculator . We enter the degrees of freedom (v1 = 2) for the Factor B mean square, the degrees of freedom (v2 = 60) for the within-groups mean square, and the F value (3.33) into the calculator; and hit the Calculate button.
The calculator reports that the probability that F is greater than 3.33 equals about 0.04. Hence, the correct P-value is 0.04.
In the ANOVA table shown below, the P-value for Factor B is missing. Assuming Factors A and B are random effects , what is the correct entry for the missing P-value?
Source | SS | df | MS | F | P |
---|---|---|---|---|---|
A | 300 | 4 | 75 | 3.00 | 0.09 |
B | 100 | 2 | 50 | 2.00 | ??? |
AB | 200 | 8 | 25 | 1.67 | 0.12 |
WG | 900 | 60 | 15 | ||
Total | 1500 | 74 |
(A) 0.01 (B) 0.04 (C) 0.20 (D) 0.80 (E) 0.96
The correct answer is (C).
F B = F(v 1 , v 2 ) = MS B / MS AB
Therefore, the P-value we are looking for is the probability that an F with 2 and 8 degrees of freedom is greater than 2.0. We want to know:
P [ F(2, 8) > 2.0 ]
Now, we are ready to use the F Distribution Calculator . We enter the degrees of freedom (v1 = 2) for the Factor B mean square, the degrees of freedom (v2 = 8) for the AB interaction mean square, and the F value (2.0) into the calculator; and hit the Calculate button.
The calculator reports that the probability that F is greater than 2.0 equals about 0.20. Hence, the correct P-value is 0.20.
Saul McLeod, PhD
Editor-in-Chief for Simply Psychology
BSc (Hons) Psychology, MRes, PhD, University of Manchester
Saul McLeod, PhD., is a qualified psychology teacher with over 18 years of experience in further and higher education. He has been published in peer-reviewed journals, including the Journal of Clinical Psychology.
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On This Page:
Experimental design refers to how participants are allocated to different groups in an experiment. Types of design include repeated measures, independent groups, and matched pairs designs.
Probably the most common way to design an experiment in psychology is to divide the participants into two groups, the experimental group and the control group, and then introduce a change to the experimental group, not the control group.
The researcher must decide how he/she will allocate their sample to the different experimental groups. For example, if there are 10 participants, will all 10 participants participate in both groups (e.g., repeated measures), or will the participants be split in half and take part in only one group each?
Three types of experimental designs are commonly used:
Independent measures design, also known as between-groups , is an experimental design where different participants are used in each condition of the independent variable. This means that each condition of the experiment includes a different group of participants.
This should be done by random allocation, ensuring that each participant has an equal chance of being assigned to one group.
Independent measures involve using two separate groups of participants, one in each condition. For example:
Repeated Measures design is an experimental design where the same participants participate in each independent variable condition. This means that each experiment condition includes the same group of participants.
Repeated Measures design is also known as within-groups or within-subjects design .
Suppose we used a repeated measures design in which all of the participants first learned words in “loud noise” and then learned them in “no noise.”
We expect the participants to learn better in “no noise” because of order effects, such as practice. However, a researcher can control for order effects using counterbalancing.
The sample would be split into two groups: experimental (A) and control (B). For example, group 1 does ‘A’ then ‘B,’ and group 2 does ‘B’ then ‘A.’ This is to eliminate order effects.
Although order effects occur for each participant, they balance each other out in the results because they occur equally in both groups.
A matched pairs design is an experimental design where pairs of participants are matched in terms of key variables, such as age or socioeconomic status. One member of each pair is then placed into the experimental group and the other member into the control group .
One member of each matched pair must be randomly assigned to the experimental group and the other to the control group.
Experimental design refers to how participants are allocated to an experiment’s different conditions (or IV levels). There are three types:
1. Independent measures / between-groups : Different participants are used in each condition of the independent variable.
2. Repeated measures /within groups : The same participants take part in each condition of the independent variable.
3. Matched pairs : Each condition uses different participants, but they are matched in terms of important characteristics, e.g., gender, age, intelligence, etc.
Read about each of the experiments below. For each experiment, identify (1) which experimental design was used; and (2) why the researcher might have used that design.
1 . To compare the effectiveness of two different types of therapy for depression, depressed patients were assigned to receive either cognitive therapy or behavior therapy for a 12-week period.
The researchers attempted to ensure that the patients in the two groups had similar severity of depressed symptoms by administering a standardized test of depression to each participant, then pairing them according to the severity of their symptoms.
2 . To assess the difference in reading comprehension between 7 and 9-year-olds, a researcher recruited each group from a local primary school. They were given the same passage of text to read and then asked a series of questions to assess their understanding.
3 . To assess the effectiveness of two different ways of teaching reading, a group of 5-year-olds was recruited from a primary school. Their level of reading ability was assessed, and then they were taught using scheme one for 20 weeks.
At the end of this period, their reading was reassessed, and a reading improvement score was calculated. They were then taught using scheme two for a further 20 weeks, and another reading improvement score for this period was calculated. The reading improvement scores for each child were then compared.
4 . To assess the effect of the organization on recall, a researcher randomly assigned student volunteers to two conditions.
Condition one attempted to recall a list of words that were organized into meaningful categories; condition two attempted to recall the same words, randomly grouped on the page.
Ecological validity.
The degree to which an investigation represents real-life experiences.
These are the ways that the experimenter can accidentally influence the participant through their appearance or behavior.
The clues in an experiment lead the participants to think they know what the researcher is looking for (e.g., the experimenter’s body language).
The variable the experimenter manipulates (i.e., changes) is assumed to have a direct effect on the dependent variable.
Variable the experimenter measures. This is the outcome (i.e., the result) of a study.
All variables which are not independent variables but could affect the results (DV) of the experiment. Extraneous variables should be controlled where possible.
Variable(s) that have affected the results (DV), apart from the IV. A confounding variable could be an extraneous variable that has not been controlled.
Randomly allocating participants to independent variable conditions means that all participants should have an equal chance of taking part in each condition.
The principle of random allocation is to avoid bias in how the experiment is carried out and limit the effects of participant variables.
Changes in participants’ performance due to their repeating the same or similar test more than once. Examples of order effects include:
(i) practice effect: an improvement in performance on a task due to repetition, for example, because of familiarity with the task;
(ii) fatigue effect: a decrease in performance of a task due to repetition, for example, because of boredom or tiredness.
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Factorial experiments of soil conditioning for earth pressure balance shield tunnelling in water-rich gravel sand and conditioning effects’ prediction based on particle swarm optimization–relevance vector machine algorithm.
2. tunnel overview and engineering geology, 3. laboratory tests on soil conditioning, 3.1. factorial experimental design, 3.2. analysis of test results, 3.3. normalized effect analysis, 3.4. main effect analysis, 3.5. interaction analysis, 3.6. equivalence relationship prediction, 4. soil conditioning prediction based on pso–rvm, 4.1. pso–rvm algorithm, 4.2. case study, 5. field application, 6. conclusions, author contributions, data availability statement, conflicts of interest.
Click here to enlarge figure
A | A | A | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
B | B | B | B | B | B | B | B | B | B | B | B | B | B | B | |
C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C |
C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C |
C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C |
C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C |
C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C | A B C |
Data Source | Degree of Freedom | Adjusted Sum of Squares | Adjusted Mean Squares | T-Value | F-Value | p-Value |
---|---|---|---|---|---|---|
A | 2 | 60,784 | 30,391.8 | −178.69 | 37,947.47 | 0.0011 |
B | 4 | 37,638 | 9409.5 | −139.66 | 11,748.75 | 0.0013 |
C | 4 | 26,362 | 6590.5 | −110.60 | 8229.01 | 0.0041 |
A × B | 8 | 18,060 | 2257.5 | 102.17 | 2818.77 | 0.0062 |
A × C | 8 | 6833 | 854.2 | 61.44 | 1066.52 | 0.0068 |
B × C | 16 | 2766 | 172.9 | 31.16 | 215.83 | 0.0071 |
A × B × C | 32 | 3070 | 95.9 | −7.45 | 119.80 | 0.0077 |
Sample Number | Input Variables | Output Variables | |||||
---|---|---|---|---|---|---|---|
c (%) | c (%) | c (%) | Permeability Coefficient (Before Conditioning) (×10 m/s) | Resistivity of Sand (Ω·m) | Slump Value (mm) | Permeability Coefficient (After Conditioning) (×10 m/s) | |
1 | 25 | 5 | 14 | 8.98 | 54.24 | 121 | 4.08 |
2 | 50 | 4 | 10 | 8.90 | 54.10 | 143 | 9.88 |
3 | 75 | 2 | 14 | 9.12 | 56.44 | 55 | 0.41 |
4 | 50 | 4 | 6 | 9.05 | 53.63 | 168 | 21.88 |
5 | 75 | 3 | 10 | 9.09 | 54.68 | 51 | 0.21 |
6 | 25 | 2 | 10 | 9.25 | 56.67 | 192 | 58.82 |
7 | 50 | 3 | 6 | 8.70 | 53.13 | 187 | 45.11 |
8 | 75 | 5 | 10 | 8.95 | 55.89 | 57 | 0.49 |
9 | 25 | 1 | 8 | 8.89 | 54.94 | 205 | 73.53 |
10 | 50 | 3 | 12 | 8.98 | 55.37 | 124 | 4.73 |
11 | 75 | 4 | 10 | 9.13 | 51.58 | 50 | 0.14 |
12 | 25 | 5 | 6 | 9.11 | 55.23 | 180 | 28.59 |
13 | 50 | 3 | 8 | 9.14 | 56.49 | 176 | 26.33 |
14 | 25 | 3 | 8 | 8.96 | 51.42 | 186 | 40.85 |
15 | 50 | 2 | 10 | 9.24 | 53.44 | 162 | 16.24 |
16 | 25 | 1 | 12 | 9.13 | 53.44 | 195 | 62.09 |
17 | 50 | 2 | 8 | 8.87 | 56.40 | 181 | 31.76 |
18 | 25 | 2 | 14 | 9.27 | 53.18 | 182 | 32.68 |
19 | 75 | 3 | 8 | 9.22 | 55.54 | 117 | 3.04 |
20 | 25 | 5 | 10 | 8.80 | 55.99 | 148 | 11.29 |
21 | 50 | 1 | 8 | 8.59 | 52.25 | 184 | 35.29 |
22 | 75 | 2 | 6 | 8.83 | 51.83 | 159 | 14.12 |
23 | 50 | 4 | 14 | 8.79 | 53.74 | 113 | 2.82 |
24 | 75 | 1 | 12 | 8.94 | 53.50 | 118 | 3.27 |
25 | 50 | 5 | 10 | 9.04 | 54.93 | 100 | 1.41 |
26 | 75 | 3 | 14 | 9.09 | 54.15 | 33 | 0.02 |
27 | 25 | 3 | 14 | 8.73 | 54.54 | 140 | 8.17 |
28 | 25 | 2 | 8 | 9.15 | 54.80 | 193 | 61.27 |
29 | 50 | 1 | 6 | 9.23 | 55.28 | 196 | 64.94 |
30 | 75 | 5 | 14 | 8.62 | 54.98 | 46 | 0.08 |
31 | 25 | 3 | 12 | 8.71 | 53.06 | 159 | 14.12 |
32 | 75 | 3 | 12 | 8.69 | 55.85 | 41 | 0.07 |
33 | 50 | 3 | 14 | 8.95 | 56.57 | 124 | 4.24 |
34 | 25 | 4 | 6 | 9.09 | 55.14 | 183 | 33.18 |
35 | 50 | 4 | 8 | 8.99 | 56.66 | 160 | 14.26 |
36 | 75 | 1 | 8 | 9.13 | 56.15 | 140 | 8.17 |
37 | 25 | 5 | 8 | 8.91 | 54.14 | 169 | 22.88 |
38 | 75 | 1 | 6 | 8.96 | 52.54 | 161 | 15.53 |
39 | 25 | 1 | 10 | 8.62 | 52.35 | 200 | 70.26 |
40 | 75 | 1 | 14 | 8.70 | 55.02 | 110 | 2.45 |
41 | 75 | 5 | 6 | 8.93 | 55.39 | To be predicted | To be predicted |
42 | 25 | 4 | 14 | 9.27 | 55.81 | ||
43 | 25 | 5 | 12 | 8.83 | 56.13 | ||
44 | 50 | 1 | 10 | 9.18 | 52.78 | ||
45 | 25 | 4 | 12 | 8.72 | 54.51 | ||
46 | 25 | 3 | 10 | 9.26 | 56.66 | ||
47 | 50 | 1 | 12 | 9.23 | 55.51 | ||
48 | 25 | 2 | 12 | 8.73 | 51.44 | ||
49 | 25 | 1 | 14 | 9.03 | 56.44 | ||
50 | 50 | 2 | 6 | 9.17 | 55.12 |
Variables | Minimum | Maximum | Standard Deviation | Dispersion Coefficient | Coefficient of Skewness | Coefficient of Kurtosis | |
---|---|---|---|---|---|---|---|
Input layer | c (%) | 25 | 75 | 20.530 | 0.416 | 0.046 | −1.516 |
c (%) | 1 | 5 | 1.382 | 0.481 | 0.111 | −1.164 | |
c (%) | 6 | 14 | 2.810 | 0.282 | 0.153 | −1.253 | |
Permeability coefficient (before conditioning) (m/s) | 8.59 | 9.27 | 0.190 | 0.021 | −0.302 | −0.933 | |
Resistivity of sand (Ω·m) | 51.42 | 56.67 | 1.479 | 0.027 | −0.327 | −0.833 | |
Output layer | Slump value (mm) | 33 | 205 | 50.752 | 0.362 | −0.771 | −0.606 |
Permeability coefficient (after conditioning) (m/s) | 0.02 | 73.53 | 22.260 | 1.049 | 0.996 | −0.233 |
The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. |
Nong, X.; Bai, W.; Chen, J.; Zhang, L. Factorial Experiments of Soil Conditioning for Earth Pressure Balance Shield Tunnelling in Water-Rich Gravel Sand and Conditioning Effects’ Prediction Based on Particle Swarm Optimization–Relevance Vector Machine Algorithm. Buildings 2024 , 14 , 2800. https://doi.org/10.3390/buildings14092800
Nong X, Bai W, Chen J, Zhang L. Factorial Experiments of Soil Conditioning for Earth Pressure Balance Shield Tunnelling in Water-Rich Gravel Sand and Conditioning Effects’ Prediction Based on Particle Swarm Optimization–Relevance Vector Machine Algorithm. Buildings . 2024; 14(9):2800. https://doi.org/10.3390/buildings14092800
Nong, Xingzhong, Wenfeng Bai, Jiandang Chen, and Lihui Zhang. 2024. "Factorial Experiments of Soil Conditioning for Earth Pressure Balance Shield Tunnelling in Water-Rich Gravel Sand and Conditioning Effects’ Prediction Based on Particle Swarm Optimization–Relevance Vector Machine Algorithm" Buildings 14, no. 9: 2800. https://doi.org/10.3390/buildings14092800
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The roll-back of ballot measure 110 went into effect sept. 1.
Portland Police Central Bike Squad officer Donny Mathew cuffs a man arrested while in downtown Portland, Ore., Nov. 15, 2023.
Kristyna Wentz-Graff / OPB
Oregon has ended its experiment with drug decriminalization. Starting Sept. 1, possession of small amounts of illicit substances are once again considered a misdemeanor crime. Earlier this year, state lawmakers rolled back key provisions of Ballot Measure 110, the voter-passed initiative that decriminalized drugs nearly four years ago.
As the new law goes into effect, here’s what Oregonians need to know.
In 2020, Oregon voters approved Ballot Measure 110, which decriminalized possession of small amounts of drugs, like fentanyl and methamphetamine, in the state. Under the 110 system, drug users no longer received criminal penalties, but were instead served with a $100 ticket, which could be voided if the recipient got a needs assessment.
The idea behind the measure was to redirect people with substance use disorder away from a punishment-focused criminal justice system and instead direct them toward rehabilitation and treatment. But in the four years since it passed, the measure was widely considered a failure, leading to more open drug use and blamed for an increase in overdoses. An investigation by OPB and ProPublica found that it was due in part to state leaders who failed to make the measure work.
While some parts of Measure 110 are still in effect, lawmakers made significant changes. Enter House Bill 4002, which Gov. Tina Kotek signed into law April 1 . Possession under the new law is once again a misdemeanor crime, but the statute also sought to deliver on the promise of treatment outlined in Measure 110. The bill allocated millions of dollars for counties to establish so-called “deflection programs” to do just that.
Related: Multnomah County hits pause on deflection center opening
Deflection is a collaborative effort between law enforcement agencies and behavioral health entities to deflect people using drugs into treatment, and out of the criminal justice system. But how it works will depend on each county’s approach .
For example: In Baker County, law enforcement officers will provide “instructions, rights, and options” to people who possess drugs, but it will largely be on the individual to pursue deflection, according to the application submitted to the state.
Meanwhile, in Deschutes County, once a person is referred to the deflection program, staff will meet them where they’re at, according to the county’s application. When the staff member arrives, officers will release the person from custody and immediately conduct an initial screening.
Twenty-eight of Oregon’s 36 counties have applied for funding from the state to stand up their deflection programs. Of those participating, half said their programs would be ready Sept. 1, while others will take months to get their programs up and running.
A majority of those counties will only allow people charged with misdemeanor drug possession to enter their deflection program. While some counties will consider other low-level, public disorder crimes that can be associated with addiction, in their eligibility criteria, most will not.
For months, Multnomah County officials have been trying to open a deflection center in inner Southeast Portland, where law enforcement could drop off people who need assessments and direct them to treatment and services. But weeks before it was supposed to open, county officials announced that the center would be delayed until October .
The county was also served with a lawsuit Aug. 26 from a nearby preschool, saying officials violated public meeting laws in planning of the center.
A map of Multnomah County's planned deflection center in Southeast Portland. The facility will be operated by Baltimore nonprofit Tuerk House, which provides alcohol and drug treatment.
Michelle Wiley / Courtesy of Multnomah County
Until it’s ready, Multnomah County officials said they’ll do mobile outreach, deploying “behavioral health providers and professional peer specialists to respond to law enforcement in the field. They will conduct referrals, arrange and connect the eligible person to services,” according to a press release.
In Portland, police will provide evaluations for people they encounter. If they’re deemed eligible for deflection, the officer will call deflection dispatch, which will then contact the Peer Deflection Team. Officers will wait up to 30 minutes for that team to arrive and offer services, with the person arrested and held in handcuffs. If the deflection team doesn’t get there in time, police will document the wait time and take the person to jail.
Related: Oregon’s drug decriminalization aimed to make police a gateway to rehab, not jail. State leaders failed to make it work
Yes. Deflection programs are voluntary, not compulsory. In some places, that will likely mean a person with drugs is taken to jail.
But HB 4002 does lay out other options. If an individual refuses to participate in deflection, prosecutors could pursue conditional discharge, in which a person’s criminal charges get dismissed if they complete treatment, probation or even jail time.
That depends. While the aim of recriminalization, much like Measure 110, is to get people connected with drug treatment and services, there are ongoing capacity issues across the state. A recent study for the Oregon Health Authority found that the state needs to invest an additional $850 million over five years for behavioral health beds to meet projected needs.
In some places, while there may be services available, they might not meet the needs of everyone seeking care. In Washington County, behavioral health officials said that they have services during normal business hours — Monday through Friday, from 9 a.m.-5 p.m. — but outside of that window, options are limited.
“Currently in Washington County, there are no sobering resources. There is very limited residential treatment, there is no publicly funded withdrawal management,” said Nick Ocón, division manager with Washington County Behavioral Health.
Related: Oregon governor signs bill criminalizing drug possession
While the county, and others, are working to bring other services online, it may take time to get people the care they need.
Editor’s note: OPB would love to hear from you about how the recriminalization of small amounts of drug possession impacts you and your communities. Fill out the form below and provide insights on how OPB could cover stories around this issue in the future.
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It remains unclear whether microbial carbon limitation exists in the rhizosphere, a microbial hotspot characterized by intensive labile carbon input. Here, we collected rhizosphere soils attached to absorptive and transport roots and bulk soils in three alpine coniferous forests and evaluated the limiting resources of microbes based on the responses of microbial growth ( 18 O incorporation into DNA) and respiration to full-factorial amendments of carbon, nitrogen, and phosphorus. The results showed that adding carbon enhanced microbial growth and respiration rates in the rhizosphere soils by 1.2- and 10.3-fold, respectively, indicating the existence of carbon limitation for both anabolic and catabolic processes. In contrast, the promoting effects of nutrient addition were weak or manifested only after the alleviation of carbon limitation, suggesting that nutrients were co-limiting or secondarily limiting resources. Moreover, the category and extent of microbial resource limitations were comparable between the rhizosphere of absorptive and transport roots, and between the rhizosphere and bulk soils. Overall, our findings offer direct evidence for the presence of microbial carbon limitation in the rhizosphere.
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The datasets analyzed in the current study are available from the corresponding author on reasonable request.
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This study was supported jointly by the National Natural Science Foundation of China (U23A2051, 32201531, 32301446 and 32171757), the Chinese Academy of Sciences (CAS) Interdisciplinary Innovation Team (xbzg-zysys-202112), the Science and technology program of Tibet Autonomous Region (XZ202301YD0028C and XZ202301ZR0047G), and Sichuan Science and Technology Program (2023NSFSC0012 and 2023NSFSC1192). The authors highly appreciate the constructive comments from Editor-in-Chief Paolo Nannipieri and two anonymous reviewers, which have greatly improved the quality of this paper.
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CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province & China-Croatia “Belt and Road” Joint Laboratory on Biodiversity and Ecosystem Services, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610213, China
Jipeng Wang, Min Li, Qitong Wang, Dungang Wang, Peipei Zhang, Na Li & Huajun Yin
School of Ecology and Environment, Northwestern Polytechnical University, Xi’an, 710072, China
Ziliang Zhang
College of Ecology and Environment, Chengdu University of Technology, Chengdu, 610059, China
Yiqiu Zhong
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Correspondence to Huajun Yin .
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Wang, J., Li, M., Wang, Q. et al. Full-factorial resource amendment experiments reveal carbon limitation of rhizosphere microbes in alpine coniferous forests. Biol Fertil Soils (2024). https://doi.org/10.1007/s00374-024-01860-7
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Received : 12 May 2024
Revised : 20 August 2024
Accepted : 22 August 2024
Published : 05 September 2024
DOI : https://doi.org/10.1007/s00374-024-01860-7
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Factorial experiment
14.2: Design of experiments via factorial designs
In many factorial designs, one of the independent variables is a non-manipulated independent variable. The researcher measures it but does not manipulate it. The study by Schnall and colleagues is a good example. One independent variable was disgust, which the researchers manipulated by testing participants in a clean room or a messy room.
A full factorial design (also known as complete factorial design) is the most complete of the design options, meaning that each factor and level are combined to test every possible combination condition. Let us expand upon the theoretical ERAS factorial experiment as an illustrative example. We designed our own ERAS protocol for Whipple procedures, and our objective is to test which components ...
3.1: Factorial Designs
Coding Systems for the Factor Levels in the Factorial Design of Experiment. As the factorial design is primarily used for screening variables, only two levels are enough. Often, coding the levels as (1) low/high, (2) -/+ or (3) -1/+1 is more convenient and meaningful than the actual level of the factors, especially for the designs and analyses ...
5.2.6. Main Effects and Interactions. In factorial designs, there are two kinds of results that are of interest: main effects and interactions. A main effect is the statistical relationship between one independent variable and a dependent variable-averaging across the levels of the other independent variable (s).
A factorial design study uses more than one independent variable or factor. This design allows researchers to look at how multiple factors affect a dependent variable, both independently and together. Factorial design studies are titled by the number of levels of the factors. For example, a study with two factors that each have two levels is ...
Experiments of factorial design offer a highly efficient method to evaluate multiple component interventions. The main effect of multiple components can be measured with the same number of participants as a classic two-arm randomized controlled trial (RCT) while maintaining adequate statistical power. In addition, interactions between components can be estimated.
How a Factorial Design Works. Let's take a closer look at how a factorial design might work in a psychology experiment: The independent variable is the variable of interest that the experimenter will manipulate.; The dependent variable is the variable that the researcher then measures.; By doing this, psychologists can see if changing the independent variable results in some type of change ...
Topic 9. Factorial Experiments [ST&D Chapter 15]
Figure 9.1 Factorial Design Table Representing a 2 × 2 Factorial Design. In principle, factorial designs can include any number of independent variables with any number of levels. For example, an experiment could include the type of psychotherapy (cognitive vs. behavioral), the length of the psychotherapy (2 weeks vs. 2 months), and the sex of ...
A Complete Guide: The 2x2 Factorial Design
Factorial Experiment
For analysis of. 2n. factorial experiment, the analysis of variance involves the partitioning of treatment sum of squares so as to obtain sum of squares due to main and interaction effects of factors. These sum of squares are mutually orthogonal, so Treatment SS = Total of SS due to main and interaction effects.
ORIAL DESIGNS4.1 Two Factor Factorial DesignsA two-factor factorial design is an experimental design in which data is collected for all possible combination. sible factor combinations then the de. ign is abalanced two-factor factorial design.A balanced a b factorial design is a factorial design for which there are a levels of factor A, b levels ...
Answer: We learn the population means by estimating the common variance 2 in two di erent ways. These two estimators are formed by. measuring variability of the observations within each sample. measuring variability of the sample means across the samples. Idea: These two estimates tend to be similar when H0 is true.
Factor 1: three pulp preparation methods Factor 2: four cooking temperatures. Objective: study the effect on the tensile strength of the paper. Three replicates of a 4 ‚ 3 experiment A batch of pulp is produced by one of the three methods; then it is divided into 4 samples. Each sample is cooked at one temperature.
Formally, main effects are the mean differences for a single Independent variable. There is always one main effect for each IV. A 2x2 design has 2 IVs, so there are two main effects. In our example, there is one main effect for distraction, and one main effect for reward. We will often ask if the main effect of some IV is significant.
A mean square is an estimate of population variance. It is computed by dividing a sum of squares (SS) by its corresponding degrees of freedom (df), as shown below: MS = SS / df. To conduct analysis of variance with a two-factor, full factorial experiment, we are interested in four mean squares: Factor A mean square.
In many factorial designs, one of the independent variables is a non-manipulated independent variable. The researcher measures it but does not manipulate it. The study by Schnall and colleagues is a good example. One independent variable was disgust, which the researchers manipulated by testing participants in a clean room or a messy room.
Experimental Design: Types, Examples & Methods
Together, these suggest the QALY may be a flawed measure of the value of EOL care. To test these arguments, we administered a stated preference survey in a UK-representative public sample. ... Factorial Survey Experiments. 2015. View more. Open in viewer. Go to. Go to. Show all references. Request permissions Show all. Collapse. Expand Table.
The high permeability of gravel sand increases the risk of water spewing from the screw conveyor during earth pressure balance (EPB) shield tunnelling. The effectiveness of soil conditioning is a key factor affecting EPB shield tunnelling and construction safety. In this paper, using polymer, a foaming agent, and bentonite slurry as conditioning additives, the permeability coefficient tests of ...
On Sunday, Measure 110, Oregon's 3 1/2-year experiment will come to an end, and possession of small amounts of drugs will once again be considered a misdemeanor crime. Fed-up residents say it ...
The measure required officers to hand out $100 citations instead of jail time, and that citation could be waived if the person called a state-funded hotline and enrolled in an assessment for ...
Oregon has ended its experiment with drug decriminalization. Starting Sept. 1, possession of small amounts of illicit substances are once again considered a misdemeanor crime.
We conducted a full-factorial resource addition experiment to identify the limiting resources of microbial growth and respiration according to Demoling et al ... A repeated measures ANOVA, with soil compartment as the within-subjects factor and site as the between-subjects factor, was used to detect the differences between soil compartments and ...